docs: Document the [telemetry] trace toggles as 0 or 1

The configuration reference typed the five trace_* switches as bool with
default true. An xrpld config section carries integers, and these keys are
read with an integer cast, so a literal "true" fails to convert rather
than enabling the switch.

Type them as 0 or 1 with default 1, matching the other integer-valued
keys in the same table.

.clang-tidy

@@ -1,171 +1,92 @@
 ---
 Checks: "-*,
-  bugprone-argument-comment,
-  bugprone-assert-side-effect,
-  bugprone-bad-signal-to-kill-thread,
-  bugprone-bool-pointer-implicit-conversion,
-  bugprone-capturing-this-in-member-variable,
-  bugprone-casting-through-void,
-  bugprone-chained-comparison,
-  bugprone-compare-pointer-to-member-virtual-function,
-  bugprone-copy-constructor-init,
-  bugprone-crtp-constructor-accessibility,
-  bugprone-dangling-handle,
-  bugprone-dynamic-static-initializers,
-  bugprone-empty-catch,
-  bugprone-fold-init-type,
-  bugprone-forward-declaration-namespace,
-  bugprone-inaccurate-erase,
-  bugprone-inc-dec-in-conditions,
-  bugprone-incorrect-enable-if,
-  bugprone-incorrect-roundings,
-  bugprone-infinite-loop,
-  bugprone-integer-division,
-  bugprone-lambda-function-name,
-  bugprone-macro-parentheses,
-  bugprone-macro-repeated-side-effects,
-  bugprone-misleading-setter-of-reference,
-  bugprone-misplaced-operator-in-strlen-in-alloc,
-  bugprone-misplaced-pointer-arithmetic-in-alloc,
-  bugprone-misplaced-widening-cast,
-  bugprone-move-forwarding-reference,
-  bugprone-multi-level-implicit-pointer-conversion,
-  bugprone-multiple-new-in-one-expression,
-  bugprone-multiple-statement-macro,
-  bugprone-no-escape,
-  bugprone-non-zero-enum-to-bool-conversion,
-  bugprone-optional-value-conversion,
-  bugprone-parent-virtual-call,
-  bugprone-pointer-arithmetic-on-polymorphic-object,
-  bugprone-posix-return,
-  bugprone-redundant-branch-condition,
-  bugprone-reserved-identifier,
-  bugprone-return-const-ref-from-parameter,
-  bugprone-shared-ptr-array-mismatch,
-  bugprone-signal-handler,
-  bugprone-signed-char-misuse,
-  bugprone-sizeof-container,
-  bugprone-sizeof-expression,
-  bugprone-spuriously-wake-up-functions,
-  bugprone-standalone-empty,
-  bugprone-string-constructor,
-  bugprone-string-integer-assignment,
-  bugprone-string-literal-with-embedded-nul,
-  bugprone-stringview-nullptr,
-  bugprone-suspicious-enum-usage,
-  bugprone-suspicious-include,
-  bugprone-suspicious-memory-comparison,
-  bugprone-suspicious-memset-usage,
-  bugprone-suspicious-missing-comma,
-  bugprone-suspicious-realloc-usage,
-  bugprone-suspicious-semicolon,
-  bugprone-suspicious-string-compare,
-  bugprone-suspicious-stringview-data-usage,
-  bugprone-swapped-arguments,
-  bugprone-switch-missing-default-case,
-  bugprone-terminating-continue,
-  bugprone-throw-keyword-missing,
-  bugprone-too-small-loop-variable,
-  bugprone-unchecked-optional-access,
-  bugprone-undefined-memory-manipulation,
-  bugprone-undelegated-constructor,
-  bugprone-unhandled-exception-at-new,
-  bugprone-unhandled-self-assignment,
-  bugprone-unique-ptr-array-mismatch,
-  bugprone-unsafe-functions,
-  bugprone-unused-local-non-trivial-variable,
-  bugprone-unused-raii,
-  bugprone-unused-return-value,
-  bugprone-use-after-move,
-  bugprone-virtual-near-miss,
-  cppcoreguidelines-init-variables,
-  cppcoreguidelines-misleading-capture-default-by-value,
-  cppcoreguidelines-no-suspend-with-lock,
-  cppcoreguidelines-pro-type-member-init,
-  cppcoreguidelines-pro-type-static-cast-downcast,
-  cppcoreguidelines-rvalue-reference-param-not-moved,
-  cppcoreguidelines-use-default-member-init,
-  cppcoreguidelines-use-enum-class,
-  cppcoreguidelines-virtual-class-destructor,
-  hicpp-ignored-remove-result,
+  bugprone-*,
+  -bugprone-easily-swappable-parameters,
+  -bugprone-exception-escape,
+  -bugprone-implicit-widening-of-multiplication-result,
+  -bugprone-narrowing-conversions,
+  -bugprone-throwing-static-initialization,
+
+  cppcoreguidelines-*,
+  -cppcoreguidelines-avoid-c-arrays,
+  -cppcoreguidelines-avoid-const-or-ref-data-members,
+  -cppcoreguidelines-avoid-do-while,
+  -cppcoreguidelines-avoid-magic-numbers,
+  -cppcoreguidelines-avoid-non-const-global-variables,
+  -cppcoreguidelines-c-copy-assignment-signature,
+  -cppcoreguidelines-interfaces-global-init,
+  -cppcoreguidelines-macro-usage,
+  -cppcoreguidelines-missing-std-forward,
+  -cppcoreguidelines-narrowing-conversions,
+  -cppcoreguidelines-noexcept-move-operations,
+  -cppcoreguidelines-non-private-member-variables-in-classes,
+  -cppcoreguidelines-owning-memory,
+  -cppcoreguidelines-pro-bounds-array-to-pointer-decay,
+  -cppcoreguidelines-pro-bounds-avoid-unchecked-container-access,
+  -cppcoreguidelines-pro-bounds-constant-array-index,
+  -cppcoreguidelines-pro-bounds-pointer-arithmetic,
+  -cppcoreguidelines-pro-type-reinterpret-cast,
+  -cppcoreguidelines-pro-type-union-access,
+  -cppcoreguidelines-special-member-functions,
+
   llvm-namespace-comment,
-  misc-const-correctness,
-  misc-definitions-in-headers,
-  misc-header-include-cycle,
-  misc-include-cleaner,
-  misc-misplaced-const,
-  misc-redundant-expression,
-  misc-static-assert,
-  misc-throw-by-value-catch-by-reference,
-  misc-unused-alias-decls,
-  misc-unused-using-decls,
-  modernize-concat-nested-namespaces,
-  modernize-deprecated-headers,
-  modernize-make-shared,
-  modernize-make-unique,
-  modernize-pass-by-value,
-  modernize-type-traits,
-  modernize-use-designated-initializers,
-  modernize-use-emplace,
-  modernize-use-equals-default,
-  modernize-use-equals-delete,
-  modernize-use-nodiscard,
-  modernize-use-override,
-  modernize-use-ranges,
-  modernize-use-scoped-lock,
-  modernize-use-starts-ends-with,
-  modernize-use-std-numbers,
-  modernize-use-using,
-  performance-faster-string-find,
-  performance-for-range-copy,
-  performance-implicit-conversion-in-loop,
-  performance-inefficient-vector-operation,
-  performance-move-const-arg,
-  performance-move-constructor-init,
-  performance-no-automatic-move,
-  performance-trivially-destructible,
-  readability-ambiguous-smartptr-reset-call,
-  readability-avoid-nested-conditional-operator,
-  readability-avoid-return-with-void-value,
-  readability-braces-around-statements,
-  readability-const-return-type,
-  readability-container-contains,
-  readability-container-size-empty,
-  readability-convert-member-functions-to-static,
-  readability-duplicate-include,
-  readability-else-after-return,
-  readability-enum-initial-value,
-  readability-identifier-naming,
-  readability-implicit-bool-conversion,
-  readability-make-member-function-const,
-  readability-math-missing-parentheses,
-  readability-misleading-indentation,
-  readability-non-const-parameter,
-  readability-redundant-casting,
-  readability-redundant-declaration,
-  readability-redundant-inline-specifier,
-  readability-redundant-member-init,
-  readability-redundant-string-init,
-  readability-reference-to-constructed-temporary,
-  readability-simplify-boolean-expr,
-  readability-static-definition-in-anonymous-namespace,
-  readability-suspicious-call-argument,
-  readability-use-std-min-max
+
+  misc-*,
+  -misc-multiple-inheritance,
+  -misc-no-recursion,
+  -misc-non-private-member-variables-in-classes,
+  -misc-override-with-different-visibility,
+  -misc-unused-parameters,
+  -misc-use-anonymous-namespace,
+  -misc-use-internal-linkage,
+
+  modernize-*,
+  -modernize-avoid-c-arrays,
+  -modernize-avoid-c-style-cast,
+  -modernize-return-braced-init-list,
+  -modernize-use-integer-sign-comparison,
+  -modernize-use-trailing-return-type,
+
+  performance-*,
+  -performance-avoid-endl,
+  -performance-enum-size,
+  -performance-noexcept-move-constructor,
+  -performance-unnecessary-copy-initialization,
+  -performance-unnecessary-value-param,
+
+  readability-*,
+  -readability-avoid-const-params-in-decls,
+  -readability-container-data-pointer,
+  -readability-function-cognitive-complexity,
+  -readability-identifier-length,
+  -readability-inconsistent-declaration-parameter-name,
+  -readability-isolate-declaration,
+  -readability-magic-numbers,
+  -readability-named-parameter,
+  -readability-qualified-auto,
+  -readability-redundant-access-specifiers,
+  -readability-static-accessed-through-instance,
+  -readability-uppercase-literal-suffix
   "
 # ---
-# bugprone-narrowing-conversions,                      # this will break a lot of code but we should enable it in the future because it can eliminate a lot of bugs
-# readability-inconsistent-declaration-parameter-name, # in this codebase this check will break a lot of arg names
-# readability-static-accessed-through-instance,        # this check is probably unnecessary. it makes the code less readable
+# bugprone-narrowing-conversions,                      # This will break a lot of code but we should enable it in the future because it can eliminate a lot of bugs
+# misc-override-with-different-visibility,             # Will be addressed in a future PR, but for now it generates too many warnings
+# readability-inconsistent-declaration-parameter-name, # In this codebase this check will break a lot of arg names
+# readability-static-accessed-through-instance,        # this check is probably unnecessary. It makes the code less readable
 # ---
 
+FormatStyle: file
+
 CheckOptions:
   bugprone-unsafe-functions.ReportMoreUnsafeFunctions: true
   bugprone-unused-return-value.CheckedReturnTypes: ::std::error_code;::std::error_condition;::std::errc
 
-  misc-include-cleaner.IgnoreHeaders: ".*/(detail|impl)/.*;.*fwd\\.h(pp)?;time.h;stdlib.h;sqlite3.h;netinet/in\\.h;sys/resource\\.h;sys/sysinfo\\.h;linux/sysinfo\\.h;__chrono/.*;bits/.*;_abort\\.h;boost/uuid/uuid_hash.hpp;boost/beast/core/flat_buffer\\.hpp;boost/beast/http/field\\.hpp;boost/beast/http/dynamic_body\\.hpp;boost/beast/http/message\\.hpp;boost/beast/http/read\\.hpp;boost/beast/http/write\\.hpp;openssl/obj_mac\\.h"
+  misc-include-cleaner.IgnoreHeaders: ".*/(detail|impl)/.*;.*fwd\\.h(pp)?;time.h;stdlib.h;sqlite3.h;netinet/in\\.h;sys/resource\\.h;sys/sysinfo\\.h;linux/sysinfo\\.h;__chrono/.*;bits/.*;_abort\\.h;boost/.*;openssl/obj_mac\\.h"
 
   readability-braces-around-statements.ShortStatementLines: 2
   readability-identifier-naming.MacroDefinitionCase: UPPER_CASE
+  readability-identifier-naming.NamespaceCase: lower_case
+  readability-identifier-naming.InlineNamespaceCase: lower_case
   readability-identifier-naming.ClassCase: CamelCase
   readability-identifier-naming.StructCase: CamelCase
   readability-identifier-naming.UnionCase: CamelCase

.codecov.yml

@@ -1,10 +1,32 @@
 codecov:
   require_ci_to_pass: true
+  # The C++ and Rust uploads land minutes apart; without this gate Codecov
+  # publishes a near-zero total from whichever one arrives first.
+  notify:
+    after_n_builds: 2
+    wait_for_ci: true
 
 comment:
   behavior: default
   layout: reach,diff,flags,tree,reach
-  show_carryforward_flags: false
+  show_carryforward_flags: true
+  after_n_builds: 2
+
+# C++ and Rust coverage upload from independent workflows under the `cpp` and
+# `rust` flags; carryforward keeps one language's total when only the other reran.
+flag_management:
+  default_rules:
+    carryforward: true
+  individual_flags:
+    - name: cpp
+      carryforward: true
+      paths:
+        - include/
+        - src/
+    - name: rust
+      carryforward: true
+      paths:
+        - crates/
 
 coverage:
   range: "70..85"

.cspell.config.yaml

@@ -7,6 +7,7 @@ ignorePaths:
   - cmake/**
   - LICENSE.md
   - .clang-tidy
+  - nix/check-tools/*.txt # generated, and full of Nix store hashes
 language: en
 allowCompoundWords: true # TODO (#6334)
 ignoreRandomStrings: true
@@ -30,15 +31,15 @@ ignoreRegExpList:
   - ABCDEFGHIJKLMNOPQRSTUVWXYZ
   - ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz
 overrides:
-  - filename: "**/*_test.cpp" # all test files
+  - filename:
+      - "**/*_test.cpp" # legacy boost.test files
+      - "src/tests/**/*.cpp" # gtest test files
     ignoreRegExpList:
       - /"[^"]*"/g # double-quoted strings
       - /'[^']*'/g # single-quoted strings
       - /`[^`]*`/g # backtick strings
 suggestWords:
-  - xprl->xrpl
-  - xprld->xrpld # cspell: disable-line not sure what this problem is....
-  - unsynched->unsynced # cspell: disable-line not sure what this problem is....
+  - unsynched->unsynced
   - synched->synced
   - synch->sync
 words:
@@ -50,6 +51,7 @@ words:
   - AMMXRP
   - amt
   - amts
+  - archs
   - asnode
   - asynchrony
   - attestation
@@ -59,12 +61,16 @@ words:
   - autobridging
   - bimap
   - bindir
+  - blindings
   - bookdir
   - Bougalis
   - Britto
   - Btrfs
   - Buildx
   - canonicality
+  - CGNAT
+  - canonicalised
+  - cctools
   - changespq
   - checkme
   - choco
@@ -72,6 +78,7 @@ words:
   - citardauq
   - clawback
   - clawbacks
+  - clippy
   - cmaketoolchain
   - coeffs
   - coldwallet
@@ -83,6 +90,7 @@ words:
   - coro
   - coros
   - cowid
+  - cpack
   - cryptocondition
   - cryptoconditional
   - cryptoconditions
@@ -93,6 +101,7 @@ words:
   - daria
   - dcmake
   - dearmor
+  - decryptor
   - dedented
   - deleteme
   - demultiplexer
@@ -103,10 +112,13 @@ words:
   - disablerepo
   - distro
   - doxyfile
+  - dsymutil
   - dxrpl
+  - elgamal
   - enabled
   - enablerepo
   - endmacro
+  - envrc
   - exceptioned
   - EXPECT_STREQ
   - Falco
@@ -116,6 +128,9 @@ words:
   - fmtdur
   - fsanitize
   - funclets
+  - Gamal
+  - gantt
+  - Gantt
   - gcov
   - gcovr
   - ghead
@@ -123,6 +138,7 @@ words:
   - godexsoft
   - gpgcheck
   - gpgkey
+  - Hinnant
   - hotwallet
   - hwaddress
   - hwrap
@@ -134,6 +150,7 @@ words:
   - iou
   - ious
   - isrdc
+  - isystem
   - itype
   - jemalloc
   - jlog
@@ -155,18 +172,18 @@ words:
   - llection
   - LOCALGOOD
   - logwstream
+  - Lombrozo
+  - lresolv
   - lseq
   - lsmf
   - ltype
   - mathbunnyru
   - mcmodel
   - MEMORYSTATUSEX
-  - MPTAMM
-  - MPTDEX
   - Merkle
-  - Metafuncton
   - misprediction
   - missingok
+  - MPTAMM
   - mptbalance
   - MPTDEX
   - mptflags
@@ -192,6 +209,7 @@ words:
   - nftokens
   - nftpage
   - nikb
+  - Nikolaos
   - nixfmt
   - nixos
   - nixpkgs
@@ -200,6 +218,7 @@ words:
   - nonxrp
   - noreplace
   - noripple
+  - nostd
   - nostdinc
   - notifempty
   - nudb
@@ -208,10 +227,14 @@ words:
   - Nyffenegger
   - onlatest
   - ostr
+  - otelc
+  - otool
+  - oxalica
   - pargs
   - partitioner
   - paychan
   - paychans
+  - Pedersen
   - permdex
   - perminute
   - permissioned
@@ -230,10 +253,20 @@ words:
   - pyenv
   - pyparsing
   - qalloc
+  - qbsprofile
   - queuable
   - Raphson
+  - rcflags
   - replayer
+  - repodata
+  - repomd
+  - rerandomize
+  - rerandomization
+  - rerandomized
+  - rerandomizes
   - rerere
+  - retargeted
+  - retargets
   - retriable
   - RIPD
   - ripdtop
@@ -246,9 +279,13 @@ words:
   - rocksdb
   - Rohrs
   - roundings
+  - rustc
+  - rustfmt
+  - rustup
   - sahyadri
   - Satoshi
   - scons
+  - Schnorr
   - secp
   - sendq
   - seqit
@@ -265,6 +302,9 @@ words:
   - sles
   - soci
   - socidb
+  - Sonatype
+  - sponsee
+  - sponsees
   - SRPMS
   - sslws
   - statsd
@@ -279,12 +319,17 @@ words:
   - stvar
   - stvector
   - stxchainattestations
+  - summands
   - superpeer
   - superpeers
+  - Swatinem
   - takergets
   - takerpays
   - ters
   - TMEndpointv2
+  - toolchain
+  - tparam
+  - traceql
   - trixie
   - tx
   - txid
@@ -292,9 +337,11 @@ words:
   - txjson
   - txn
   - txns
+  - txqueue
   - txs
   - ubsan
   - UBSAN
+  - ufdio
   - umant
   - unacquired
   - unambiguity
@@ -311,9 +358,11 @@ words:
   - unserviced
   - unshareable
   - unshares
+  - unsponsored
   - unsquelch
   - unsquelched
   - unsquelching
+  - unsuffixed
   - unvalidated
   - unveto
   - unvetoed
@@ -331,12 +380,16 @@ words:
   - wthread
   - xbridge
   - xchain
+  - xcrun
   - ximinez
   - XMACRO
+  - xored
   - xrpkuwait
   - xrpl
   - xrpld
   - xrplf
   - xxhash
   - xxhasher
-  - CGNAT
+  - xychart
+  - zpages
+  - zstdio

.envrc

@@ -0,0 +1,7 @@
+watch_file nix/*.nix
+
+# The dev shell derivation includes all of conan/ (see nix/devshell.nix), so any
+# change in there has to invalidate direnv's cached environment.
+watch_dir conan
+
+use flake

.gersemi/definitions.cmake

@@ -11,7 +11,7 @@ endfunction()
 function(create_symbolic_link target link)
 endfunction()
 
-function(xrpl_add_test name)
+function(xrpl_add_benchmark name)
 endfunction()
 
 macro(exclude_from_default target_)
@@ -51,6 +51,12 @@ endfunction()
 function(add_module parent name)
 endfunction()
 
+function(verify_target_headers target headers_dir)
+endfunction()
+
+function(_verify_add_headers target dir)
+endfunction()
+
 function(setup_protocol_autogen)
 endfunction()
 
@@ -99,3 +105,6 @@ function(verbose_find_path variable name)
         ${ARGN}
     )
 endfunction()
+
+function(patch_nix_binary target)
+endfunction()

.github/actions/build-deps/action.yml

@@ -35,9 +35,8 @@ runs:
         LOG_VERBOSITY: ${{ inputs.log_verbosity }}
         SANITIZERS: ${{ inputs.sanitizers }}
       run: |
-        echo 'Installing dependencies.'
         conan install \
-            --profile ci \
+            --profile:all ci \
             --build="${BUILD_OPTION}" \
             --options:host='&:tests=True' \
             --options:host='&:xrpld=True' \

.github/actions/generate-version/action.yml

@@ -1,44 +0,0 @@
-name: Generate build version number
-description: "Generate build version number."
-
-outputs:
-  version:
-    description: "The generated build version number."
-    value: ${{ steps.version.outputs.version }}
-
-runs:
-  using: composite
-  steps:
-    # When a tag is pushed, the version is used as-is.
-    - name: Generate version for tag event
-      if: ${{ startsWith(github.ref, 'refs/tags/') }}
-      shell: bash
-      env:
-        VERSION: ${{ github.ref_name }}
-      run: echo "VERSION=${VERSION}" >>"${GITHUB_ENV}"
-
-    # When a tag is not pushed, then the version (e.g. 1.2.3-b0) is extracted
-    # from the BuildInfo.cpp file and the shortened commit hash appended to it.
-    # We use a plus sign instead of a hyphen because Conan recipe versions do
-    # not support two hyphens.
-    - name: Generate version for non-tag event
-      if: ${{ !startsWith(github.ref, 'refs/tags/') }}
-      shell: bash
-      run: |
-        echo 'Extracting version from BuildInfo.cpp.'
-        VERSION="$(cat src/libxrpl/protocol/BuildInfo.cpp | grep "versionString =" | awk -F '"' '{print $2}')"
-        if [[ -z "${VERSION}" ]]; then
-            echo 'Unable to extract version from BuildInfo.cpp.'
-            exit 1
-        fi
-
-        echo 'Appending shortened commit hash to version.'
-        SHA='${{ github.sha }}'
-        VERSION="${VERSION}+${SHA:0:7}"
-
-        echo "VERSION=${VERSION}" >>"${GITHUB_ENV}"
-
-    - name: Output version
-      id: version
-      shell: bash
-      run: echo "version=${VERSION}" >>"${GITHUB_OUTPUT}"

.github/actions/release-info/action.yml

@@ -0,0 +1,90 @@
+name: Release info
+description: "Derive the version, release channel and package release number for this build."
+
+outputs:
+  version:
+    description: "The build version number."
+    value: ${{ steps.version.outputs.version }}
+  channel:
+    description: "The release channel this build belongs to."
+    value: ${{ steps.channel.outputs.channel }}
+  pkg_release:
+    description: "The package release number: 1 for a tag, the run number otherwise."
+    value: ${{ steps.pkg_release.outputs.pkg_release }}
+
+runs:
+  using: composite
+  steps:
+    # A tag names its own version. Anything else takes it from BuildInfo.cpp and
+    # appends the commit hash as build metadata, joined with a plus sign because a
+    # Conan version cannot contain two hyphens.
+    - name: Determine version
+      id: version
+      shell: bash
+      env:
+        IS_TAG: ${{ startsWith(github.ref, 'refs/tags/') }}
+        REF_NAME: ${{ github.ref_name }}
+        SHA: ${{ github.sha }}
+      run: |
+        if [[ "${IS_TAG}" == "true" ]]; then
+            version="${REF_NAME}"
+        else
+            version="$(awk -F'"' '/versionString =/ { print $2 }' src/libxrpl/protocol/BuildInfo.cpp)"
+            if [[ -z "${version}" ]]; then
+                echo "Unable to read versionString from BuildInfo.cpp." >&2
+                exit 1
+            fi
+            version="${version}+${SHA:0:7}"
+        fi
+
+        echo "version=${version}" | tee -a "${GITHUB_OUTPUT}"
+
+    # Only a tag says how mature a build is: a push is a develop build whatever
+    # its version, and a non-public codebase keeps its packages to itself.
+    - name: Determine release channel
+      id: channel
+      shell: bash
+      env:
+        IS_TAG: ${{ startsWith(github.ref, 'refs/tags/') }}
+        REF_NAME: ${{ github.ref_name }}
+        VISIBILITY: ${{ github.event.repository.visibility }}
+      run: |
+        pre_release=""
+        if [[ "${REF_NAME}" == *-* ]]; then
+            pre_release="${REF_NAME#*-}"
+        fi
+
+        if [[ "${VISIBILITY}" != "public" ]]; then
+            channel=private
+        elif [[ "${IS_TAG}" != "true" ]]; then
+            channel=develop
+        elif [[ -z "${pre_release}" ]]; then
+            channel=stable
+        elif [[ "${pre_release}" =~ ^rc[0-9]+(\+.*)?$ ]]; then
+            channel=unstable
+        elif [[ "${pre_release}" =~ ^b(0|[1-9][0-9]*)(\+.*)?$ ]]; then
+            channel=experimental
+        else
+            echo "Unsupported pre-release in tag '${REF_NAME}'. Use bN or rcN." >&2
+            exit 1
+        fi
+
+        echo "channel=${channel}" | tee -a "${GITHUB_OUTPUT}"
+
+    # A tag is packaged once, so its release number is fixed at 1. Develop builds
+    # repeat the same version, so the run number is what makes each push an
+    # upgrade rather than a reinstall.
+    - name: Determine package release
+      id: pkg_release
+      shell: bash
+      env:
+        IS_TAG: ${{ startsWith(github.ref, 'refs/tags/') }}
+        RUN_NUMBER: ${{ github.run_number }}
+      run: |
+        if [[ "${IS_TAG}" == "true" ]]; then
+            pkg_release=1
+        else
+            pkg_release="${RUN_NUMBER}"
+        fi
+
+        echo "pkg_release=${pkg_release}" | tee -a "${GITHUB_OUTPUT}"

.github/actions/set-compiler-env/action.yml

@@ -0,0 +1,34 @@
+name: Set compiler environment
+description: "Set CC and CXX environment variables for the given compiler."
+
+inputs:
+  compiler:
+    description: 'The compiler to use ("gcc" or "clang").'
+    required: true
+
+runs:
+  using: composite
+
+  steps:
+    - name: Set CC and CXX for gcc
+      if: ${{ inputs.compiler == 'gcc' }}
+      shell: bash
+      run: |
+        echo "CC=gcc" >>"${GITHUB_ENV}"
+        echo "CXX=g++" >>"${GITHUB_ENV}"
+
+    - name: Set CC and CXX for clang
+      if: ${{ inputs.compiler == 'clang' }}
+      shell: bash
+      run: |
+        echo "CC=clang" >>"${GITHUB_ENV}"
+        echo "CXX=clang++" >>"${GITHUB_ENV}"
+
+    - name: Fail on unknown compiler
+      if: ${{ inputs.compiler != 'gcc' && inputs.compiler != 'clang' }}
+      shell: bash
+      env:
+        COMPILER: ${{ inputs.compiler }}
+      run: |
+        echo "Unknown compiler: $COMPILER" >&2
+        exit 1

.github/actions/setup-conan/action.yml

@@ -9,38 +9,41 @@ inputs:
   remote_url:
     description: "The URL of the Conan endpoint to use."
     required: false
-    default: https://conan.ripplex.io
+    default: https://conan.xrplf.org/repository/conan/
 
 runs:
   using: composite
 
   steps:
-    - name: Set up Conan configuration
+    - name: Apply custom configuration to global.conf
       shell: bash
       run: |
-        echo 'Installing configuration.'
         cat conan/global.conf ${{ runner.os == 'Linux' && '>>' || '>' }} $(conan config home)/global.conf
 
-        echo 'Conan configuration:'
-        conan config show '*'
-
-    - name: Set up Conan profile
+    - name: Show global configuration
+      shell: bash
+      run: |
+        conan config show '*'
+
+    - name: Install profiles
       shell: bash
       run: |
-        echo 'Installing profile.'
         conan config install conan/profiles/ -tf $(conan config home)/profiles/
 
-        echo 'Conan profile:'
+    - name: Show CI profile
+      shell: bash
+      run: |
         conan profile show --profile ci
 
-    - name: Set up Conan remote
+    - name: Add a remote
       shell: bash
       env:
         REMOTE_NAME: ${{ inputs.remote_name }}
         REMOTE_URL: ${{ inputs.remote_url }}
       run: |
-        echo "Adding Conan remote '${REMOTE_NAME}' at '${REMOTE_URL}'."
         conan remote add --index 0 --force "${REMOTE_NAME}" "${REMOTE_URL}"
 
-        echo 'Listing Conan remotes.'
+    - name: List remotes
+      shell: bash
+      run: |
         conan remote list

.github/actions/setup-nix-env/action.yml

@@ -0,0 +1,69 @@
+name: Setup Nix environment
+description: "Build the flake's CI environment and put its tools on PATH."
+
+# The environment from nix/ci-env.nix, the same one the Linux CI images bake in
+# (see nix/docker). Exported onto PATH rather than entered with `nix develop`:
+# the composite actions below run plain `bash` and would escape a dev shell.
+
+runs:
+  using: composite
+
+  steps:
+    - name: Build the CI environment
+      id: build
+      shell: bash
+      env:
+        # --out-link doubles as a GC root for the length of the job.
+        OUT_LINK: ${{ runner.temp }}/xrpld-ci-env
+      run: |
+        # --extra-experimental-features: flakes may not be on in the runner's nix.conf.
+        nix --extra-experimental-features "nix-command flakes" \
+            build .#default --out-link "${OUT_LINK}" --print-build-logs
+        echo "path=$(readlink -f "${OUT_LINK}")" >>"${GITHUB_OUTPUT}"
+
+    - name: Export the environment
+      shell: bash
+      env:
+        ENV_PATH: ${{ steps.build.outputs.path }}
+      run: |
+        echo "${ENV_PATH}/bin" >>"${GITHUB_PATH}"
+
+        # Already KEY=VALUE per line. See `darwinEnv` in nix/ci-env.nix.
+        ENV_FILE="${ENV_PATH}/share/xrpld-ci-env/env"
+        if [ -f "${ENV_FILE}" ]; then
+            cat "${ENV_FILE}" >>"${GITHUB_ENV}"
+        fi
+
+        # XrplSanity.cmake otherwise rejects a Nix compiler as one that leaked.
+        echo "XRPL_DEVSHELL=ci-env" >>"${GITHUB_ENV}"
+
+        # Unlike the Linux nix images, macOS needs no SSL_CERT_FILE: it has its
+        # own trust store, and pinning would break TLS to hosts relying on it.
+
+        # Workspace-local, so `cleanup-workspace` clears it, but not the
+        # `.conan2` prepare-runner hands the system toolchain: that Conan is a
+        # different version, and the two would migrate each other's cache.
+        echo "CONAN_HOME=${{ github.workspace }}/.conan2-nix" >>"${GITHUB_ENV}"
+
+    # Config, profiles and remote, exactly as the dev shell sets them up on
+    # entry; the `setup-conan` action is skipped for this toolchain.
+    - name: Setup Conan
+      shell: bash
+      run: ./conan/init.sh
+
+    # `Check tools` runs later but swallows failures; a bad export would just
+    # build with the system toolchain.
+    - name: Verify the toolchain resolves into the Nix store
+      shell: bash
+      run: |
+        for tool in clang clang++ cmake ninja conan; do
+            path="$(command -v "${tool}" || true)"
+            echo "${tool} -> ${path:-<not found>}"
+            case "${path}" in
+                /nix/store/*) ;;
+                *)
+                    echo "::error::${tool} does not resolve into the Nix store"
+                    exit 1
+                    ;;
+            esac
+        done

.github/dependabot.yml

@@ -1,7 +1,12 @@
 version: 2
 updates:
   - package-ecosystem: github-actions
-    directory: /
+    directories:
+      - /
+      - .github/actions/build-deps/
+      - .github/actions/release-info/
+      - .github/actions/set-compiler-env/
+      - .github/actions/setup-conan/
     schedule:
       interval: weekly
       day: monday
@@ -10,36 +15,23 @@ updates:
     commit-message:
       prefix: "ci: [DEPENDABOT] "
     target-branch: develop
+    groups:
+      github-actions:
+        patterns:
+          - "*"
 
-  - package-ecosystem: github-actions
-    directory: .github/actions/build-deps/
+  - package-ecosystem: cargo
+    directory: /crates
     schedule:
       interval: weekly
       day: monday
       time: "04:00"
       timezone: Etc/GMT
     commit-message:
-      prefix: "ci: [DEPENDABOT] "
-    target-branch: develop
-
-  - package-ecosystem: github-actions
-    directory: .github/actions/generate-version/
-    schedule:
-      interval: weekly
-      day: monday
-      time: "04:00"
-      timezone: Etc/GMT
-    commit-message:
-      prefix: "ci: [DEPENDABOT] "
-    target-branch: develop
-
-  - package-ecosystem: github-actions
-    directory: .github/actions/setup-conan/
-    schedule:
-      interval: weekly
-      day: monday
-      time: "04:00"
-      timezone: Etc/GMT
-    commit-message:
-      prefix: "ci: [DEPENDABOT] "
+      prefix: "chore: [DEPENDABOT] "
     target-branch: develop
+    open-pull-requests-limit: 10
+    groups:
+      rust-dependencies:
+        patterns:
+          - "*"

.github/pull_request_template.md

@@ -1,10 +1,10 @@
 <!--
-This PR template helps you to write a good pull request description.
+This PR template helps you write a good pull request description.
 Please feel free to include additional useful information even beyond what is requested below.
 
 If your branch is on a personal fork and has a name that allows it to
 run CI build/test jobs (e.g. "ci/foo"), remember to rename it BEFORE
-opening the PR.  This avoids unnecessary redundant test runs. Renaming
+opening the PR. This avoids redundant test runs. Renaming
 the branch after opening the PR will close the PR.
 https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-branches-in-your-repository/renaming-a-branch
 -->
@@ -15,7 +15,7 @@ https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-
 Please include a summary of the changes.
 This may be a direct input to the release notes.
 If too broad, please consider splitting into multiple PRs.
-If a relevant task or issue, please link it here.
+If there is a relevant task or issue, please link it here.
 -->
 
 ### Context of Change
@@ -65,5 +65,5 @@ This section may not be needed if your change includes thoroughly commented unit
 
 <!--
 ## Future Tasks
-For future tasks related to PR.
+For future tasks related to this PR.
 -->

.github/scripts/levelization/README.md

@@ -40,18 +40,18 @@ listed later.
 | 04           | xrpl/protocol                       |
 | 05           | xrpl/core xrpl/resource xrpl/server |
 | 06           | xrpl/ledger xrpl/nodestore xrpl/net |
-| 07           | xrpl/shamap                         |
+| 07           | xrpl/shamap xrpl/consensus          |
 
 ## xrpld Modules (Application Implementation)
 
-| Level / Tier | Module(s)                        |
-| ------------ | -------------------------------- |
-| 05           | xrpld/conditions xrpld/consensus |
-| 06           | xrpld/core xrpld/peerfinder      |
-| 07           | xrpld/shamap xrpld/overlay       |
-| 08           | xrpld/app                        |
-| 09           | xrpld/rpc                        |
-| 10           | xrpld/perflog                    |
+| Level / Tier | Module(s)                   |
+| ------------ | --------------------------- |
+| 05           | xrpld/conditions            |
+| 06           | xrpld/core xrpld/peerfinder |
+| 07           | xrpld/shamap xrpld/overlay  |
+| 08           | xrpld/app                   |
+| 09           | xrpld/rpc                   |
+| 10           | xrpld/perflog               |
 
 ## Test Modules
 

.github/scripts/levelization/results/loops.txt

@@ -1,15 +1,6 @@
-Loop: test.jtx test.toplevel
-  test.toplevel > test.jtx
-
-Loop: test.jtx test.unit_test
-  test.unit_test ~= test.jtx
-
 Loop: xrpld.app xrpld.overlay
   xrpld.app > xrpld.overlay
 
-Loop: xrpld.app xrpld.peerfinder
-  xrpld.peerfinder ~= xrpld.app
-
 Loop: xrpld.app xrpld.rpc
   xrpld.rpc > xrpld.app
 

.github/scripts/levelization/results/ordering.txt

@@ -1,6 +1,13 @@
+benchmarks.libxrpl > xrpl.basics
+benchmarks.libxrpl > xrpl.config
+benchmarks.libxrpl > xrpl.nodestore
 libxrpl.basics > xrpl.basics
 libxrpl.conditions > xrpl.basics
 libxrpl.conditions > xrpl.conditions
+libxrpl.config > xrpl.basics
+libxrpl.config > xrpl.config
+libxrpl.consensus > xrpl.basics
+libxrpl.consensus > xrpl.consensus
 libxrpl.core > xrpl.basics
 libxrpl.core > xrpl.core
 libxrpl.core > xrpl.json
@@ -16,13 +23,18 @@ libxrpl.ledger > xrpl.shamap
 libxrpl.net > xrpl.basics
 libxrpl.net > xrpl.net
 libxrpl.nodestore > xrpl.basics
+libxrpl.nodestore > xrpl.config
 libxrpl.nodestore > xrpl.json
 libxrpl.nodestore > xrpl.nodestore
 libxrpl.nodestore > xrpl.protocol
+libxrpl.peerfinder > xrpl.basics
+libxrpl.peerfinder > xrpl.peerfinder
+libxrpl.peerfinder > xrpl.protocol
 libxrpl.protocol > xrpl.basics
 libxrpl.protocol > xrpl.json
 libxrpl.protocol > xrpl.protocol
 libxrpl.rdb > xrpl.basics
+libxrpl.rdb > xrpl.config
 libxrpl.rdb > xrpl.core
 libxrpl.rdb > xrpl.rdb
 libxrpl.resource > xrpl.basics
@@ -30,6 +42,7 @@ libxrpl.resource > xrpl.json
 libxrpl.resource > xrpl.protocol
 libxrpl.resource > xrpl.resource
 libxrpl.server > xrpl.basics
+libxrpl.server > xrpl.config
 libxrpl.server > xrpl.core
 libxrpl.server > xrpl.json
 libxrpl.server > xrpl.protocol
@@ -51,9 +64,10 @@ libxrpl.tx > xrpl.tx
 test.app > test.jtx
 test.app > test.unit_test
 test.app > xrpl.basics
+test.app > xrpl.config
+test.app > xrpl.consensus
 test.app > xrpl.core
 test.app > xrpld.app
-test.app > xrpld.consensus
 test.app > xrpld.core
 test.app > xrpld.overlay
 test.app > xrpld.rpc
@@ -66,7 +80,6 @@ test.app > xrpl.server
 test.app > xrpl.shamap
 test.app > xrpl.tx
 test.basics > test.jtx
-test.basics > test.unit_test
 test.basics > xrpl.basics
 test.basics > xrpl.core
 test.basics > xrpld.rpc
@@ -75,13 +88,9 @@ test.basics > xrpl.protocol
 test.beast > xrpl.basics
 test.conditions > xrpl.basics
 test.conditions > xrpl.conditions
-test.consensus > test.csf
 test.consensus > test.jtx
-test.consensus > test.toplevel
-test.consensus > test.unit_test
 test.consensus > xrpl.basics
 test.consensus > xrpld.app
-test.consensus > xrpld.consensus
 test.consensus > xrpl.ledger
 test.consensus > xrpl.protocol
 test.consensus > xrpl.shamap
@@ -89,20 +98,18 @@ test.consensus > xrpl.tx
 test.core > test.jtx
 test.core > test.unit_test
 test.core > xrpl.basics
+test.core > xrpl.config
 test.core > xrpl.core
 test.core > xrpld.core
 test.core > xrpl.json
 test.core > xrpl.protocol
 test.core > xrpl.rdb
 test.core > xrpl.server
-test.csf > xrpl.basics
-test.csf > xrpld.consensus
-test.csf > xrpl.json
-test.csf > xrpl.ledger
-test.csf > xrpl.protocol
 test.json > test.jtx
 test.json > xrpl.json
+test.jtx > test.unit_test
 test.jtx > xrpl.basics
+test.jtx > xrpl.config
 test.jtx > xrpl.core
 test.jtx > xrpld.app
 test.jtx > xrpld.core
@@ -123,41 +130,33 @@ test.ledger > xrpl.json
 test.ledger > xrpl.ledger
 test.ledger > xrpl.protocol
 test.nodestore > test.jtx
-test.nodestore > test.unit_test
 test.nodestore > xrpl.basics
 test.nodestore > xrpld.core
 test.nodestore > xrpl.nodestore
-test.nodestore > xrpl.protocol
 test.nodestore > xrpl.rdb
 test.overlay > test.jtx
 test.overlay > test.unit_test
 test.overlay > xrpl.basics
+test.overlay > xrpl.config
 test.overlay > xrpld.app
 test.overlay > xrpld.core
 test.overlay > xrpld.overlay
-test.overlay > xrpld.peerfinder
 test.overlay > xrpl.json
 test.overlay > xrpl.nodestore
+test.overlay > xrpl.peerfinder
 test.overlay > xrpl.protocol
 test.overlay > xrpl.resource
 test.overlay > xrpl.server
 test.overlay > xrpl.shamap
-test.peerfinder > test.beast
-test.peerfinder > test.unit_test
-test.peerfinder > xrpl.basics
-test.peerfinder > xrpld.core
-test.peerfinder > xrpld.peerfinder
-test.peerfinder > xrpl.protocol
 test.protocol > test.jtx
 test.protocol > test.unit_test
 test.protocol > xrpl.basics
+test.protocol > xrpld.core
 test.protocol > xrpl.json
 test.protocol > xrpl.protocol
-test.resource > test.unit_test
-test.resource > xrpl.basics
-test.resource > xrpl.resource
 test.rpc > test.jtx
 test.rpc > xrpl.basics
+test.rpc > xrpl.config
 test.rpc > xrpl.core
 test.rpc > xrpld.app
 test.rpc > xrpld.core
@@ -172,43 +171,52 @@ test.rpc > xrpl.tx
 test.server > test.jtx
 test.server > test.unit_test
 test.server > xrpl.basics
+test.server > xrpl.config
 test.server > xrpld.app
 test.server > xrpld.core
 test.server > xrpl.json
 test.server > xrpl.protocol
 test.server > xrpl.server
-test.shamap > test.unit_test
-test.shamap > xrpl.basics
-test.shamap > xrpl.nodestore
-test.shamap > xrpl.protocol
-test.shamap > xrpl.shamap
-test.toplevel > test.csf
-test.toplevel > xrpl.json
 test.unit_test > xrpl.basics
 test.unit_test > xrpl.protocol
 tests.libxrpl > xrpl.basics
+tests.libxrpl > xrpl.config
+tests.libxrpl > xrpl.consensus
 tests.libxrpl > xrpl.core
 tests.libxrpl > xrpl.json
 tests.libxrpl > xrpl.ledger
 tests.libxrpl > xrpl.net
 tests.libxrpl > xrpl.nodestore
+tests.libxrpl > xrpl.peerfinder
 tests.libxrpl > xrpl.protocol
 tests.libxrpl > xrpl.protocol_autogen
+tests.libxrpl > xrpl.resource
 tests.libxrpl > xrpl.server
 tests.libxrpl > xrpl.shamap
 tests.libxrpl > xrpl.tx
 xrpl.conditions > xrpl.basics
 xrpl.conditions > xrpl.protocol
+xrpl.config > xrpl.basics
+xrpl.consensus > xrpl.basics
+xrpl.consensus > xrpl.json
+xrpl.consensus > xrpl.ledger
+xrpl.consensus > xrpl.protocol
 xrpl.core > xrpl.basics
 xrpl.core > xrpl.json
 xrpl.core > xrpl.protocol
 xrpl.json > xrpl.basics
 xrpl.ledger > xrpl.basics
+xrpl.ledger > xrpl.json
+xrpl.ledger > xrpl.nodestore
 xrpl.ledger > xrpl.protocol
 xrpl.ledger > xrpl.shamap
 xrpl.net > xrpl.basics
 xrpl.nodestore > xrpl.basics
+xrpl.nodestore > xrpl.config
+xrpl.nodestore > xrpl.json
 xrpl.nodestore > xrpl.protocol
+xrpl.peerfinder > xrpl.basics
+xrpl.peerfinder > xrpl.protocol
 xrpl.protocol > xrpl.basics
 xrpl.protocol > xrpl.json
 xrpl.protocol_autogen > xrpl.json
@@ -225,7 +233,6 @@ xrpl.server > xrpl.json
 xrpl.server > xrpl.protocol
 xrpl.server > xrpl.rdb
 xrpl.server > xrpl.resource
-xrpl.server > xrpl.shamap
 xrpl.shamap > xrpl.basics
 xrpl.shamap > xrpl.nodestore
 xrpl.shamap > xrpl.protocol
@@ -235,50 +242,56 @@ xrpl.tx > xrpl.ledger
 xrpl.tx > xrpl.protocol
 xrpld.app > test.unit_test
 xrpld.app > xrpl.basics
+xrpld.app > xrpl.config
+xrpld.app > xrpl.consensus
 xrpld.app > xrpl.core
-xrpld.app > xrpld.consensus
 xrpld.app > xrpld.core
 xrpld.app > xrpl.json
 xrpld.app > xrpl.ledger
 xrpld.app > xrpl.net
 xrpld.app > xrpl.nodestore
+xrpld.app > xrpl.peerfinder
 xrpld.app > xrpl.protocol
 xrpld.app > xrpl.rdb
 xrpld.app > xrpl.resource
 xrpld.app > xrpl.server
 xrpld.app > xrpl.shamap
 xrpld.app > xrpl.tx
-xrpld.consensus > xrpl.basics
-xrpld.consensus > xrpl.json
-xrpld.consensus > xrpl.ledger
-xrpld.consensus > xrpl.protocol
 xrpld.core > xrpl.basics
+xrpld.core > xrpl.config
 xrpld.core > xrpl.core
 xrpld.core > xrpl.net
 xrpld.core > xrpl.protocol
 xrpld.core > xrpl.rdb
 xrpld.overlay > xrpl.basics
+xrpld.overlay > xrpl.config
+xrpld.overlay > xrpl.consensus
 xrpld.overlay > xrpl.core
-xrpld.overlay > xrpld.consensus
 xrpld.overlay > xrpld.core
 xrpld.overlay > xrpld.peerfinder
 xrpld.overlay > xrpl.json
 xrpld.overlay > xrpl.ledger
+xrpld.overlay > xrpl.peerfinder
 xrpld.overlay > xrpl.protocol
 xrpld.overlay > xrpl.resource
 xrpld.overlay > xrpl.server
 xrpld.overlay > xrpl.shamap
 xrpld.overlay > xrpl.tx
 xrpld.peerfinder > xrpl.basics
+xrpld.peerfinder > xrpld.app
 xrpld.peerfinder > xrpld.core
-xrpld.peerfinder > xrpl.protocol
+xrpld.peerfinder > xrpl.peerfinder
 xrpld.peerfinder > xrpl.rdb
 xrpld.perflog > xrpl.basics
+xrpld.perflog > xrpl.config
 xrpld.perflog > xrpl.core
+xrpld.perflog > xrpld.app
 xrpld.perflog > xrpld.rpc
 xrpld.perflog > xrpl.json
+xrpld.perflog > xrpl.nodestore
 xrpld.perflog > xrpl.protocol
 xrpld.rpc > xrpl.basics
+xrpld.rpc > xrpl.config
 xrpld.rpc > xrpl.core
 xrpld.rpc > xrpld.core
 xrpld.rpc > xrpl.json
@@ -293,5 +306,6 @@ xrpld.rpc > xrpl.shamap
 xrpld.rpc > xrpl.tx
 xrpld.shamap > xrpl.basics
 xrpld.shamap > xrpld.core
+xrpld.shamap > xrpl.nodestore
 xrpld.shamap > xrpl.protocol
 xrpld.shamap > xrpl.shamap

.github/scripts/rename/binary.sh

@@ -49,7 +49,7 @@ ${SED_COMMAND} -i -E 's@ripple/xrpld@XRPLF/rippled@g' BUILD.md
 ${SED_COMMAND} -i -E 's@XRPLF/xrpld@XRPLF/rippled@g' BUILD.md
 ${SED_COMMAND} -i -E 's@xrpld \(`xrpld`\)@xrpld@g' BUILD.md
 ${SED_COMMAND} -i -E 's@XRPLF/xrpld@XRPLF/rippled@g' CONTRIBUTING.md
-${SED_COMMAND} -i -E 's@XRPLF/xrpld@XRPLF/rippled@g' docs/build/install.md
+${SED_COMMAND} -i -E 's@XRPLF/xrpld@XRPLF/rippled@g' docs/install.md
 
 popd
 echo "Processing complete."

.github/scripts/rename/cmake.sh

@@ -43,9 +43,6 @@ pushd "${DIRECTORY}"
 # Rename the files.
 find cmake -type f -name 'Rippled*.cmake' -exec bash -c 'mv "${1}" "${1/Rippled/Xrpl}"' - {} \;
 find cmake -type f -name 'Ripple*.cmake' -exec bash -c 'mv "${1}" "${1/Ripple/Xrpl}"' - {} \;
-if [ -e cmake/xrpl_add_test.cmake ]; then
-    mv cmake/xrpl_add_test.cmake cmake/XrplAddTest.cmake
-fi
 if [ -e include/xrpl/proto/ripple.proto ]; then
     mv include/xrpl/proto/ripple.proto include/xrpl/proto/xrpl.proto
 fi
@@ -60,7 +57,6 @@ find cmake -type f -name '*.cmake' | while read -r FILE; do
 done
 ${SED_COMMAND} -i -E 's/Rippled?/Xrpl/g' CMakeLists.txt
 ${SED_COMMAND} -i 's/ripple/xrpl/g' CMakeLists.txt
-${SED_COMMAND} -i 's/include(xrpl_add_test)/include(XrplAddTest)/' src/tests/libxrpl/CMakeLists.txt
 ${SED_COMMAND} -i 's/ripple.pb.h/xrpl.pb.h/' include/xrpl/protocol/messages.h
 ${SED_COMMAND} -i 's/ripple.pb.h/xrpl.pb.h/' BUILD.md
 ${SED_COMMAND} -i 's/ripple.pb.h/xrpl.pb.h/' BUILD.md

.github/scripts/rename/docs.sh

@@ -77,8 +77,8 @@ ${SED_COMMAND} -i 's/Ripple integrators/XRPL developers/' README.md
 ${SED_COMMAND} -i 's/sanitizer-configuration-for-rippled/sanitizer-configuration-for-xrpld/' docs/build/sanitizers.md
 ${SED_COMMAND} -i 's/rippled/xrpld/g' .github/scripts/levelization/README.md
 ${SED_COMMAND} -i 's/rippled/xrpld/g' .github/scripts/strategy-matrix/generate.py
-${SED_COMMAND} -i 's@/rippled@/xrpld@g' docs/build/install.md
-${SED_COMMAND} -i 's@github.com/XRPLF/xrpld@github.com/XRPLF/rippled@g' docs/build/install.md
+${SED_COMMAND} -i 's@/rippled@/xrpld@g' docs/install.md
+${SED_COMMAND} -i 's@github.com/XRPLF/xrpld@github.com/XRPLF/rippled@g' docs/install.md
 ${SED_COMMAND} -i 's/rippled/xrpld/g' docs/Doxyfile
 ${SED_COMMAND} -i 's/ripple_basics/basics/' include/xrpl/basics/CountedObject.h
 ${SED_COMMAND} -i 's/<ripple/<xrpl/' include/xrpl/protocol/AccountID.h

.github/scripts/rename/namespace.sh

@@ -46,9 +46,6 @@ for DIRECTORY in "${DIRECTORIES[@]}"; do
     done
 done
 
-# Special case for NuDBFactory that has ripple twice in the test suite name.
-${SED_COMMAND} -i -E 's/(BEAST_DEFINE_TESTSUITE.+)ripple(.+)/\1xrpl\2/g' src/test/nodestore/NuDBFactory_test.cpp
-
 DIRECTORY=$1
 find "${DIRECTORY}" -type f -name "*.md" | while read -r FILE; do
     echo "Processing file: ${FILE}"

.github/scripts/strategy-matrix/generate.py

@@ -1,384 +1,335 @@
 #!/usr/bin/env python3
 import argparse
+import dataclasses
 import itertools
 import json
-from dataclasses import dataclass
 from pathlib import Path
 
 THIS_DIR = Path(__file__).parent.resolve()
 
+_BASE_CMAKE_ARGS = [
+    "-Dtests=ON",
+    "-Dwerr=ON",
+    "-Dxrpld=ON",
+    "-Dwextra=ON",
+    "-Drust=ON",
+]
 
-@dataclass
-class Config:
-    architecture: list[dict]
-    os: list[dict]
+# Maps sanitizer names (as used in cmake) to short config-name suffixes.
+_SANITIZER_SUFFIX: dict[str, str] = {
+    "address": "asan",
+    "undefinedbehavior": "ubsan",
+    "thread": "tsan",
+}
+
+
+def get_cmake_args(build_type: str, extra_args: str) -> str:
+    """Get the full list of CMake arguments for a config."""
+    args = _BASE_CMAKE_ARGS.copy()
+    if extra_args:
+        args.extend(extra_args.split())
+    return " ".join(args)
+
+
+# ---------------------------------------------------------------------------
+# Input types — shapes of the JSON config files
+# ---------------------------------------------------------------------------
+
+
+# Every config must declare 'minimal'. Minimal configs form the reduced matrix
+# built for pull requests by default; the full matrix adds the rest. Packaging
+# configs declare it too, but packaging is gated in the workflow, not by it.
+#
+# Configs may also opt into 'benchmark' to smoke-run the benchmarks. Note that
+# the flag applies to every entry a config expands into, so only set it on
+# configs that expand to a single combination.
+
+
+@dataclasses.dataclass
+class LinuxConfig:
+    """One entry in linux.json's 'configs' or 'package_configs' arrays."""
+
+    compiler: list[str]
     build_type: list[str]
-    cmake_args: list[str]
+    arch: list[str]
+    minimal: bool
+    benchmark: bool = False  # if true, smoke-run the benchmarks after testing
+    sanitizers: list[str] = dataclasses.field(default_factory=list)
+    suffix: str = ""
+    extra_cmake_args: str = ""
+    image: str = ""  # only used by package_configs entries
 
 
-"""
-Generate a strategy matrix for GitHub Actions CI.
+@dataclasses.dataclass
+class LinuxFile:
+    """Shape of linux.json."""
 
-On each PR commit we will build a selection of Debian, RHEL, Ubuntu, MacOS, and
-Windows configurations, while upon merge into the develop or release branches,
-we will build all configurations, and test most of them.
+    image_tag: str
+    configs: dict[str, list[LinuxConfig]]  # distro → configs
+    package_configs: dict[str, list[LinuxConfig]]  # distro → packaging configs
 
-We will further set additional CMake arguments as follows:
-- All builds will have the `tests`, `werr`, and `xrpld` options.
-- All builds will have the `wextra` option except for GCC 12 and Clang 16.
-- All release builds will have the `assert` option.
-- Certain Debian Bookworm configurations will change the reference fee, enable
-  codecov, and enable voidstar in PRs.
-"""
+    @classmethod
+    def load(cls, path: Path) -> "LinuxFile":
+        data = json.loads(path.read_text())
+
+        def parse(section: dict) -> dict[str, list[LinuxConfig]]:
+            return {
+                distro: [LinuxConfig(**c) for c in cfgs]
+                for distro, cfgs in section.items()
+            }
+
+        return cls(
+            image_tag=data["image_tag"],
+            configs=parse(data["configs"]),
+            package_configs=parse(data.get("package_configs", {})),
+        )
 
 
-def build_config_name(os_entry: dict[str, str], platform: str, build_type: str) -> str:
-    parts = [os_entry["distro_name"]]
-    for key in ("distro_version", "compiler_name", "compiler_version"):
-        if value := os_entry[key]:
-            parts.append(value)
-    parts.append("arm64" if "arm64" in platform else "amd64")
-    parts.append(build_type.lower())
-    return "-".join(parts)
+@dataclasses.dataclass
+class PlatformConfig:
+    """One entry in macos.json's or windows.json's 'configs' array."""
+
+    build_type: list[str]
+    minimal: bool
+    build_only: bool = False  # if true, skip tests (e.g. macos/Windows Debug)
+    benchmark: bool = False  # if true, smoke-run the benchmarks after testing
+    extra_cmake_args: str = ""
+    # "" is the runner's system compiler, "nix" the flake's CI environment.
+    # macOS only: Linux always builds in a Nix image, Windows has no Nix.
+    toolchain: str = ""
+
+    def __post_init__(self) -> None:
+        if isinstance(self.build_type, str):
+            self.build_type = [self.build_type]
 
 
-def generate_packaging_matrix(config: Config) -> list[dict]:
-    """Emit one entry per os entry with `package: true`. Architecture is
-    hardcoded to linux/amd64 here (and the runner is hardcoded at the
-    workflow level) until arm64 packaging is ready.
+@dataclasses.dataclass
+class PlatformFile:
+    """Shape of macos.json and windows.json."""
+
+    platform: str  # e.g. "macos/arm64" or "windows/amd64"
+    runner: list[str]  # GitHub Actions runner labels
+    configs: list[PlatformConfig]
+
+    @classmethod
+    def load(cls, path: Path) -> "PlatformFile":
+        data = json.loads(path.read_text())
+        return cls(
+            platform=data["platform"],
+            runner=data["runner"],
+            configs=[PlatformConfig(**c) for c in data["configs"]],
+        )
+
+
+# ---------------------------------------------------------------------------
+# Output types — shapes of the generated GitHub Actions matrix entries
+# ---------------------------------------------------------------------------
+
+
+@dataclasses.dataclass
+class Architecture:
+    platform: str
+    runner: list[str]
+
+
+@dataclasses.dataclass
+class MatrixEntry:
+    """One entry in the generated build/test strategy matrix."""
+
+    config_name: str
+    cmake_args: str
+    cmake_target: str
+    build_only: bool
+    benchmark: bool
+    build_type: str
+    architecture: Architecture
+    sanitizers: str
+    image: str = ""  # container image; empty for macOS/Windows (runs natively)
+    compiler: str = ""  # compiler name ("gcc" or "clang"); empty for macOS/Windows
+    toolchain: str = ""  # "nix" for the flake's CI environment; see PlatformConfig
+
+
+@dataclasses.dataclass
+class PackagingEntry:
+    """One entry in the generated packaging strategy matrix."""
+
+    xrpld_artifact_name: str
+    validator_keys_artifact_name: str
+    image: str
+    distro: str  # e.g. "debian" or "rhel"; drives package-format-specific steps
+
+
+# ---------------------------------------------------------------------------
+# Matrix expansion
+# ---------------------------------------------------------------------------
+
+_ARCHS: dict[str, Architecture] = {
+    "amd64": Architecture(
+        platform="linux/amd64", runner=["self-hosted", "Linux", "X64", "heavy"]
+    ),
+    "arm64": Architecture(
+        platform="linux/arm64",
+        runner=["self-hosted", "Linux", "ARM64", "heavy-arm64"],
+    ),
+}
+
+
+def expand_linux_matrix(linux: LinuxFile, minimal: bool) -> list[MatrixEntry]:
+    """Expand a LinuxFile into a flat list of matrix entries.
+
+    Each config entry is expanded over the cross-product of its
+    compiler, build_type, sanitizers, and architecture lists. When 'minimal' is
+    true, only configs flagged as minimal are included.
     """
-    return [
-        {
-            "artifact_name": f"xrpld-{build_config_name(os, 'linux/amd64', 'Release')}",
-            "os": os,
-        }
-        for os in config.os
-        if os.get("package", False)
-    ]
+    entries: list[MatrixEntry] = []
 
-
-def generate_strategy_matrix(all: bool, config: Config) -> list[dict]:
-    configurations = []
-    for architecture, os, build_type, cmake_args in itertools.product(
-        config.architecture, config.os, config.build_type, config.cmake_args
-    ):
-        # The default CMake target is 'all' for Linux and MacOS and 'install'
-        # for Windows, but it can get overridden for certain configurations.
-        cmake_target = "install" if os["distro_name"] == "windows" else "all"
-
-        # We build and test all configurations by default, except for Windows in
-        # Debug, because it is too slow, as well as when code coverage is
-        # enabled as that mode already runs the tests.
-        build_only = False
-        if os["distro_name"] == "windows" and build_type == "Debug":
-            build_only = True
-
-        # Only generate a subset of configurations in PRs.
-        if not all:
-            # Debian:
-            # - Bookworm using GCC 13: Debug on linux/amd64, set the reference
-            #   fee to 500 and enable code coverage (which will be done below).
-            # - Bookworm using GCC 15: Debug on linux/amd64, enable Address and
-            #   UB sanitizers (which will be done below).
-            # - Bookworm using Clang 16: Debug on linux/amd64, enable voidstar.
-            # - Bookworm using Clang 17: Release on linux/amd64, set the
-            #   reference fee to 1000.
-            # - Bookworm using Clang 20: Debug on linux/amd64, enable Address
-            #   and UB sanitizers (which will be done below).
-            if os["distro_name"] == "debian":
-                skip = True
-                if os["distro_version"] == "bookworm":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-13"
-                        and build_type == "Debug"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        cmake_args = f"-DUNIT_TEST_REFERENCE_FEE=500 {cmake_args}"
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-15"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-16"
-                        and build_type == "Debug"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        cmake_args = f"-Dvoidstar=ON {cmake_args}"
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-17"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        cmake_args = f"-DUNIT_TEST_REFERENCE_FEE=1000 {cmake_args}"
-                        skip = False
-                elif os["distro_version"] == "trixie":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-22"
-                        and build_type == "Debug"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                if skip:
-                    continue
-
-            # RHEL:
-            # - 9 using GCC 12: Debug and Release on linux/amd64
-            #   (Release is required for RPM packaging).
-            # - 10 using Clang: Release on linux/amd64.
-            if os["distro_name"] == "rhel":
-                skip = True
-                if os["distro_version"] == "9":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
-                        and build_type in ["Debug", "Release"]
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                elif os["distro_version"] == "10":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-any"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                if skip:
-                    continue
-
-            # Ubuntu:
-            # - Jammy using GCC 12: Debug on linux/arm64, Release on
-            #   linux/amd64 (Release is required for DEB packaging).
-            # - Noble using GCC 14: Release on linux/amd64.
-            # - Noble using Clang 18: Debug on linux/amd64.
-            # - Noble using Clang 19: Release on linux/arm64.
-            if os["distro_name"] == "ubuntu":
-                skip = True
-                if os["distro_version"] == "jammy":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
-                        and build_type == "Debug"
-                        and architecture["platform"] == "linux/arm64"
-                    ):
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                elif os["distro_version"] == "noble":
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-14"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-18"
-                        and build_type == "Debug"
-                        and architecture["platform"] == "linux/amd64"
-                    ):
-                        skip = False
-                    if (
-                        f"{os['compiler_name']}-{os['compiler_version']}" == "clang-19"
-                        and build_type == "Release"
-                        and architecture["platform"] == "linux/arm64"
-                    ):
-                        skip = False
-                if skip:
-                    continue
-
-            # MacOS:
-            # - Debug on macos/arm64.
-            if os["distro_name"] == "macos" and not (
-                build_type == "Debug" and architecture["platform"] == "macos/arm64"
-            ):
+    for distro, configs in linux.configs.items():
+        for cfg in configs:
+            if minimal and not cfg.minimal:
                 continue
+            # An empty sanitizers list means "one entry with no sanitizer".
+            effective_sanitizers = cfg.sanitizers or [""]
+            effective_archs = {arch: _ARCHS[arch] for arch in cfg.arch}
 
-            # Windows:
-            # - Release on windows/amd64.
-            if os["distro_name"] == "windows" and not (
-                build_type == "Release" and architecture["platform"] == "windows/amd64"
+            for compiler, build_type, sanitizer, (arch, arch_info) in itertools.product(
+                cfg.compiler,
+                cfg.build_type,
+                effective_sanitizers,
+                effective_archs.items(),
             ):
-                continue
+                name = f"{distro}-{compiler}-{build_type.lower()}-{arch}"
+                suffix_parts = [
+                    s for s in [cfg.suffix, _SANITIZER_SUFFIX.get(sanitizer, "")] if s
+                ]
+                if suffix_parts:
+                    name += "-" + "-".join(suffix_parts)
 
-        # Additional CMake arguments.
-        cmake_args = f"{cmake_args} -Dtests=ON -Dwerr=ON -Dxrpld=ON"
-        if not f"{os['compiler_name']}-{os['compiler_version']}" in [
-            "gcc-12",
-            "clang-16",
-        ]:
-            cmake_args = f"{cmake_args} -Dwextra=ON"
-        if build_type == "Release":
-            cmake_args = f"{cmake_args} -Dassert=ON"
-
-        # We skip all RHEL on arm64 due to a build failure that needs further
-        # investigation.
-        if os["distro_name"] == "rhel" and architecture["platform"] == "linux/arm64":
-            continue
-
-        # We skip all clang 20+ on arm64 due to Boost build error.
-        if (
-            os["compiler_name"] == "clang"
-            and os["compiler_version"].isdigit()
-            and int(os["compiler_version"]) >= 20
-            and architecture["platform"] == "linux/arm64"
-        ):
-            continue
-
-        # Enable code coverage for Debian Bookworm using GCC 13 in Debug on
-        # linux/amd64.
-        if (
-            f"{os['distro_name']}-{os['distro_version']}" == "debian-bookworm"
-            and f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-13"
-            and build_type == "Debug"
-            and architecture["platform"] == "linux/amd64"
-        ):
-            cmake_args = f"{cmake_args} -Dcoverage=ON -Dcoverage_format=xml -DCODE_COVERAGE_VERBOSE=ON -DCMAKE_C_FLAGS=-O0 -DCMAKE_CXX_FLAGS=-O0"
-
-        # Enable unity build for Ubuntu Jammy using GCC 12 in Debug on
-        # linux/amd64.
-        if (
-            f"{os['distro_name']}-{os['distro_version']}" == "ubuntu-jammy"
-            and f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-12"
-            and build_type == "Debug"
-            and architecture["platform"] == "linux/amd64"
-        ):
-            cmake_args = f"{cmake_args} -Dunity=ON"
-
-        # Generate a unique name for the configuration, e.g. macos-arm64-debug
-        # or debian-bookworm-gcc-12-amd64-release.
-        config_name = build_config_name(os, architecture["platform"], build_type)
-        if "-Dcoverage=ON" in cmake_args:
-            config_name += "-coverage"
-        if "-Dunity=ON" in cmake_args:
-            config_name += "-unity"
-
-        # Add the configuration to the list, with the most unique fields first,
-        # so that they are easier to identify in the GitHub Actions UI, as long
-        # names get truncated.
-        # Add Address and UB sanitizers as separate configurations for specific
-        # bookworm distros. Thread sanitizer is currently disabled (see below).
-        # GCC-Asan xrpld-embedded tests are failing because of https://github.com/google/sanitizers/issues/856
-        if (
-            os["distro_version"] == "bookworm"
-            and f"{os['compiler_name']}-{os['compiler_version']}" == "gcc-15"
-        ) or (
-            os["distro_version"] == "trixie"
-            and f"{os['compiler_name']}-{os['compiler_version']}" == "clang-22"
-        ):
-            # Add ASAN and UBSAN configurations for both gcc-15 and clang-22
-            configurations.append(
-                {
-                    "config_name": config_name + "-asan",
-                    "cmake_args": cmake_args,
-                    "cmake_target": cmake_target,
-                    "build_only": build_only,
-                    "build_type": build_type,
-                    "os": os,
-                    "architecture": architecture,
-                    "sanitizers": "address",
-                }
-            )
-            configurations.append(
-                {
-                    "config_name": config_name + "-ubsan",
-                    "cmake_args": cmake_args,
-                    "cmake_target": cmake_target,
-                    "build_only": build_only,
-                    "build_type": build_type,
-                    "os": os,
-                    "architecture": architecture,
-                    "sanitizers": "undefinedbehavior",
-                }
-            )
-            # TSAN is deactivated due to seg faults with latest compilers.
-            activate_tsan = False
-            if activate_tsan:
-                configurations.append(
-                    {
-                        "config_name": config_name + "-tsan-ubsan",
-                        "cmake_args": cmake_args,
-                        "cmake_target": cmake_target,
-                        "build_only": build_only,
-                        "build_type": build_type,
-                        "os": os,
-                        "architecture": architecture,
-                        "sanitizers": "thread,undefinedbehavior",
-                    }
+                entries.append(
+                    MatrixEntry(
+                        config_name=name,
+                        image=f"ghcr.io/xrplf/xrpld/nix-{distro}:{linux.image_tag}",
+                        cmake_args=get_cmake_args(build_type, cfg.extra_cmake_args),
+                        cmake_target="all",
+                        build_only=False,
+                        benchmark=cfg.benchmark,
+                        build_type=build_type,
+                        architecture=arch_info,
+                        sanitizers=sanitizer,
+                        compiler=compiler,
+                    )
+                )
+
+    return entries
+
+
+def expand_linux_packaging(linux: LinuxFile) -> list[PackagingEntry]:
+    """Generate the packaging matrix from a LinuxFile's package_configs section.
+
+    Packaging uses vanilla distro images (debian:bookworm, almalinux:9) instead of
+    the nix-based build images, because deb/rpm tooling (debhelper, rpm-build)
+    is taken from the distro's archive rather than from nixpkgs. Each config
+    entry carries its own 'image'.
+
+    The artifact names must match what the build job uploads: one artifact per
+    binary, each named after the build config.
+    """
+    entries = []
+    for distro, configs in linux.package_configs.items():
+        for cfg in configs:
+            for compiler, build_type in itertools.product(cfg.compiler, cfg.build_type):
+                config_name = f"{distro}-{compiler}-{build_type.lower()}-amd64"
+                entries.append(
+                    PackagingEntry(
+                        xrpld_artifact_name=f"xrpld-{config_name}",
+                        validator_keys_artifact_name=f"validator-keys-{config_name}",
+                        image=cfg.image,
+                        distro=distro,
+                    )
+                )
+
+    return entries
+
+
+def expand_platform_matrix(pf: PlatformFile, minimal: bool) -> list[MatrixEntry]:
+    """Expand a PlatformFile (macOS or Windows) into matrix entries.
+
+    When 'minimal' is true, only configs flagged as minimal are included.
+    """
+    platform_name, arch = pf.platform.split("/")
+    is_windows = platform_name == "windows"
+
+    entries: list[MatrixEntry] = []
+    for cfg in pf.configs:
+        if minimal and not cfg.minimal:
+            continue
+        for build_type in cfg.build_type:
+            name = f"{platform_name}-{arch}-{build_type.lower()}"
+            if cfg.toolchain:
+                name += f"-{cfg.toolchain}"
+            entries.append(
+                MatrixEntry(
+                    config_name=name,
+                    cmake_args=get_cmake_args(build_type, cfg.extra_cmake_args),
+                    cmake_target="install" if is_windows else "all",
+                    build_only=cfg.build_only,
+                    benchmark=cfg.benchmark,
+                    build_type=build_type,
+                    architecture=Architecture(platform=pf.platform, runner=pf.runner),
+                    sanitizers="",
+                    toolchain=cfg.toolchain,
                 )
-        else:
-            configurations.append(
-                {
-                    "config_name": config_name,
-                    "cmake_args": cmake_args,
-                    "cmake_target": cmake_target,
-                    "build_only": build_only,
-                    "build_type": build_type,
-                    "os": os,
-                    "architecture": architecture,
-                    "sanitizers": "",
-                }
             )
-
-    return configurations
+    return entries
 
 
-def read_config(file: Path) -> Config:
-    config = json.loads(file.read_text())
-    if (
-        config["architecture"] is None
-        or config["os"] is None
-        or config["build_type"] is None
-        or config["cmake_args"] is None
-    ):
-        raise Exception("Invalid configuration file.")
-
-    return Config(**config)
+# ---------------------------------------------------------------------------
+# Entry point
+# ---------------------------------------------------------------------------
 
 
 if __name__ == "__main__":
-    parser = argparse.ArgumentParser()
-    parser.add_argument(
-        "-a",
-        "--all",
-        help="Set to generate all configurations (generally used when merging a PR) or leave unset to generate a subset of configurations (generally used when committing to a PR).",
-        action="store_true",
+    parser = argparse.ArgumentParser(
+        description="Generate a CI strategy matrix for all platforms or a specific one."
     )
     parser.add_argument(
         "-c",
         "--config",
-        help="Path to the JSON file containing the strategy matrix configurations.",
-        required=False,
-        type=Path,
+        help="Platform to generate for ('linux', 'macos', or 'windows'). Defaults to all platforms.",
+        choices=["linux", "macos", "windows"],
+        default=None,
     )
     parser.add_argument(
         "-p",
         "--packaging",
-        help="Emit the packaging matrix (derived from the 'package' field on os entries) instead of the build/test matrix.",
+        help="Emit the Linux packaging matrix instead of the build/test matrix.",
+        action="store_true",
+    )
+    parser.add_argument(
+        "-m",
+        "--minimal",
+        help="Emit only the minimal matrix (the configs flagged 'minimal'), "
+        "used for pull requests by default. If omitted, the full matrix is "
+        "emitted.",
         action="store_true",
     )
     args = parser.parse_args()
 
-    matrix = []
-    if args.packaging:
-        config_path = args.config if args.config else THIS_DIR / "linux.json"
-        matrix += generate_packaging_matrix(read_config(config_path))
-    elif args.config is None or args.config == "":
-        matrix += generate_strategy_matrix(
-            args.all, read_config(THIS_DIR / "linux.json")
-        )
-        matrix += generate_strategy_matrix(
-            args.all, read_config(THIS_DIR / "macos.json")
-        )
-        matrix += generate_strategy_matrix(
-            args.all, read_config(THIS_DIR / "windows.json")
-        )
-    else:
-        matrix += generate_strategy_matrix(args.all, read_config(args.config))
+    matrix: list[MatrixEntry] | list[PackagingEntry] = []
 
-    # Generate the strategy matrix.
-    print(f"matrix={json.dumps({'include': matrix})}")
+    if args.packaging:
+        matrix = expand_linux_packaging(LinuxFile.load(THIS_DIR / "linux.json"))
+    else:
+        if args.config in ("linux", None):
+            matrix += expand_linux_matrix(
+                LinuxFile.load(THIS_DIR / "linux.json"), args.minimal
+            )
+        if args.config in ("macos", None):
+            matrix += expand_platform_matrix(
+                PlatformFile.load(THIS_DIR / "macos.json"), args.minimal
+            )
+        if args.config in ("windows", None):
+            matrix += expand_platform_matrix(
+                PlatformFile.load(THIS_DIR / "windows.json"), args.minimal
+            )
+
+    print(f"matrix={json.dumps({'include': [dataclasses.asdict(e) for e in matrix]})}")

.github/scripts/strategy-matrix/linux.json

@@ -1,221 +1,109 @@
 {
-  "architecture": [
-    {
-      "platform": "linux/amd64",
-      "runner": ["self-hosted", "Linux", "X64", "heavy"]
-    },
-    {
-      "platform": "linux/arm64",
-      "runner": ["self-hosted", "Linux", "ARM64", "heavy-arm64"]
-    }
-  ],
-  "os": [
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "gcc",
-      "compiler_version": "12",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "gcc",
-      "compiler_version": "13",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "gcc",
-      "compiler_version": "15",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "clang",
-      "compiler_version": "16",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "clang",
-      "compiler_version": "17",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "clang",
-      "compiler_version": "18",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "clang",
-      "compiler_version": "19",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "bookworm",
-      "compiler_name": "clang",
-      "compiler_version": "20",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "trixie",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "trixie",
-      "compiler_name": "gcc",
-      "compiler_version": "15",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "trixie",
-      "compiler_name": "clang",
-      "compiler_version": "20",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "trixie",
-      "compiler_name": "clang",
-      "compiler_version": "21",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "debian",
-      "distro_version": "trixie",
-      "compiler_name": "clang",
-      "compiler_version": "22",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "8",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "8",
-      "compiler_name": "clang",
-      "compiler_version": "any",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "9",
-      "compiler_name": "gcc",
-      "compiler_version": "12",
-      "image_sha": "4c086b9",
-      "package": true
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "9",
-      "compiler_name": "gcc",
-      "compiler_version": "13",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "9",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "9",
-      "compiler_name": "clang",
-      "compiler_version": "any",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "10",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "rhel",
-      "distro_version": "10",
-      "compiler_name": "clang",
-      "compiler_version": "any",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "jammy",
-      "compiler_name": "gcc",
-      "compiler_version": "12",
-      "image_sha": "4c086b9",
-      "package": true
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "gcc",
-      "compiler_version": "13",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "gcc",
-      "compiler_version": "14",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "clang",
-      "compiler_version": "16",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "clang",
-      "compiler_version": "17",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "clang",
-      "compiler_version": "18",
-      "image_sha": "4c086b9"
-    },
-    {
-      "distro_name": "ubuntu",
-      "distro_version": "noble",
-      "compiler_name": "clang",
-      "compiler_version": "19",
-      "image_sha": "4c086b9"
-    }
-  ],
-  "build_type": ["Debug", "Release"],
-  "cmake_args": [""]
+  "image_tag": "sha-a0074f8",
+  "configs": {
+    "ubuntu": [
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Debug"],
+        "arch": ["amd64"],
+        "minimal": true,
+        "suffix": "coverage",
+        "extra_cmake_args": "-DUNIT_TEST_REFERENCE_FEE=500 -Dcoverage=ON -Dcoverage_format=xml -DCODE_COVERAGE_VERBOSE=ON -DCMAKE_C_FLAGS=-O0 -DCMAKE_CXX_FLAGS=-O0"
+      },
+      {
+        "compiler": ["clang"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": true,
+        "benchmark": true
+      },
+
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false
+      },
+      {
+        "compiler": ["gcc", "clang"],
+        "build_type": ["Debug", "Release"],
+        "arch": ["arm64"],
+        "minimal": false
+      },
+
+      {
+        "compiler": ["gcc", "clang"],
+        "build_type": ["Debug", "Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "sanitizers": ["address", "undefinedbehavior"]
+      },
+
+      {
+        "compiler": ["clang"],
+        "build_type": ["Debug"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "suffix": "voidstar",
+        "extra_cmake_args": "-Dvoidstar=ON"
+      },
+      {
+        "compiler": ["clang"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "suffix": "reffee",
+        "extra_cmake_args": "-DUNIT_TEST_REFERENCE_FEE=1000"
+      },
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Debug"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "suffix": "unity",
+        "extra_cmake_args": "-Dunity=ON"
+      }
+    ],
+
+    "debian": [
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "extra_cmake_args": "-Dvalidator_keys=ON"
+      }
+    ],
+
+    "rhel": [
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "extra_cmake_args": "-Dvalidator_keys=ON"
+      }
+    ]
+  },
+  "package_configs": {
+    "debian": [
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "image": "ghcr.io/xrplf/xrpld/packaging-debian:sha-a6983f8"
+      }
+    ],
+
+    "rhel": [
+      {
+        "compiler": ["gcc"],
+        "build_type": ["Release"],
+        "arch": ["amd64"],
+        "minimal": false,
+        "image": "ghcr.io/xrplf/xrpld/packaging-rhel:sha-a6983f8"
+      }
+    ]
+  }
 }

.github/scripts/strategy-matrix/macos.json

@@ -1,19 +1,30 @@
 {
-  "architecture": [
+  "platform": "macos/arm64",
+  "runner": ["self-hosted", "macOS", "ARM64", "macos-26-apple-clang-21"],
+  "configs": [
     {
-      "platform": "macos/arm64",
-      "runner": ["self-hosted", "macOS", "ARM64", "mac-runner-m1"]
-    }
-  ],
-  "os": [
+      "build_type": "Release",
+      "extra_cmake_args": "-DCMAKE_POLICY_VERSION_MINIMUM=3.5",
+      "minimal": true
+    },
     {
-      "distro_name": "macos",
-      "distro_version": "",
-      "compiler_name": "",
-      "compiler_version": "",
-      "image_sha": ""
+      "build_type": "Debug",
+      "extra_cmake_args": "-DCMAKE_POLICY_VERSION_MINIMUM=3.5",
+      "build_only": true,
+      "minimal": false
+    },
+    {
+      "build_type": "Release",
+      "extra_cmake_args": "-DCMAKE_POLICY_VERSION_MINIMUM=3.5",
+      "toolchain": "nix",
+      "minimal": false
+    },
+    {
+      "build_type": "Debug",
+      "extra_cmake_args": "-DCMAKE_POLICY_VERSION_MINIMUM=3.5",
+      "toolchain": "nix",
+      "build_only": true,
+      "minimal": false
     }
-  ],
-  "build_type": ["Debug", "Release"],
-  "cmake_args": ["-DCMAKE_POLICY_VERSION_MINIMUM=3.5"]
+  ]
 }

.github/scripts/strategy-matrix/windows.json

@@ -1,19 +1,12 @@
 {
-  "architecture": [
+  "platform": "windows/amd64",
+  "runner": ["self-hosted", "Windows", "dev-box-windows-2026"],
+  "configs": [
+    { "build_type": "Release", "minimal": true },
     {
-      "platform": "windows/amd64",
-      "runner": ["self-hosted", "Windows", "devbox"]
+      "build_type": "Debug",
+      "build_only": true,
+      "minimal": false
     }
-  ],
-  "os": [
-    {
-      "distro_name": "windows",
-      "distro_version": "",
-      "compiler_name": "",
-      "compiler_version": "",
-      "image_sha": ""
-    }
-  ],
-  "build_type": ["Debug", "Release"],
-  "cmake_args": [""]
+  ]
 }

.github/workflows/build-nix-image.yml

@@ -1,109 +0,0 @@
-name: Build Nix Docker image
-
-on:
-  push:
-    branches:
-      - develop
-    paths:
-      - ".github/workflows/build-nix-image.yml"
-      - ".github/workflows/reusable-build-docker-image.yml"
-      - "docker/**"
-      - "flake.nix"
-      - "flake.lock"
-      - "nix/**"
-  pull_request:
-    paths:
-      - ".github/workflows/build-nix-image.yml"
-      - ".github/workflows/reusable-build-docker-image.yml"
-      - "docker/**"
-      - "flake.nix"
-      - "flake.lock"
-      - "nix/**"
-  workflow_dispatch:
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-
-defaults:
-  run:
-    shell: bash
-
-jobs:
-  build:
-    name: Build ${{ matrix.distro.name }} (${{ matrix.target.platform }})
-    permissions:
-      contents: read
-      packages: write
-    strategy:
-      fail-fast: false
-      matrix:
-        # The base images are the oldest supported version of each distro
-        # that we want to build images for.
-        distro:
-          - name: nixos
-            base_image: nixos/nix:latest
-          - name: ubuntu
-            base_image: ubuntu:20.04
-          - name: rhel
-            base_image: registry.access.redhat.com/ubi9/ubi:latest
-          - name: debian
-            base_image: debian:bookworm
-        target:
-          - platform: linux/amd64
-            runner: ubuntu-latest
-          - platform: linux/arm64
-            runner: ubuntu-24.04-arm
-    uses: ./.github/workflows/reusable-build-docker-image.yml
-    with:
-      image_name: ghcr.io/xrplf/xrpld/nix-${{ matrix.distro.name }}
-      dockerfile: docker/nix.Dockerfile
-      base_image: ${{ matrix.distro.base_image }}
-      platform: ${{ matrix.target.platform }}
-      runner: ${{ matrix.target.runner }}
-      push: ${{ github.repository == 'XRPLF/rippled' && github.event_name == 'push' }}
-
-  merge:
-    name: Merge ${{ matrix.distro }} manifest
-    needs: build
-    if: ${{ github.repository == 'XRPLF/rippled' && github.event_name == 'push' }}
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      packages: write
-    strategy:
-      fail-fast: false
-      matrix:
-        distro: [nixos, ubuntu, rhel, debian]
-    env:
-      IMAGE_NAME: ghcr.io/xrplf/xrpld/nix-${{ matrix.distro }}
-
-    steps:
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@d7f5e7f509e45cec5c76c4d5afdd7de93d0b3df5 # v4.1.0
-
-      - name: Docker metadata
-        id: meta
-        uses: docker/metadata-action@80c7e94dd9b9319bd5eb7a0e0fe9291e23a2a2e9 # v6.1.0
-        with:
-          images: ${{ env.IMAGE_NAME }}
-          tags: |
-            type=sha,prefix=sha-,format=short
-            type=raw,value=latest
-
-      - name: Login to GitHub Container Registry
-        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
-        with:
-          registry: ghcr.io
-          username: ${{ github.repository_owner }}
-          password: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Create multi-arch manifests
-        run: |
-          for tag in $(jq -cr '.tags[]' <<<"$DOCKER_METADATA_OUTPUT_JSON"); do
-              docker buildx imagetools create -t "$tag" "${tag}-amd64" "${tag}-arm64"
-          done
-
-      - name: Inspect image
-        run: |
-          docker buildx imagetools inspect "${IMAGE_NAME}:${{ steps.meta.outputs.version }}"

.github/workflows/build-nix-images.yml

@@ -0,0 +1,66 @@
+name: Build `nix` Docker images
+
+on:
+  push:
+    branches:
+      - develop
+    paths:
+      - ".github/workflows/build-nix-images.yml"
+      - "flake.nix"
+      - "flake.lock"
+      - "rust-toolchain.toml"
+      - "nix/**"
+      - "!nix/docker/README.md"
+      - "!nix/devshell.nix"
+      - "bin/check-tools.sh"
+      - "bin/default-loader-path.sh"
+      - "bin/install-sanitizer-libs.sh"
+  pull_request:
+    paths:
+      - ".github/workflows/build-nix-images.yml"
+      - "flake.nix"
+      - "flake.lock"
+      - "rust-toolchain.toml"
+      - "nix/**"
+      - "!nix/docker/README.md"
+      - "!nix/devshell.nix"
+      - "bin/check-tools.sh"
+      - "bin/default-loader-path.sh"
+      - "bin/install-sanitizer-libs.sh"
+  workflow_dispatch:
+
+concurrency:
+  # Read `on-trigger.yml` for the rationale behind this concurrency group name.
+  group: ${{ github.workflow }}-${{ github.event_name == 'push' && github.ref == 'refs/heads/develop' && github.sha || github.ref }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  build-merge:
+    name: Build and push `nix-${{ matrix.distro.name }}` image
+    permissions:
+      contents: read
+      packages: write
+    strategy:
+      fail-fast: false
+      matrix:
+        # The base images are the oldest supported version of each distro
+        # that we want to build images for.
+        distro:
+          - name: nixos
+            base_image: nixos/nix:latest
+          - name: ubuntu
+            base_image: ubuntu:20.04
+          - name: debian
+            base_image: debian:bookworm
+          - name: rhel
+            base_image: registry.access.redhat.com/ubi9/ubi:latest
+    uses: XRPLF/actions/.github/workflows/build-multiarch-image.yml@9e7e4e80af9e684c116b38369add8eea64451f32
+    with:
+      image_name: xrpld/nix-${{ matrix.distro.name }}
+      dockerfile: nix/docker/Dockerfile
+      base_image: ${{ matrix.distro.base_image }}
+      push: ${{ github.event_name == 'push' }}

.github/workflows/build-packaging-images.yml

@@ -0,0 +1,47 @@
+name: Build `packaging` Docker images
+
+on:
+  push:
+    branches:
+      - develop
+    paths:
+      - ".github/workflows/build-packaging-images.yml"
+      - "package/Dockerfile"
+      - "package/install-packaging-tools.sh"
+  pull_request:
+    paths:
+      - ".github/workflows/build-packaging-images.yml"
+      - "package/Dockerfile"
+      - "package/install-packaging-tools.sh"
+  workflow_dispatch:
+
+concurrency:
+  # Read `on-trigger.yml` for the rationale behind this concurrency group name.
+  group: ${{ github.workflow }}-${{ github.event_name == 'push' && github.ref == 'refs/heads/develop' && github.sha || github.ref }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  build-merge:
+    name: Build and push `packaging-${{ matrix.distro.name }}` image
+    permissions:
+      contents: read
+      packages: write
+    strategy:
+      fail-fast: false
+      matrix:
+        distro:
+          - name: debian
+            base_image: debian:bookworm
+          # AlmaLinux rather than UBI9, which does not ship rpm-sign.
+          - name: rhel
+            base_image: almalinux:9
+    uses: XRPLF/actions/.github/workflows/build-multiarch-image.yml@9e7e4e80af9e684c116b38369add8eea64451f32
+    with:
+      image_name: xrpld/packaging-${{ matrix.distro.name }}
+      dockerfile: package/Dockerfile
+      base_image: ${{ matrix.distro.base_image }}
+      push: ${{ github.event_name == 'push' }}

.github/workflows/build-pre-commit-image.yml

@@ -0,0 +1,38 @@
+name: Build `pre-commit` Docker image
+
+on:
+  push:
+    branches:
+      - develop
+    paths:
+      - ".github/workflows/build-pre-commit-image.yml"
+      - "bin/pre-commit/Dockerfile"
+      - "rust-toolchain.toml"
+  pull_request:
+    paths:
+      - ".github/workflows/build-pre-commit-image.yml"
+      - "bin/pre-commit/Dockerfile"
+      - "rust-toolchain.toml"
+  workflow_dispatch:
+
+concurrency:
+  # Read `on-trigger.yml` for the rationale behind this concurrency group name.
+  group: ${{ github.workflow }}-${{ github.event_name == 'push' && github.ref == 'refs/heads/develop' && github.sha || github.ref }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  build-merge:
+    name: Build and push `pre-commit` image
+    permissions:
+      contents: read
+      packages: write
+    uses: XRPLF/actions/.github/workflows/build-multiarch-image.yml@9e7e4e80af9e684c116b38369add8eea64451f32
+    with:
+      image_name: xrpld/pre-commit
+      dockerfile: bin/pre-commit/Dockerfile
+      base_image: ubuntu:26.04
+      push: ${{ github.event_name == 'push' }}

.github/workflows/cargo-audit.yml

@@ -0,0 +1,80 @@
+name: Cargo audit
+
+on:
+  schedule:
+    # 06:32 UTC every Monday.
+    - cron: "32 6 * * 1"
+  push:
+    branches:
+      - "develop"
+      - "release/*"
+    paths:
+      - "crates/**/Cargo.toml"
+      - "crates/Cargo.lock"
+      - ".github/workflows/cargo-audit.yml"
+  pull_request:
+    paths:
+      - "crates/**/Cargo.toml"
+      - "crates/Cargo.lock"
+      - ".github/workflows/cargo-audit.yml"
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+    working-directory: crates
+
+permissions:
+  contents: read
+
+jobs:
+  audit:
+    runs-on: ubuntu-latest
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
+    permissions:
+      contents: read
+      # Needed to open an issue on scheduled failures.
+      issues: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Run cargo audit
+        id: audit
+        continue-on-error: true
+        run: |
+          set -o pipefail
+          cargo audit | tee /tmp/cargo-audit.txt
+
+      - name: Prepare issue body
+        if: ${{ steps.audit.outcome != 'success' && github.event_name == 'schedule' }}
+        run: |
+          {
+              echo "## \`cargo audit\` found advisories"
+              echo
+              echo '```'
+              cat /tmp/cargo-audit.txt
+              echo '```'
+              echo
+              echo "---"
+              echo "*This issue was automatically created by the cargo-audit workflow.*"
+          } >/tmp/cargo-audit-issue.md
+
+      - name: Create issue
+        if: ${{ steps.audit.outcome != 'success' && github.event_name == 'schedule' }}
+        uses: XRPLF/actions/create-issue@2b8bc36af85b88bca0dd7bfac2e2dc05f94ad712
+        with:
+          title: "cargo audit found vulnerabilities"
+          body_file: /tmp/cargo-audit-issue.md
+          labels: "Bug,Security"
+
+      - name: Fail if advisories were found
+        if: ${{ steps.audit.outcome != 'success' }}
+        run: |
+          echo "cargo audit found advisories!"
+          cat /tmp/cargo-audit.txt
+          exit 1

.github/workflows/check-pr-description.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Write PR body to file
         env:

.github/workflows/check-pr-title.yml

@@ -20,4 +20,4 @@ on:
 jobs:
   check_title:
     if: ${{ github.event.pull_request.draft != true }}
-    uses: XRPLF/actions/.github/workflows/check-pr-title.yml@cba1f0891650baf1a9c88624dc2d72573be2eb81
+    uses: XRPLF/actions/.github/workflows/check-pr-title.yml@d7c65e49225a38f6d8010eacf017bb5a98d7476c

.github/workflows/check-tools.yml

@@ -0,0 +1,114 @@
+# Verifies the committed snapshots of `bin/check-tools.sh` output for each Nix
+# environment (see nix/check-tools/). If the environment changes — a new image
+# tag, an updated flake.lock, a different tool list — without the matching
+# snapshot being regenerated and committed, this workflow fails so the drift is
+# caught in review.
+#
+# To regenerate the snapshots, see nix/check-tools/README.md.
+name: Check tools
+
+on:
+  pull_request:
+    paths:
+      - ".github/workflows/check-tools.yml"
+      - ".github/scripts/strategy-matrix/linux.json"
+      - "bin/check-tools.sh"
+      - "nix/**"
+      - "flake.nix"
+      - "flake.lock"
+      - "rust-toolchain.toml"
+  push:
+    branches:
+      - "develop"
+    paths:
+      - ".github/workflows/check-tools.yml"
+      - ".github/scripts/strategy-matrix/linux.json"
+      - "bin/check-tools.sh"
+      - "nix/**"
+      - "flake.nix"
+      - "flake.lock"
+      - "rust-toolchain.toml"
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  # The nix-nixos image tag is pinned alongside the build matrix in linux.json,
+  # so snapshots are checked against the exact image CI builds against.
+  linux-image-tag:
+    runs-on: ubuntu-latest
+    outputs:
+      tag: ${{ steps.tag.outputs.tag }}
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Read nix image tag
+        id: tag
+        run: echo "tag=$(jq -r .image_tag .github/scripts/strategy-matrix/linux.json)" >>"${GITHUB_OUTPUT}"
+
+  # One job for all environments; they differ only in whether the tools come
+  # from the nix-nixos container (Linux) or `nix develop` (macOS).
+  check-tools:
+    needs: linux-image-tag
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runner: ubuntu-latest
+            snapshot: nix/check-tools/nix-ubuntu-amd64.txt
+            nix_develop: false
+          - runner: ubuntu-24.04-arm
+            snapshot: nix/check-tools/nix-ubuntu-arm64.txt
+            nix_develop: false
+          - runner: macos-26-apple-clang-21
+            snapshot: nix/check-tools/macos.txt
+            nix_develop: true
+    runs-on: ${{ matrix.runner }}
+    # Linux runs inside the pinned nix-nixos image; macOS runs natively and uses
+    # the flake's dev shell instead (see the run step below).
+    container: ${{ !matrix.nix_develop && format('ghcr.io/xrplf/xrpld/nix-ubuntu:{0}', needs.linux-image-tag.outputs.tag) || null }}
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Prepare runner
+        uses: XRPLF/actions/prepare-runner@51af40f99ea91a08c3528ddf16d98132dcc7e63c
+        with:
+          enable_ccache: false
+
+      - name: Regenerate snapshot
+        env:
+          CHECK_TOOLS_SKIP_CLONE: "1"
+          # check-tools.sh skips some macOS tools when CI is set; the snapshots
+          # capture the full `nix develop` environment, so unset it here.
+          CI: ""
+        run: |
+          if [ "${{ matrix.nix_develop }}" = "true" ]; then
+              # `nix develop` prints the dev-shell greeting first; keep only the
+              # check-tools.sh output (from the "Detected OS:" line onward).
+              nix --extra-experimental-features "nix-command flakes" develop \
+                  -c bash bin/check-tools.sh | sed -n '/^Detected OS:/,$p' >"${{ matrix.snapshot }}"
+          else
+              bash bin/check-tools.sh >"${{ matrix.snapshot }}"
+          fi
+
+      - name: Verify snapshot is up to date
+        run: |
+          if ! git diff --exit-code -- "${{ matrix.snapshot }}"; then
+              echo "::error::${{ matrix.snapshot }} is out of date. Regenerate it (see nix/check-tools/README.md) and commit the result."
+              exit 1
+          fi
+
+      - name: Upload regenerated snapshot
+        if: failure()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: check-tools-${{ runner.os }}-${{ runner.arch }}
+          path: ${{ matrix.snapshot }}

.github/workflows/conflicting-pr.yml

@@ -14,10 +14,11 @@ permissions:
 
 jobs:
   main:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'IgnoreConflicts') }}
     runs-on: ubuntu-latest
     steps:
       - name: Check if PRs are dirty
-        uses: eps1lon/actions-label-merge-conflict@1df065ebe6e3310545d4f4c4e862e43bdca146f0 # v3.0.3
+        uses: eps1lon/actions-label-merge-conflict@0273be72a0bbd58fcd71d0d6c02c209b50d1e5e1 # v3.1.0
         with:
           dirtyLabel: "PR: has conflicts"
           repoToken: "${{ secrets.GITHUB_TOKEN }}"

.github/workflows/on-pr.yml

@@ -1,7 +1,11 @@
-# This workflow runs all workflows to check, build and test the project on
-# various Linux flavors, as well as on MacOS and Windows, on every push to a
-# user branch. However, it will not run if the pull request is a draft unless it
-# has the 'DraftRunCI' label. For commits to PRs that target a release branch,
+# This workflow runs workflows to check, build and test the project
+# on every meaningful change on pull_request.
+# However, it will not run if the PR is a draft
+# unless it has the 'DraftRunCI' or 'Full CI build' label.
+#
+# By default a PR builds only a minimal matrix.
+# The full matrix runs once the PR is labeled "Ready to merge" or "Full CI build".
+# For commits to PRs that target a release branch,
 # it also uploads the libxrpl recipe to the Conan remote.
 name: PR
 
@@ -15,8 +19,16 @@ on:
       - reopened
       - synchronize
       - ready_for_review
+      # Trigger on label changes so toggling "Ready to merge" or "Full CI build"
+      # switches between the minimal and full matrix without needing a new push.
+      - labeled
+      - unlabeled
 
 concurrency:
+  # A single per-ref group with cancel-in-progress means any newer run (a push
+  # or a label change) supersedes the in-progress one for that ref. Keeping
+  # exactly one authoritative run per ref ensures a fast do-nothing run can never
+  # mask a real build's checks.
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
@@ -25,15 +37,22 @@ defaults:
     shell: bash
 
 jobs:
-  # This job determines whether the rest of the workflow should run. It runs
-  # when the PR is not a draft (which should also cover merge-group) or
-  # has the 'DraftRunCI' label.
+  # This job determines whether the rest of the workflow should run at all,
+  # based on the current set of labels: it runs when the PR is not a draft
+  # (which should also cover merge-group) or has the 'DraftRunCI' or
+  # 'Full CI build' label. Whether a build then happens, and whether it is the
+  # minimal or full matrix, is decided further below and in the strategy matrix.
   should-run:
-    if: ${{ !github.event.pull_request.draft || contains(github.event.pull_request.labels.*.name, 'DraftRunCI') }}
+    if: >-
+      ${{
+        !github.event.pull_request.draft
+        || contains(github.event.pull_request.labels.*.name, 'DraftRunCI')
+        || contains(github.event.pull_request.labels.*.name, 'Full CI build')
+      }}
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Determine changed files
         # This step checks whether any files have changed that should
         # cause the next jobs to run. We do it this way rather than
@@ -58,21 +77,28 @@ jobs:
 
             # Keep the paths below in sync with those in `on-trigger.yml`.
             .github/actions/build-deps/**
-            .github/actions/generate-version/**
+            .github/actions/release-info/**
             .github/actions/setup-conan/**
+            .github/actions/setup-nix-env/**
             .github/scripts/strategy-matrix/**
             .github/workflows/reusable-build-test-config.yml
             .github/workflows/reusable-build-test.yml
+            .github/workflows/reusable-check-autogen.yml
             .github/workflows/reusable-clang-tidy.yml
             .github/workflows/reusable-package.yml
+            .github/workflows/reusable-rust.yml
             .github/workflows/reusable-strategy-matrix.yml
             .github/workflows/reusable-test.yml
             .github/workflows/reusable-upload-recipe.yml
             .clang-tidy
             .codecov.yml
+            bin/check-nix-store-refs.sh
+            bin/check-tools.sh
+            bin/default-loader-path.sh
             cfg/**
             cmake/**
             conan/**
+            crates/**
             external/**
             include/**
             src/**
@@ -80,6 +106,9 @@ jobs:
             CMakeLists.txt
             conanfile.py
             conan.lock
+            flake.lock
+            flake.nix
+            nix/**
             LICENSE.md
             package/**
             README.md
@@ -90,19 +119,26 @@ jobs:
         # least one of:
         # * Any of the files checked in the `changes` step were modified
         # * The PR is NOT a draft and is labeled "Ready to merge"
+        # * The PR is labeled "Full CI build" (draft or not)
         # * The workflow is running from the merge queue
         id: go
         env:
           FILES: ${{ steps.changes.outputs.any_changed }}
           DRAFT: ${{ github.event.pull_request.draft }}
           READY: ${{ contains(github.event.pull_request.labels.*.name, 'Ready to merge') }}
+          FULL: ${{ contains(github.event.pull_request.labels.*.name, 'Full CI build') }}
           MERGE: ${{ github.event_name == 'merge_group' }}
         run: |
-          echo "go=${{ (env.DRAFT != 'true' && env.READY == 'true') || env.FILES == 'true' || env.MERGE == 'true' }}" >>"${GITHUB_OUTPUT}"
+          echo "go=${{ (env.DRAFT != 'true' && env.READY == 'true') || env.FULL == 'true' || env.FILES == 'true' || env.MERGE == 'true' }}" >>"${GITHUB_OUTPUT}"
           cat "${GITHUB_OUTPUT}"
     outputs:
       go: ${{ steps.go.outputs.go == 'true' }}
 
+  check-autogen:
+    needs: should-run
+    if: ${{ needs.should-run.outputs.go == 'true' }}
+    uses: ./.github/workflows/reusable-check-autogen.yml
+
   check-levelization:
     needs: should-run
     if: ${{ needs.should-run.outputs.go == 'true' }}
@@ -121,7 +157,6 @@ jobs:
       issues: write
       contents: read
     with:
-      check_only_changed: true
       create_issue_on_failure: false
 
   build-test:
@@ -140,9 +175,19 @@ jobs:
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
 
+  rust:
+    needs: should-run
+    if: ${{ needs.should-run.outputs.go == 'true' }}
+    uses: ./.github/workflows/reusable-rust.yml
+    secrets:
+      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+
   package:
     needs: [should-run, build-test]
-    if: ${{ needs.should-run.outputs.go == 'true' }}
+    # Packaging consumes the debian/rhel release binaries, which are only built
+    # by the full matrix. Skip it for pull requests that ran only the minimal
+    # matrix (i.e. not yet labeled "Ready to merge" or "Full CI build").
+    if: ${{ needs.should-run.outputs.go == 'true' && (github.event_name != 'pull_request' || contains(github.event.pull_request.labels.*.name, 'Ready to merge') || contains(github.event.pull_request.labels.*.name, 'Full CI build')) }}
     uses: ./.github/workflows/reusable-package.yml
 
   upload-recipe:
@@ -153,8 +198,8 @@ jobs:
     if: ${{ github.repository == 'XRPLF/rippled' && needs.should-run.outputs.go == 'true' && github.event_name == 'pull_request' && startsWith(github.event.pull_request.base.ref, 'release') }}
     uses: ./.github/workflows/reusable-upload-recipe.yml
     secrets:
-      remote_username: ${{ secrets.CONAN_REMOTE_USERNAME }}
-      remote_password: ${{ secrets.CONAN_REMOTE_PASSWORD }}
+      remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+      remote_password: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
 
   notify-clio:
     needs: upload-recipe
@@ -175,10 +220,12 @@ jobs:
   passed:
     if: failure() || cancelled()
     needs:
+      - check-autogen
       - check-levelization
       - check-rename
       - clang-tidy
       - build-test
+      - rust
       - package
       - upload-recipe
       - notify-clio

.github/workflows/on-tag.yml

@@ -1,5 +1,9 @@
-# This workflow uploads the libxrpl recipe to the Conan remote and builds
-# release packages when a versioned tag is pushed.
+# When a versioned tag is pushed, this workflow:
+#
+#   - uploads the libxrpl recipe to the Conan remote
+#   - builds and tests the release binaries
+#   - builds the DEB and RPM packages
+#   - publishes those packages to the XRPLF package repositories
 name: Tag
 
 on:
@@ -20,11 +24,11 @@ jobs:
     if: ${{ github.repository == 'XRPLF/rippled' }}
     uses: ./.github/workflows/reusable-upload-recipe.yml
     secrets:
-      remote_username: ${{ secrets.CONAN_REMOTE_USERNAME }}
-      remote_password: ${{ secrets.CONAN_REMOTE_PASSWORD }}
+      remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+      remote_password: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
 
   build-test:
-    if: ${{ github.repository == 'XRPLF/rippled' }}
+    if: ${{ github.repository_owner == 'XRPLF' }}
     uses: ./.github/workflows/reusable-build-test.yml
     strategy:
       fail-fast: true
@@ -33,11 +37,16 @@ jobs:
     with:
       ccache_enabled: false
       os: ${{ matrix.os }}
-      strategy_matrix: minimal
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
 
   package:
-    if: ${{ github.repository == 'XRPLF/rippled' }}
+    if: ${{ github.repository_owner == 'XRPLF' }}
     needs: build-test
     uses: ./.github/workflows/reusable-package.yml
+    with:
+      publish: true
+    secrets:
+      remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+      remote_password: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
+      signing_key: ${{ secrets.NEXUS_PACKAGES_PRIVATE_KEY }}

.github/workflows/on-trigger.yml

@@ -15,21 +15,28 @@ on:
 
       # Keep the paths below in sync with those in `on-pr.yml`.
       - ".github/actions/build-deps/**"
-      - ".github/actions/generate-version/**"
+      - ".github/actions/release-info/**"
       - ".github/actions/setup-conan/**"
+      - ".github/actions/setup-nix-env/**"
       - ".github/scripts/strategy-matrix/**"
       - ".github/workflows/reusable-build-test-config.yml"
       - ".github/workflows/reusable-build-test.yml"
+      - ".github/workflows/reusable-check-autogen.yml"
       - ".github/workflows/reusable-clang-tidy.yml"
       - ".github/workflows/reusable-package.yml"
+      - ".github/workflows/reusable-rust.yml"
       - ".github/workflows/reusable-strategy-matrix.yml"
       - ".github/workflows/reusable-test.yml"
       - ".github/workflows/reusable-upload-recipe.yml"
       - ".clang-tidy"
       - ".codecov.yml"
+      - "bin/check-nix-store-refs.sh"
+      - "bin/check-tools.sh"
+      - "bin/default-loader-path.sh"
       - "cfg/**"
       - "cmake/**"
       - "conan/**"
+      - "crates/**"
       - "external/**"
       - "include/**"
       - "src/**"
@@ -37,6 +44,9 @@ on:
       - "CMakeLists.txt"
       - "conanfile.py"
       - "conan.lock"
+      - "flake.lock"
+      - "flake.nix"
+      - "nix/**"
       - "LICENSE.md"
       - "package/**"
       - "README.md"
@@ -65,13 +75,15 @@ defaults:
     shell: bash
 
 jobs:
+  check-autogen:
+    uses: ./.github/workflows/reusable-check-autogen.yml
+
   clang-tidy:
     uses: ./.github/workflows/reusable-clang-tidy.yml
     permissions:
       issues: write
       contents: read
     with:
-      check_only_changed: false
       create_issue_on_failure: ${{ github.event_name == 'schedule' }}
 
   build-test:
@@ -88,7 +100,11 @@ jobs:
       # not identical to a regular compilation.
       ccache_enabled: ${{ github.repository_owner == 'XRPLF' && !startsWith(github.ref, 'refs/heads/release') }}
       os: ${{ matrix.os }}
-      strategy_matrix: ${{ github.event_name == 'schedule' && 'all' || 'minimal' }}
+    secrets:
+      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+
+  rust:
+    uses: ./.github/workflows/reusable-rust.yml
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
 
@@ -98,9 +114,17 @@ jobs:
     if: ${{ github.repository == 'XRPLF/rippled' && github.event_name == 'push' && github.ref == 'refs/heads/develop' }}
     uses: ./.github/workflows/reusable-upload-recipe.yml
     secrets:
-      remote_username: ${{ secrets.CONAN_REMOTE_USERNAME }}
-      remote_password: ${{ secrets.CONAN_REMOTE_PASSWORD }}
+      remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+      remote_password: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
 
   package:
     needs: build-test
     uses: ./.github/workflows/reusable-package.yml
+    with:
+      # Packages are built on every trigger; only develop pushes in XRPLF/rippled
+      # publish them, matching upload-recipe above.
+      publish: ${{ github.repository == 'XRPLF/rippled' && github.event_name == 'push' && github.ref == 'refs/heads/develop' }}
+    secrets:
+      remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+      remote_password: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
+      signing_key: ${{ secrets.NEXUS_PACKAGES_PRIVATE_KEY }}

.github/workflows/pre-commit.yml

@@ -14,7 +14,7 @@ on:
 jobs:
   # Call the workflow in the XRPLF/actions repo that runs the pre-commit hooks.
   run-hooks:
-    uses: XRPLF/actions/.github/workflows/pre-commit.yml@cba1f0891650baf1a9c88624dc2d72573be2eb81
+    uses: XRPLF/actions/.github/workflows/pre-commit.yml@3ba08d6ddf114092891d48491fc2e26c3ba15552
     with:
       runs_on: ubuntu-latest
-      container: '{ "image": "ghcr.io/xrplf/ci/tools-rippled-pre-commit:sha-41ec7c1" }'
+      container: '{ "image": "ghcr.io/xrplf/xrpld/pre-commit:sha-f56b79f" }'

.github/workflows/publish-docs.yml

@@ -41,13 +41,13 @@ env:
 jobs:
   build:
     runs-on: ubuntu-latest
-    container: ghcr.io/xrplf/ci/tools-rippled-documentation:sha-a8c7be1
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Prepare runner
-        uses: XRPLF/actions/prepare-runner@90f11ee655d1687824fb8793db770477d52afbab
+        uses: XRPLF/actions/prepare-runner@51af40f99ea91a08c3528ddf16d98132dcc7e63c
         with:
           enable_ccache: false
 
@@ -57,19 +57,11 @@ jobs:
         with:
           subtract: ${{ env.NPROC_SUBTRACT }}
 
-      - name: Check configuration
-        run: |
-          echo 'Checking path.'
-          echo ${PATH} | tr ':' '\n'
+      - name: Print build environment
+        uses: XRPLF/actions/print-build-env@59dec886e4afb05a1724443af08baccbc045b574
 
-          echo 'Checking environment variables.'
-          env | sort
-
-          echo 'Checking CMake version.'
-          cmake --version
-
-          echo 'Checking Doxygen version.'
-          doxygen --version
+      - name: Check Doxygen version
+        run: doxygen --version
 
       - name: Build documentation
         env:

.github/workflows/reusable-build-docker-image.yml

@@ -1,89 +0,0 @@
-# Build a single-platform Docker image. On push, the image is pushed to
-# GHCR with arch-suffixed tags (e.g. `:latest-amd64`, `:sha-abc-amd64`)
-# so the calling workflow can stitch per-arch builds into a multi-arch
-# manifest without needing to pass digests around.
-name: Reusable build Docker image (single platform)
-
-on:
-  workflow_call:
-    inputs:
-      image_name:
-        description: "Full image name without tag (e.g. 'ghcr.io/xrplf/xrpld/nix-ubuntu')"
-        required: true
-        type: string
-      dockerfile:
-        description: "Path to the Dockerfile, relative to the repository root"
-        required: true
-        type: string
-      base_image:
-        description: "Value passed to the Dockerfile as the BASE_IMAGE build arg"
-        required: true
-        type: string
-      platform:
-        description: "Docker platform string, e.g. linux/amd64"
-        required: true
-        type: string
-      runner:
-        description: "GitHub Actions runner label to build on"
-        required: true
-        type: string
-      push:
-        description: "Whether to push the image to GHCR"
-        required: true
-        type: boolean
-
-defaults:
-  run:
-    shell: bash
-
-jobs:
-  build:
-    name: Build (${{ inputs.platform }})
-    runs-on: ${{ inputs.runner }}
-    permissions:
-      contents: read
-      packages: write
-
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-
-      - name: Determine arch
-        id: vars
-        env:
-          PLATFORM: ${{ inputs.platform }}
-        run: |
-          echo "arch=${PLATFORM##*/}" >>$GITHUB_OUTPUT
-
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@d7f5e7f509e45cec5c76c4d5afdd7de93d0b3df5 # v4.1.0
-
-      - name: Login to GitHub Container Registry
-        if: inputs.push
-        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
-        with:
-          registry: ghcr.io
-          username: ${{ github.repository_owner }}
-          password: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Docker metadata
-        id: meta
-        uses: docker/metadata-action@80c7e94dd9b9319bd5eb7a0e0fe9291e23a2a2e9 # v6.1.0
-        with:
-          images: ${{ inputs.image_name }}
-          tags: |
-            type=sha,prefix=sha-,format=short
-            type=raw,value=latest
-          flavor: |
-            suffix=-${{ steps.vars.outputs.arch }},onlatest=true
-
-      - name: Build and push
-        uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v7.2.0
-        with:
-          context: .
-          file: ${{ inputs.dockerfile }}
-          platforms: ${{ inputs.platform }}
-          push: ${{ inputs.push }}
-          tags: ${{ steps.meta.outputs.tags }}
-          labels: ${{ steps.meta.outputs.labels }}
-          build-args: BASE_IMAGE=${{ inputs.base_image }}

.github/workflows/reusable-build-test-config.yml

@@ -3,6 +3,12 @@ name: Build and test configuration
 on:
   workflow_call:
     inputs:
+      benchmark:
+        description: "Whether to smoke-run the benchmarks after testing."
+        required: false
+        type: boolean
+        default: false
+
       build_only:
         description: 'Whether to only build or to build and test the code ("true", "false").'
         required: true
@@ -57,6 +63,18 @@ on:
         type: string
         default: ""
 
+      compiler:
+        description: 'The compiler to use ("gcc" or "clang"). Leave empty for macOS/Windows (uses system default).'
+        required: false
+        type: string
+        default: ""
+
+      toolchain:
+        description: 'Where the toolchain comes from ("nix" to build the flake CI environment on the runner, empty for the system one). macOS only: Linux always builds in a Nix image, and Nix has no Windows support.'
+        required: false
+        type: string
+        default: ""
+
     secrets:
       CODECOV_TOKEN:
         description: "The Codecov token to use for uploading coverage reports."
@@ -76,7 +94,7 @@ jobs:
     name: ${{ inputs.config_name }}
     runs-on: ${{ fromJSON(inputs.runs_on) }}
     container: ${{ inputs.image != '' && inputs.image || null }}
-    timeout-minutes: ${{ inputs.sanitizers != '' && 360 || 60 }}
+    timeout-minutes: ${{ inputs.sanitizers != '' && 360 || 180 }}
     env:
       # Use a namespace to keep the objects separate for each configuration.
       CCACHE_NAMESPACE: ${{ inputs.config_name }}
@@ -94,27 +112,41 @@ jobs:
       # header files are copied into separate directories by CMake, which will
       # otherwise result in cache misses.
       CCACHE_SLOPPINESS: include_file_ctime,include_file_mtime
-      # Determine if coverage and voidstar should be enabled.
+      # Determine if coverage, voidstar and validator-keys should be enabled.
       COVERAGE_ENABLED: ${{ contains(inputs.cmake_args, '-Dcoverage=ON') }}
       VOIDSTAR_ENABLED: ${{ contains(inputs.cmake_args, '-Dvoidstar=ON') }}
+      VALIDATOR_KEYS_ENABLED: ${{ contains(inputs.cmake_args, '-Dvalidator_keys=ON') }}
       SANITIZERS_ENABLED: ${{ inputs.sanitizers != '' }}
+      # The binaries reusable-package.yml consumes. A private repository skips
+      # them except on a tag push, which is what produces its release packages.
+      PACKAGING_ARTIFACTS_ENABLED: ${{ github.event.repository.visibility == 'public' || startsWith(github.ref, 'refs/tags/') }}
     steps:
       - name: Cleanup workspace (macOS and Windows)
         if: ${{ runner.os == 'macOS' || runner.os == 'Windows' }}
         uses: XRPLF/actions/cleanup-workspace@c7d9ce5ebb03c752a354889ecd870cadfc2b1cd4
 
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Prepare runner
-        uses: XRPLF/actions/prepare-runner@90f11ee655d1687824fb8793db770477d52afbab
+        uses: XRPLF/actions/prepare-runner@51af40f99ea91a08c3528ddf16d98132dcc7e63c
         with:
           enable_ccache: ${{ inputs.ccache_enabled }}
 
+      # Before any step that uses a build tool, composite actions included.
+      - name: Setup Nix environment
+        if: ${{ inputs.toolchain == 'nix' }}
+        uses: ./.github/actions/setup-nix-env
+
       - name: Set ccache log file
         if: ${{ inputs.ccache_enabled && runner.debug == '1' }}
         run: echo "CCACHE_LOGFILE=${{ runner.temp }}/ccache.log" >>"${GITHUB_ENV}"
 
+      - name: Check tools
+        env:
+          CHECK_TOOLS_SKIP_CLONE: "1"
+        run: ./bin/check-tools.sh || true
+
       - name: Print build environment
         uses: XRPLF/actions/print-build-env@59dec886e4afb05a1724443af08baccbc045b574
 
@@ -124,7 +156,28 @@ jobs:
         with:
           subtract: ${{ inputs.nproc_subtract }}
 
+      - name: Set compiler environment (Linux)
+        if: ${{ runner.os == 'Linux' }}
+        uses: ./.github/actions/set-compiler-env
+        with:
+          compiler: ${{ inputs.compiler }}
+
+      - name: Use cargo artifacts cache
+        uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          cache-directories: ${{ env.BUILD_DIR }}/corrosion
+          key: ${{ inputs.config_name }}
+          save-if: ${{ github.ref == 'refs/heads/develop' || startsWith(github.ref, 'refs/heads/release') }}
+          # two workspaces here because build artifacts are located in 2 places:
+          # - crates/target when cargo is called directly
+          # - build/cargo when cargo is called by cmake
+          workspaces: |
+            crates
+            crates -> ${{ runner.os == 'Windows' && format('../{0}/x64/{1}/cargo', env.BUILD_DIR, inputs.build_type) || format('../{0}/cargo', env.BUILD_DIR) }}
+
+      # `setup-nix-env` already did this for the Nix toolchain.
       - name: Setup Conan
+        if: ${{ inputs.toolchain != 'nix' }}
         env:
           SANITIZERS: ${{ inputs.sanitizers }}
         uses: ./.github/actions/setup-conan
@@ -146,37 +199,32 @@ jobs:
           CMAKE_ARGS: ${{ inputs.cmake_args }}
         run: |
           cmake \
-              -G '${{ runner.os == 'Windows' && 'Visual Studio 17 2022' || 'Ninja' }}' \
+              -G '${{ runner.os == 'Windows' && 'Visual Studio 18 2026' || 'Ninja' }}' \
               -DCMAKE_TOOLCHAIN_FILE:FILEPATH=build/generators/conan_toolchain.cmake \
               -DCMAKE_BUILD_TYPE="${BUILD_TYPE}" \
               ${CMAKE_ARGS} \
               ..
 
-      - name: Check protocol autogen files are up-to-date
-        working-directory: ${{ env.BUILD_DIR }}
+      # Export the sanitizer options before any instrumented binary runs. The
+      # build step below invokes instrumented dependency tools (protoc, grpc),
+      # so setting UBSAN_OPTIONS here lets the UBSan suppression list silence
+      # their diagnostics too, not just at test time.
+      # GITHUB_WORKSPACE (not the github.workspace context) is used so the path
+      # resolves correctly inside the container job.
+      - name: Set sanitizer options
+        if: ${{ !inputs.build_only && env.SANITIZERS_ENABLED == 'true' }}
         env:
-          MESSAGE: |
-
-            The generated protocol wrapper classes are out of date.
-
-            This typically happens when the macro files or generator scripts
-            have changed but the generated files were not regenerated.
-
-            To fix this:
-              1. Run: cmake --build . --target setup_code_gen
-              2. Run: cmake --build . --target code_gen
-              3. Commit and push the regenerated files
+          CONFIG_NAME: ${{ inputs.config_name }}
         run: |
-          set -e
-          cmake --build . --target setup_code_gen
-          cmake --build . --target code_gen
-          DIFF=$(git -C .. status --porcelain -- include/xrpl/protocol_autogen src/tests/libxrpl/protocol_autogen)
-          if [ -n "${DIFF}" ]; then
-              echo "::error::Generated protocol files are out of date"
-              git -C .. diff -- include/xrpl/protocol_autogen src/tests/libxrpl/protocol_autogen
-              echo "${MESSAGE}"
-              exit 1
+          SUPP="${GITHUB_WORKSPACE}/sanitizers/suppressions"
+          ASAN_OPTS="include=${SUPP}/runtime-asan-options.txt:suppressions=${SUPP}/asan.supp"
+          if [[ "${CONFIG_NAME}" == *gcc* ]]; then
+              ASAN_OPTS="${ASAN_OPTS}:alloc_dealloc_mismatch=0"
           fi
+          echo "ASAN_OPTIONS=${ASAN_OPTS}" >>${GITHUB_ENV}
+          echo "TSAN_OPTIONS=include=${SUPP}/runtime-tsan-options.txt:suppressions=${SUPP}/tsan.supp" >>${GITHUB_ENV}
+          echo "UBSAN_OPTIONS=include=${SUPP}/runtime-ubsan-options.txt:suppressions=${SUPP}/ubsan.supp" >>${GITHUB_ENV}
+          echo "LSAN_OPTIONS=include=${SUPP}/runtime-lsan-options.txt:suppressions=${SUPP}/lsan.supp" >>${GITHUB_ENV}
 
       - name: Build the binary
         working-directory: ${{ env.BUILD_DIR }}
@@ -185,11 +233,31 @@ jobs:
           BUILD_TYPE: ${{ inputs.build_type }}
           CMAKE_TARGET: ${{ inputs.cmake_target }}
         run: |
+          set -o pipefail
           cmake \
               --build . \
               --config "${BUILD_TYPE}" \
               --parallel "${BUILD_NPROC}" \
-              --target "${CMAKE_TARGET}"
+              --target "${CMAKE_TARGET}" \
+              2>&1 | tee "${GITHUB_WORKSPACE}/build.log"
+
+      # Nothing may reference the store, so whole trees are checked - the Conan
+      # cache included, since what it holds is what gets uploaded and reused.
+      - name: Check the build output for Nix store references (Nix toolchain)
+        if: ${{ inputs.toolchain == 'nix' }}
+        run: ./bin/check-nix-store-refs.sh "${BUILD_DIR}"
+
+      - name: Check the Conan cache for Nix store references (Nix toolchain)
+        if: ${{ inputs.toolchain == 'nix' }}
+        run: ./bin/check-nix-store-refs.sh "${CONAN_HOME}"
+
+      # Only what PatchNixBinary.cmake retargets: the toolchain in the Linux
+      # images always references the store. Same condition it uses.
+      - name: Check for Nix store references (Linux)
+        if: ${{ runner.os == 'Linux' && env.SANITIZERS_ENABLED == 'false' }}
+        run: |
+          ./bin/check-nix-store-refs.sh "${BUILD_DIR}/xrpld"
+          ./bin/check-nix-store-refs.sh "${BUILD_DIR}/xrpl_tests"
 
       - name: Show ccache statistics
         if: ${{ inputs.ccache_enabled }}
@@ -201,7 +269,7 @@ jobs:
           fi
 
       - name: Upload the binary (Linux)
-        if: ${{ github.event.repository.visibility == 'public' && runner.os == 'Linux' }}
+        if: ${{ env.PACKAGING_ARTIFACTS_ENABLED == 'true' && runner.os == 'Linux' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: xrpld-${{ inputs.config_name }}
@@ -209,6 +277,31 @@ jobs:
           retention-days: 3
           if-no-files-found: error
 
+      - name: Run the validator-keys tests
+        if: ${{ env.VALIDATOR_KEYS_ENABLED == 'true' }}
+        working-directory: ${{ env.BUILD_DIR }}
+        run: ./validator-keys --unittest
+
+      - name: Upload the validator-keys binary
+        if: ${{ env.PACKAGING_ARTIFACTS_ENABLED == 'true' && env.VALIDATOR_KEYS_ENABLED == 'true' }}
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: validator-keys-${{ inputs.config_name }}
+          path: |
+            ${{ env.BUILD_DIR }}/validator-keys
+            ${{ env.BUILD_DIR }}/validator-keys-LICENSE
+          retention-days: 3
+          if-no-files-found: error
+
+      - name: Upload the test binary (Linux)
+        if: ${{ github.event.repository.visibility == 'public' && runner.os == 'Linux' }}
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: xrpl_tests-${{ inputs.config_name }}
+          path: ${{ env.BUILD_DIR }}/xrpl_tests
+          retention-days: 3
+          if-no-files-found: error
+
       - name: Export server definitions
         if: ${{ runner.os != 'Windows' && !inputs.build_only && env.VOIDSTAR_ENABLED != 'true' }}
         working-directory: ${{ env.BUILD_DIR }}
@@ -217,7 +310,7 @@ jobs:
           ./xrpld --definitions | python3 -m json.tool >server_definitions.json
 
       - name: Upload server definitions
-        if: ${{ github.event.repository.visibility == 'public' && inputs.config_name == 'debian-bookworm-gcc-13-amd64-release' }}
+        if: ${{ github.event.repository.visibility == 'public' && inputs.config_name == 'ubuntu-gcc-debug-amd64-coverage' }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: server-definitions
@@ -243,32 +336,10 @@ jobs:
         run: |
           ./xrpld --version | grep libvoidstar
 
-      - name: Set sanitizer options
-        if: ${{ !inputs.build_only && env.SANITIZERS_ENABLED == 'true' }}
-        env:
-          CONFIG_NAME: ${{ inputs.config_name }}
-        run: |
-          ASAN_OPTS="include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-asan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/asan.supp"
-          if [[ "${CONFIG_NAME}" == *gcc* ]]; then
-              ASAN_OPTS="${ASAN_OPTS}:alloc_dealloc_mismatch=0"
-          fi
-          echo "ASAN_OPTIONS=${ASAN_OPTS}" >>${GITHUB_ENV}
-          echo "TSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-tsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/tsan.supp" >>${GITHUB_ENV}
-          echo "UBSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-ubsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/ubsan.supp" >>${GITHUB_ENV}
-          echo "LSAN_OPTIONS=include=${GITHUB_WORKSPACE}/sanitizers/suppressions/runtime-lsan-options.txt:suppressions=${GITHUB_WORKSPACE}/sanitizers/suppressions/lsan.supp" >>${GITHUB_ENV}
-
       - name: Run the separate tests
         if: ${{ !inputs.build_only }}
-        working-directory: ${{ env.BUILD_DIR }}
-        # Windows locks some of the build files while running tests, and parallel jobs can collide
-        env:
-          BUILD_TYPE: ${{ inputs.build_type }}
-          PARALLELISM: ${{ runner.os == 'Windows' && '1' || steps.nproc.outputs.nproc }}
-        run: |
-          ctest \
-              --output-on-failure \
-              -C "${BUILD_TYPE}" \
-              -j "${PARALLELISM}"
+        working-directory: ${{ runner.os == 'Windows' && format('{0}/{1}', env.BUILD_DIR, inputs.build_type) || env.BUILD_DIR }}
+        run: ./xrpl_tests
 
       - name: Run the embedded tests
         if: ${{ !inputs.build_only }}
@@ -279,27 +350,72 @@ jobs:
           set -o pipefail
           # Coverage builds are slower due to instrumentation; use fewer parallel jobs to avoid flakiness
           [ "$COVERAGE_ENABLED" = "true" ] && BUILD_NPROC=$((BUILD_NPROC - 2))
-          ./xrpld --unittest --unittest-jobs "${BUILD_NPROC}" 2>&1 | tee unittest.log
 
-      - name: Show test failure summary
-        if: ${{ failure() && !inputs.build_only }}
-        env:
-          WORKING_DIR: ${{ runner.os == 'Windows' && format('{0}\{1}', env.BUILD_DIR, inputs.build_type) || env.BUILD_DIR }}
+          # The resolver/preload workaround is only correct for the ASan build:
+          # a regular build doesn't hit the __dn_expand interceptor bug, and must
+          # NOT have libasan injected. So only preload when xrpld is ASan-built.
+          #
+          # libresolv hosts getaddrinfo's resolver helpers (dn_expand, res_*). Under ASan
+          # these are intercepted via dlsym(RTLD_NEXT, ...), which yields a NULL pointer
+          # and crashes DNS resolution if libresolv isn't loaded. Linking it guarantees
+          # the symbols are present; it's a harmless no-op on glibc >= 2.34 (merged into
+          # libc) and is what the compiler driver already does for sanitizer builds.
+          #   https://github.com/llvm/llvm-project/issues/59007
+          #   https://github.com/google/sanitizers/issues/1592
+          if ldd ./xrpld | grep -q libasan; then
+              PRELOAD="$(gcc -print-file-name=libasan.so):/usr/lib/x86_64-linux-gnu/libresolv.so.2"
+          else
+              PRELOAD=""
+          fi
+
+          LD_PRELOAD="$PRELOAD" ./xrpld --unittest --unittest-jobs "${BUILD_NPROC}" 2>&1 | tee "${GITHUB_WORKSPACE}/unittest.log"
+
+      - name: Run Rust tests
+        if: ${{ !inputs.build_only }}
+        working-directory: crates
+        run: cargo nextest run --workspace --all-features --locked --no-tests=warn
+
+      # Smoke-run every benchmark module with a single repetition to confirm the
+      # benchmarks still build and execute. This is a correctness check, not a
+      # performance measurement, so there is nothing to gain from repeating it
+      # across configurations: it is opted into by a single config in the
+      # strategy matrix (see the 'benchmark' flag in the JSON files), which
+      # keeps it off instrumented builds (sanitizers/coverage/voidstar), where
+      # it would be slow and meaningless, off Debug builds, where it is much
+      # slower, and off Windows, where the `install` target does not build them.
+      - name: Run the benchmarks
+        if: ${{ inputs.benchmark }}
+        working-directory: ${{ env.BUILD_DIR }}
         run: |
-          if [ ! -d "${WORKING_DIR}" ]; then
-              echo "Working directory '${WORKING_DIR}' does not exist."
-              exit 0
-          fi
+          rc=0
+          while IFS= read -r bench; do
+              echo "::group::${bench}"
+              "./${bench}" --benchmark_repetitions=1 || rc=1
+              echo "::endgroup::"
+          done < <(find src/benchmarks -type f -perm -u+x -name 'xrpl.bench.*')
+          exit "${rc}"
 
-          cd "${WORKING_DIR}"
+      - name: Show build/test failure summary
+        if: ${{ failure() }}
+        run: |
+          cd "${GITHUB_WORKSPACE}"
 
-          if [ ! -f unittest.log ]; then
-              echo "unittest.log not found; embedded tests may not have run."
-              exit 0
-          fi
-
-          if ! grep -E "failed" unittest.log; then
-              echo "Log present but no failure lines found in unittest.log."
+          if [ -f unittest.log ]; then
+              if ! grep -E "failed" unittest.log | grep -vE "^I[0-9]|^[0-9]+> (ERR:|FTL:)"; then
+                  echo "unittest.log present but no failure lines found."
+              fi
+          elif [ -f build.log ]; then
+              # GCC/Clang emit "error:" (covers "fatal error:"); MSVC emits
+              # "error C####:", "error LNK####:", and "fatal error LNK####:".
+              # -A6 prints the lines that follow each match (source line, caret,
+              # notes, and the "N errors generated" tally) to capture the whole
+              # diagnostic block.
+              if ! grep -E -A6 "error:|error C[0-9]{4}|error LNK[0-9]{4}|fatal error" build.log; then
+                  echo "build.log present but no compile errors found."
+              fi
+          else
+              echo "unittest.log/build.log not found; something went wrong."
+              exit 1
           fi
       - name: Debug failure (Linux)
         if: ${{ failure() && runner.os == 'Linux' && !inputs.build_only }}
@@ -323,13 +439,14 @@ jobs:
               --target coverage
 
       - name: Upload coverage report
-        if: ${{ github.repository == 'XRPLF/rippled' && !inputs.build_only && env.COVERAGE_ENABLED == 'true' }}
+        if: ${{ github.repository_owner == 'XRPLF' && !inputs.build_only && env.COVERAGE_ENABLED == 'true' }}
         uses: codecov/codecov-action@fb8b3582c8e4def4969c97caa2f19720cb33a72f # v7.0.0
         with:
           disable_search: true
           disable_telem: true
           fail_ci_if_error: true
           files: ${{ env.BUILD_DIR }}/coverage.xml
+          flags: cpp
           plugins: noop
           token: ${{ secrets.CODECOV_TOKEN }}
           verbose: true

.github/workflows/reusable-build-test.yml

@@ -19,13 +19,6 @@ on:
         required: true
         type: string
 
-      strategy_matrix:
-        # TODO: Support additional strategies, e.g. "ubuntu" for generating all Ubuntu configurations.
-        description: 'The strategy matrix to use for generating the configurations ("minimal", "all").'
-        required: false
-        type: string
-        default: "minimal"
-
     secrets:
       CODECOV_TOKEN:
         description: "The Codecov token to use for uploading coverage reports."
@@ -37,7 +30,6 @@ jobs:
     uses: ./.github/workflows/reusable-strategy-matrix.yml
     with:
       os: ${{ inputs.os }}
-      strategy_matrix: ${{ inputs.strategy_matrix }}
 
   # Build and test the binary for each configuration.
   build-test-config:
@@ -47,16 +39,18 @@ jobs:
     strategy:
       fail-fast: ${{ github.event_name == 'merge_group' }}
       matrix: ${{ fromJson(needs.generate-matrix.outputs.matrix) }}
-      max-parallel: 10
     with:
+      benchmark: ${{ matrix.benchmark }}
       build_only: ${{ matrix.build_only }}
       build_type: ${{ matrix.build_type }}
       ccache_enabled: ${{ inputs.ccache_enabled }}
       cmake_args: ${{ matrix.cmake_args }}
       cmake_target: ${{ matrix.cmake_target }}
       runs_on: ${{ toJSON(matrix.architecture.runner) }}
-      image: ${{ contains(matrix.architecture.platform, 'linux') && format('ghcr.io/xrplf/ci/{0}-{1}:{2}-{3}-sha-{4}', matrix.os.distro_name, matrix.os.distro_version, matrix.os.compiler_name, matrix.os.compiler_version, matrix.os.image_sha) || '' }}
+      image: ${{ matrix.image || '' }}
       config_name: ${{ matrix.config_name }}
       sanitizers: ${{ matrix.sanitizers }}
+      compiler: ${{ matrix.compiler || '' }}
+      toolchain: ${{ matrix.toolchain || '' }}
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/reusable-check-autogen.yml

@@ -0,0 +1,76 @@
+# This workflow checks that the generated protocol wrapper classes are
+# up-to-date with the macro files and generator scripts they are produced from,
+# see more info in include/xrpl/protocol_autogen/README.md.
+name: Check autogen
+
+# This workflow can only be triggered by other workflows.
+on: workflow_call
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}-autogen
+  cancel-in-progress: true
+
+defaults:
+  run:
+    shell: bash
+
+env:
+  BUILD_DIR: build/codegen
+
+jobs:
+  autogen:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Set up Python
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version: "3.13"
+
+      # Code generation is pure Python, so the standalone project below offers
+      # the same targets as the main build without needing its dependencies or
+      # a compiler, which keeps this job down to a few seconds.
+      - name: Configure CMake
+        run: cmake -S cmake/codegen -B "${BUILD_DIR}"
+
+      - name: Install code generation dependencies
+        run: cmake --build "${BUILD_DIR}" --target setup_code_gen
+
+      - name: Generate code
+        run: cmake --build "${BUILD_DIR}" --target code_gen
+
+      - name: Check for differences
+        env:
+          MESSAGE: |
+
+            The generated protocol wrapper classes are out of date.
+
+            This typically happens when the macro files or generator scripts
+            have changed but the generated files were not regenerated.
+
+            Run the following from the repository root, then commit and push
+            the regenerated files. This needs neither the dependencies nor a
+            compiler. See include/xrpl/protocol_autogen/README.md for more info.
+
+              cmake -S cmake/codegen -B build/codegen
+              cmake --build build/codegen --target setup_code_gen
+              cmake --build build/codegen --target code_gen
+
+            In an already configured build directory, the 'setup_code_gen' and
+            'code_gen' targets do the same thing.
+        run: |
+          # Record untracked files in the index without staging their contents,
+          # so that classes generated for a newly added transaction or ledger
+          # entry type show up in the diff below rather than silently as an
+          # empty one.
+          git add --intent-to-add .
+          DIFF=$(git status --porcelain)
+          if [ -n "${DIFF}" ]; then
+              # Print the differences to give the contributor a hint about what to
+              # expect when running code generation on their own machine.
+              git diff
+              echo "${MESSAGE}"
+              exit 1
+          fi

.github/workflows/reusable-check-levelization.yml

@@ -18,7 +18,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Check levelization
         run: python .github/scripts/levelization/generate.py
       - name: Check for differences

.github/workflows/reusable-check-rename.yml

@@ -18,7 +18,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Check definitions
         run: .github/scripts/rename/definitions.sh .
       - name: Check copyright notices

.github/workflows/reusable-clang-tidy.yml

@@ -3,10 +3,6 @@ name: Run clang-tidy on files
 on:
   workflow_call:
     inputs:
-      check_only_changed:
-        description: "Check only changed files in PR. If false, checks all files in the repository."
-        type: boolean
-        default: false
       create_issue_on_failure:
         description: "Whether to create an issue if the check failed"
         type: boolean
@@ -20,32 +16,34 @@ env:
   BUILD_DIR: build
   BUILD_TYPE: Debug # Debug so that ASSERTS and such participate in clang-tidy check
 
-  OUTPUT_FILE: clang-tidy-output.txt
-  DIFF_FILE: clang-tidy-git-diff.txt
-  ISSUE_FILE: clang-tidy-issue.md
+  OUTPUT_FILE: /tmp/clang-tidy-output.txt
+  FILTERED_OUTPUT_FILE: /tmp/clang-tidy-filtered-output.txt
+  DIFF_FILE: /tmp/clang-tidy-git-diff.txt
+  ISSUE_FILE: /tmp/clang-tidy-issue.md
+
+  COMPILER: clang
 
 jobs:
   determine-files:
-    if: ${{ inputs.check_only_changed }}
     permissions:
       contents: read
-    uses: XRPLF/actions/.github/workflows/determine-tidy-files.yml@224f3c48d3014d082a1129237b8291ff0b0a331f
+    uses: XRPLF/actions/.github/workflows/determine-tidy-files.yml@d041ac9f1fa9f07a4ba335eb4c1c82233fb3fef6
 
   run-clang-tidy:
     name: Run clang tidy
     needs: [determine-files]
-    if: ${{ always() && !cancelled() && (!inputs.check_only_changed || needs.determine-files.outputs.cpp_changed_files != '' || needs.determine-files.outputs.clang_tidy_config_changed == 'true') }}
+    if: ${{ needs.determine-files.outputs.cpp_changed_files != '' || needs.determine-files.outputs.need_full_run == 'true' }}
     runs-on: ["self-hosted", "Linux", "X64", "heavy"]
-    container: "ghcr.io/xrplf/ci/debian-trixie:clang-21-sha-53033a2"
+    container: "ghcr.io/xrplf/xrpld/nix-debian:sha-a0074f8"
     permissions:
       contents: read
       issues: write
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Prepare runner
-        uses: XRPLF/actions/prepare-runner@90f11ee655d1687824fb8793db770477d52afbab
+        uses: XRPLF/actions/prepare-runner@51af40f99ea91a08c3528ddf16d98132dcc7e63c
         with:
           enable_ccache: false
 
@@ -56,6 +54,18 @@ jobs:
         uses: XRPLF/actions/get-nproc@cf0433aa74563aead044a1e395610c96d65a37cf
         id: nproc
 
+      - name: Set compiler environment
+        uses: ./.github/actions/set-compiler-env
+        with:
+          compiler: ${{ env.COMPILER }}
+
+      - name: Use cargo artifacts cache
+        uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          cache-directories: ${{ env.BUILD_DIR }}/corrosion
+          save-if: ${{ github.ref == 'refs/heads/develop' || startsWith(github.ref, 'refs/heads/release') }}
+          workspaces: crates -> ../${{ env.BUILD_DIR }}/cargo
+
       - name: Setup Conan
         uses: ./.github/actions/setup-conan
 
@@ -76,27 +86,28 @@ jobs:
               -Dtests=ON \
               -Dwerr=ON \
               -Dxrpld=ON \
+              -Dverify_headers=ON \
+              -Drust=ON \
               ..
 
-      # clang-tidy needs headers generated from proto files
-      - name: Build libxrpl.libpb
+      - name: Build clang-tidy prerequisites
         working-directory: ${{ env.BUILD_DIR }}
         run: |
-          ninja -j ${{ steps.nproc.outputs.nproc }} xrpl.libpb
+          ninja -j ${{ steps.nproc.outputs.nproc }} tidy_prerequisites
 
       - name: Run clang tidy
         id: run_clang_tidy
         continue-on-error: true
         env:
-          TARGETS: ${{ (needs.determine-files.outputs.clang_tidy_config_changed != 'true' && inputs.check_only_changed) && needs.determine-files.outputs.cpp_changed_files || 'src tests' }}
+          TARGETS: ${{ needs.determine-files.outputs.need_full_run != 'true' && needs.determine-files.outputs.cpp_changed_files || 'include src tests' }}
         run: |
           set -o pipefail
-          run-clang-tidy -j ${{ steps.nproc.outputs.nproc }} -p "${BUILD_DIR}" -quiet -fix -allow-no-checks ${TARGETS} 2>&1 | tee "${OUTPUT_FILE}"
+          run-clang-tidy -j ${{ steps.nproc.outputs.nproc }} -p "${BUILD_DIR}" -quiet -fix -format -allow-no-checks ${TARGETS} 2>&1 | tee "${OUTPUT_FILE}"
 
-      - name: Print errors
+      - name: Print filtered clang-tidy errors
         if: ${{ steps.run_clang_tidy.outcome != 'success' }}
         run: |
-          sed '/error\||/!d' "${OUTPUT_FILE}"
+          bin/filter-clang-tidy.py "${OUTPUT_FILE}"
 
       - name: Upload clang-tidy output
         if: ${{ github.event.repository.visibility == 'public' && steps.run_clang_tidy.outcome != 'success' }}
@@ -140,26 +151,26 @@ jobs:
           \`\`\`
           EOF
 
-      - name: Append clang-tidy output to issue body (filter for errors and warnings)
+      - name: Append filtered clang-tidy output to issue body
         if: ${{ steps.run_clang_tidy.outcome != 'success' }}
         run: |
           if [ -f "${OUTPUT_FILE}" ]; then
-              # Extract lines containing 'error:', 'warning:', or 'note:'
-              grep -E '(error:|warning:|note:)' "${OUTPUT_FILE}" >filtered-output.txt || true
+              # Filter to the unique errors with their source context.
+              bin/filter-clang-tidy.py "${OUTPUT_FILE}" >"${FILTERED_OUTPUT_FILE}" || true
 
               # If filtered output is empty, use original (might be a different error format)
-              if [ ! -s filtered-output.txt ]; then
-                  cp "${OUTPUT_FILE}" filtered-output.txt
+              if [ ! -s "${FILTERED_OUTPUT_FILE}" ]; then
+                  cp "${OUTPUT_FILE}" "${FILTERED_OUTPUT_FILE}"
               fi
 
               # Truncate if too large
-              head -c 60000 filtered-output.txt >>"${ISSUE_FILE}"
-              if [ "$(wc -c <filtered-output.txt)" -gt 60000 ]; then
+              head -c 60000 "${FILTERED_OUTPUT_FILE}" >>"${ISSUE_FILE}"
+              if [ "$(wc -c <"${FILTERED_OUTPUT_FILE}")" -gt 60000 ]; then
                   echo "" >>"${ISSUE_FILE}"
                   echo "... (output truncated, see artifacts for full output)" >>"${ISSUE_FILE}"
               fi
 
-              rm filtered-output.txt
+              rm "${FILTERED_OUTPUT_FILE}"
           else
               echo "No output file found" >>"${ISSUE_FILE}"
           fi

.github/workflows/reusable-package.yml

@@ -1,18 +1,37 @@
-# Build Linux packages (DEB and RPM) from pre-built binary artifacts.
-# Discovers which configurations to package from linux.json (os entries
-# with "package": true) and fans out one job per entry. Today only
-# linux/amd64 is emitted; the architecture is hardcoded both here
-# (runner) and in generate.py.
+# Build Linux packages from the pre-built xrpld and validator-keys artifacts:
+#
+#   - one job per distro, taken from "package_configs" in linux.json
+#   - each job runs in that distro's container, which is what decides DEB or RPM
+#   - with 'publish: true' a job also uploads what it built
+#     (see package/publish_pkg.sh)
+#
+# Only linux/amd64 is supported; the runner is hardcoded in the job below.
 name: Package
 
 on:
   workflow_call:
     inputs:
-      pkg_release:
-        description: "Package release number. Increment when repackaging the same executable."
+      publish:
+        description: "Whether to publish the packages after building them."
+        required: false
+        type: boolean
+        default: false
+      nexus_url:
+        description: "The base URL of the Nexus instance hosting the deb and rpm repositories."
         required: false
         type: string
-        default: "1"
+        default: https://packages.xrplf.org
+
+    secrets:
+      remote_username:
+        description: "The username of a Nexus account with write access to the repositories."
+        required: false
+      remote_password:
+        description: "The password or token for that Nexus account."
+        required: false
+      signing_key:
+        description: "Armoured PGP private key used to sign the RPMs. Required when publishing."
+        required: false
 
 defaults:
   run:
@@ -28,72 +47,83 @@ jobs:
       matrix: ${{ steps.generate.outputs.matrix }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Set up Python
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
-          python-version: 3.13
+          python-version: "3.13"
 
       - name: Generate packaging matrix
         id: generate
         working-directory: .github/scripts/strategy-matrix
-        run: |
-          ./generate.py --packaging --config=linux.json >>"${GITHUB_OUTPUT}"
-
-  generate-version:
-    runs-on: ubuntu-latest
-    outputs:
-      version: ${{ steps.version.outputs.version }}
-    steps:
-      - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-        with:
-          sparse-checkout: |
-            .github/actions/generate-version
-            src/libxrpl/protocol/BuildInfo.cpp
-      - name: Generate version
-        id: version
-        uses: ./.github/actions/generate-version
+        run: ./generate.py --packaging >>"${GITHUB_OUTPUT}"
 
   package:
-    needs: [generate-matrix, generate-version]
-    if: ${{ github.event.repository.visibility == 'public' }}
+    needs: [generate-matrix]
+    if: ${{ github.event.repository.visibility == 'public' || startsWith(github.ref, 'refs/tags/') }}
     strategy:
       fail-fast: false
       matrix: ${{ fromJson(needs.generate-matrix.outputs.matrix) }}
-    name: "${{ matrix.artifact_name }}"
+    name: "${{ matrix.xrpld_artifact_name }}"
     permissions:
       contents: read
     runs-on: ["self-hosted", "Linux", "X64", "heavy"]
-    container: ${{ format('ghcr.io/xrplf/ci/{0}-{1}:{2}-{3}-sha-{4}', matrix.os.distro_name, matrix.os.distro_version, matrix.os.compiler_name, matrix.os.compiler_version, matrix.os.image_sha) }}
+    container: ${{ matrix.image }}
     timeout-minutes: 30
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
-      - name: Download pre-built binary
+      - name: Download pre-built xrpld binary
         uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
         with:
-          name: ${{ matrix.artifact_name }}
+          name: ${{ matrix.xrpld_artifact_name }}
           path: ${{ env.BUILD_DIR }}
 
-      - name: Make binary executable
-        run: chmod +x "${BUILD_DIR}/xrpld"
+      - name: Download pre-built validator-keys binary
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8.0.1
+        with:
+          name: ${{ matrix.validator_keys_artifact_name }}
+          path: ${{ env.BUILD_DIR }}
+
+      - name: Make binaries executable
+        run: chmod +x "${BUILD_DIR}/xrpld" "${BUILD_DIR}/validator-keys"
+
+      - name: Determine release info
+        id: release_info
+        uses: ./.github/actions/release-info
 
       - name: Build package
         env:
-          PKG_VERSION: ${{ needs.generate-version.outputs.version }}
-          PKG_RELEASE: ${{ inputs.pkg_release }}
+          PKG_RELEASE: ${{ steps.release_info.outputs.pkg_release }}
+          PKG_CHANNEL: ${{ steps.release_info.outputs.channel }}
         run: ./package/build_pkg.sh
 
+      # Before the upload, so the artifact and the published package are the
+      # same bytes. DEBs are not signed, so the key is never set on that job.
+      - name: Sign RPM
+        if: ${{ inputs.publish && matrix.distro == 'rhel' }}
+        env:
+          PKG_SIGNING_KEY: ${{ secrets.signing_key }}
+        run: ./package/sign_rpm.sh "${BUILD_DIR}"
+
       - name: Upload package artifact
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
-          name: ${{ matrix.artifact_name }}-pkg-${{ needs.generate-version.outputs.version }}
+          name: ${{ matrix.xrpld_artifact_name }}-pkg
           path: |
             ${{ env.BUILD_DIR }}/debbuild/*.deb
             ${{ env.BUILD_DIR }}/debbuild/*.ddeb
             ${{ env.BUILD_DIR }}/rpmbuild/RPMS/**/*.rpm
           if-no-files-found: error
+
+      - name: Publish package
+        if: ${{ inputs.publish }}
+        env:
+          CHANNEL: ${{ steps.release_info.outputs.channel }}
+          NEXUS_URL: ${{ inputs.nexus_url }}
+          NEXUS_USERNAME: ${{ secrets.remote_username }}
+          NEXUS_PASSWORD: ${{ secrets.remote_password }}
+        run: ./package/publish_pkg.sh "${CHANNEL}" "${BUILD_DIR}"

.github/workflows/reusable-rust.yml

@@ -0,0 +1,86 @@
+# Clippy, coverage and documentation for the Rust crates in crates/. Each runs
+# as an independent job on a GitHub-hosted runner, but inside the same container
+# image used to build the crates in the C++/Corrosion path, so the toolchain
+# (and therefore the lints, coverage instrumentation and the cargo cache) matches
+# what production builds use.
+#
+# Rust unit tests are deliberately NOT run here. They run as part of the C++
+# build (reusable-build-test-config.yml), which already compiles the crates on a
+# self-hosted runner, so there is no need to provision a toolchain again.
+name: Rust
+
+on:
+  workflow_call:
+    secrets:
+      CODECOV_TOKEN:
+        description: "The Codecov token to use for uploading coverage reports."
+        required: true
+
+defaults:
+  run:
+    shell: bash
+    working-directory: crates
+
+permissions:
+  contents: read
+
+jobs:
+  clippy:
+    runs-on: ubuntu-latest
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Use cargo artifacts cache
+        uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          workspaces: crates
+
+      - name: Run clippy
+        run: cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
+
+  coverage:
+    runs-on: ubuntu-latest
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Use cargo artifacts cache
+        uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          workspaces: crates
+
+      - name: Generate coverage report
+        run: cargo llvm-cov nextest --workspace --all-features --locked --no-tests=warn --lcov --output-path lcov.info
+
+      - name: Upload coverage report
+        if: ${{ github.repository == 'XRPLF/rippled' }}
+        uses: codecov/codecov-action@fb8b3582c8e4def4969c97caa2f19720cb33a72f # v7.0.0
+        with:
+          disable_search: true
+          disable_telem: true
+          fail_ci_if_error: true
+          files: crates/lcov.info
+          flags: rust
+          plugins: noop
+          token: ${{ secrets.CODECOV_TOKEN }}
+          verbose: true
+
+  doc:
+    runs-on: ubuntu-latest
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Use cargo artifacts cache
+        uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
+        with:
+          workspaces: crates
+
+      - name: Build documentation
+        env:
+          RUSTDOCFLAGS: "-D warnings"
+        run: cargo doc --workspace --no-deps --all-features --locked

.github/workflows/reusable-strategy-matrix.yml

@@ -4,15 +4,9 @@ on:
   workflow_call:
     inputs:
       os:
-        description: 'The operating system to use for the build ("linux", "macos", "windows").'
+        description: 'The operating system to use for the build ("linux", "macos", "windows", or empty for all).'
         required: false
         type: string
-      strategy_matrix:
-        # TODO: Support additional strategies, e.g. "ubuntu" for generating all Ubuntu configurations.
-        description: 'The strategy matrix to use for generating the configurations ("minimal", "all").'
-        required: false
-        type: string
-        default: "minimal"
     outputs:
       matrix:
         description: "The generated strategy matrix."
@@ -29,17 +23,20 @@ jobs:
       matrix: ${{ steps.generate.outputs.matrix }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Set up Python
-        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
+        uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
         with:
-          python-version: 3.13
+          python-version: "3.13"
 
       - name: Generate strategy matrix
         working-directory: .github/scripts/strategy-matrix
         id: generate
         env:
-          GENERATE_CONFIG: ${{ inputs.os != '' && format('--config={0}.json', inputs.os) || '' }}
-          GENERATE_OPTION: ${{ inputs.strategy_matrix == 'all' && '--all' || '' }}
-        run: ./generate.py ${GENERATE_OPTION} ${GENERATE_CONFIG} >>"${GITHUB_OUTPUT}"
+          GENERATE_CONFIG: ${{ inputs.os != '' && format('--config={0}', inputs.os) || '' }}
+          # Run only the minimal matrix for pull requests that are not yet
+          # labeled "Ready to merge" or "Full CI build". Any other event (merge
+          # queue, push, schedule, manual dispatch) runs the full matrix.
+          GENERATE_MINIMAL: ${{ (github.event_name == 'pull_request' && !contains(github.event.pull_request.labels.*.name, 'Ready to merge') && !contains(github.event.pull_request.labels.*.name, 'Full CI build')) && '--minimal' || '' }}
+        run: ./generate.py ${GENERATE_CONFIG} ${GENERATE_MINIMAL} >>"${GITHUB_OUTPUT}"

.github/workflows/reusable-upload-recipe.yml

@@ -14,7 +14,7 @@ on:
         description: "The URL of the Conan endpoint to use."
         required: false
         type: string
-        default: https://conan.ripplex.io
+        default: https://conan.xrplf.org/repository/conan/
 
     secrets:
       remote_username:
@@ -40,14 +40,18 @@ defaults:
 jobs:
   upload:
     runs-on: ubuntu-latest
-    container: ghcr.io/xrplf/ci/ubuntu-noble:gcc-13-sha-5dd7158
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
+    env:
+      REMOTE_NAME: ${{ inputs.remote_name }}
+      CONAN_LOGIN_USERNAME_XRPLF: ${{ secrets.remote_username }}
+      CONAN_PASSWORD_XRPLF: ${{ secrets.remote_password }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
-      - name: Generate build version number
-        id: version
-        uses: ./.github/actions/generate-version
+      - name: Determine release info
+        id: release_info
+        uses: ./.github/actions/release-info
 
       - name: Set up Conan
         uses: ./.github/actions/setup-conan
@@ -56,25 +60,17 @@ jobs:
           remote_url: ${{ inputs.remote_url }}
 
       - name: Log into Conan remote
-        env:
-          REMOTE_NAME: ${{ inputs.remote_name }}
-          REMOTE_USERNAME: ${{ secrets.remote_username }}
-          REMOTE_PASSWORD: ${{ secrets.remote_password }}
-        run: conan remote login "${REMOTE_NAME}" "${REMOTE_USERNAME}" --password "${REMOTE_PASSWORD}"
+        run: conan remote login "${REMOTE_NAME}" "${CONAN_LOGIN_USERNAME_XRPLF}" --password "${CONAN_PASSWORD_XRPLF}"
 
       - name: Upload Conan recipe (version)
-        env:
-          REMOTE_NAME: ${{ inputs.remote_name }}
         run: |
-          conan export . --version=${{ steps.version.outputs.version }}
-          conan upload --confirm --check --remote="${REMOTE_NAME}" xrpl/${{ steps.version.outputs.version }}
+          conan export . --version=${{ steps.release_info.outputs.version }}
+          conan upload --confirm --check --remote="${REMOTE_NAME}" xrpl/${{ steps.release_info.outputs.version }}
 
       # When this workflow is triggered by a push event, it will always be when merging into the
       # 'develop' branch, see on-trigger.yml.
       - name: Upload Conan recipe (develop)
         if: ${{ github.event_name == 'push' }}
-        env:
-          REMOTE_NAME: ${{ inputs.remote_name }}
         run: |
           conan export . --version=develop
           conan upload --confirm --check --remote="${REMOTE_NAME}" xrpl/develop
@@ -83,8 +79,6 @@ jobs:
       # one of the 'release' branches, see on-pr.yml.
       - name: Upload Conan recipe (rc)
         if: ${{ github.event_name == 'pull_request' }}
-        env:
-          REMOTE_NAME: ${{ inputs.remote_name }}
         run: |
           conan export . --version=rc
           conan upload --confirm --check --remote="${REMOTE_NAME}" xrpl/rc
@@ -93,11 +87,9 @@ jobs:
       # release, see on-tag.yml.
       - name: Upload Conan recipe (release)
         if: ${{ startsWith(github.ref, 'refs/tags/') }}
-        env:
-          REMOTE_NAME: ${{ inputs.remote_name }}
         run: |
           conan export . --version=release
           conan upload --confirm --check --remote="${REMOTE_NAME}" xrpl/release
 
     outputs:
-      ref: xrpl/${{ steps.version.outputs.version }}
+      ref: xrpl/${{ steps.release_info.outputs.version }}

.github/workflows/upload-conan-deps.yml

@@ -30,10 +30,11 @@ on:
       - ".github/scripts/strategy-matrix/**"
       - conanfile.py
       - conan.lock
+      - conan/profiles/**
 
 env:
   CONAN_REMOTE_NAME: xrplf
-  CONAN_REMOTE_URL: https://conan.ripplex.io
+  CONAN_REMOTE_URL: https://conan.xrplf.org/repository/conan/
   NPROC_SUBTRACT: 2
 
 concurrency:
@@ -48,8 +49,6 @@ jobs:
   # Generate the strategy matrix to be used by the following job.
   generate-matrix:
     uses: ./.github/workflows/reusable-strategy-matrix.yml
-    with:
-      strategy_matrix: ${{ github.event_name == 'pull_request' && 'minimal' || 'all' }}
 
   # Build and upload the dependencies for each configuration.
   run-upload-conan-deps:
@@ -58,22 +57,26 @@ jobs:
     strategy:
       fail-fast: false
       matrix: ${{ fromJson(needs.generate-matrix.outputs.matrix) }}
-      max-parallel: 10
     runs-on: ${{ matrix.architecture.runner }}
-    container: ${{ contains(matrix.architecture.platform, 'linux') && format('ghcr.io/xrplf/ci/{0}-{1}:{2}-{3}-sha-{4}', matrix.os.distro_name, matrix.os.distro_version, matrix.os.compiler_name, matrix.os.compiler_version, matrix.os.image_sha) || null }}
+    container: ${{ matrix.image || null }}
     steps:
       - name: Cleanup workspace (macOS and Windows)
         if: ${{ runner.os == 'macOS' || runner.os == 'Windows' }}
         uses: XRPLF/actions/cleanup-workspace@c7d9ce5ebb03c752a354889ecd870cadfc2b1cd4
 
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
       - name: Prepare runner
-        uses: XRPLF/actions/prepare-runner@90f11ee655d1687824fb8793db770477d52afbab
+        uses: XRPLF/actions/prepare-runner@c00c22ada3bd6bcda48fcb0d62fbbab49fec8a0f
         with:
           enable_ccache: false
 
+      # Before any step that uses a build tool, composite actions included.
+      - name: Setup Nix environment
+        if: ${{ matrix.toolchain == 'nix' }}
+        uses: ./.github/actions/setup-nix-env
+
       - name: Print build environment
         uses: XRPLF/actions/print-build-env@59dec886e4afb05a1724443af08baccbc045b574
 
@@ -83,7 +86,15 @@ jobs:
         with:
           subtract: ${{ env.NPROC_SUBTRACT }}
 
+      - name: Set compiler environment (Linux)
+        if: ${{ runner.os == 'Linux' }}
+        uses: ./.github/actions/set-compiler-env
+        with:
+          compiler: ${{ matrix.compiler }}
+
+      # `setup-nix-env` already did this for the Nix toolchain.
       - name: Setup Conan
+        if: ${{ matrix.toolchain != 'nix' }}
         env:
           SANITIZERS: ${{ matrix.sanitizers }}
         uses: ./.github/actions/setup-conan
@@ -102,12 +113,18 @@ jobs:
           log_verbosity: ${{ runner.os == 'Windows' && 'quiet' || 'verbose' }}
           sanitizers: ${{ matrix.sanitizers }}
 
+      - name: Check the Conan cache for Nix store references (Nix toolchain)
+        if: ${{ matrix.toolchain == 'nix' }}
+        run: ./bin/check-nix-store-refs.sh "${CONAN_HOME}"
+
       - name: Log into Conan remote
         if: ${{ github.repository == 'XRPLF/rippled' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') }}
-        run: conan remote login "${CONAN_REMOTE_NAME}" "${{ secrets.CONAN_REMOTE_USERNAME }}" --password "${{ secrets.CONAN_REMOTE_PASSWORD }}"
+        run: conan remote login "${CONAN_REMOTE_NAME}" "${{ secrets.NEXUS_REMOTE_USERNAME }}" --password "${{ secrets.NEXUS_REMOTE_PASSWORD }}"
 
       - name: Upload Conan packages
         if: ${{ github.repository == 'XRPLF/rippled' && (github.event_name == 'push' || github.event_name == 'workflow_dispatch') }}
         env:
           FORCE_OPTION: ${{ github.event.inputs.force_upload == 'true' && '--force' || '' }}
+          CONAN_LOGIN_USERNAME_XRPLF: ${{ secrets.NEXUS_REMOTE_USERNAME }}
+          CONAN_PASSWORD_XRPLF: ${{ secrets.NEXUS_REMOTE_PASSWORD }}
         run: conan upload "*" --remote="${CONAN_REMOTE_NAME}" --confirm ${FORCE_OPTION}

.gitignore

@@ -81,8 +81,14 @@ DerivedData
 # Python
 __pycache__
 
+# Rust build artifacts.
+target/
+
 # Direnv's directory
 /.direnv
 
 # clangd cache
 /.cache
+
+# Rust build directory
+crates/target

.pre-commit-config.yaml

@@ -15,6 +15,7 @@ repos:
     hooks:
       - id: check-added-large-files
         args: [--maxkb=400, --enforce-all]
+      - id: check-executables-have-shebangs
       - id: trailing-whitespace
       - id: end-of-file-fixer
       - id: check-merge-conflict
@@ -27,30 +28,56 @@ repos:
         entry: ./bin/pre-commit/clang_tidy_check.py
         language: python
         types_or: [c++, c]
-        exclude: ^include/xrpl/protocol_autogen
-        pass_filenames: false # script determines the staged files itself
+        # .ipp fragments are included by their owning header rather than compiled
+        # as standalone translation units, so they have no compile_commands.json
+        # entry to lint (verify_headers checks them transitively).
+        exclude: '^include/xrpl/protocol_autogen|\.ipp$'
+        # run-clang-tidy --fix may edit headers included by files it is not run on,
+        # so pre-commit must not split the files across parallel hook invocations.
+        # The script determines the staged files itself and lets run-clang-tidy
+        # handle parallelism internally.
+        pass_filenames: false
       - id: fix-include-style
         name: fix include style
         entry: ./bin/pre-commit/fix_include_style.py
         language: python
         types_or: [c++, c]
         exclude: ^include/xrpl/protocol_autogen/(transactions|ledger_entries)/
+      - id: fix-pragma-once
+        name: fix missing '#pragma once' declarations in header files
+        language: python
+        entry: ./bin/pre-commit/fix_pragma_once.py
+        files: \.(h|hpp)$
+      - id: check-doxygen-style
+        name: check Doxygen comment style
+        entry: ./bin/pre-commit/check_doxygen_style.py
+        language: python
+        types_or: [c++, c]
 
   - repo: https://github.com/pre-commit/mirrors-clang-format
-    rev: dd18dad857d6133e90bbe478f4f2f22ec0030269 # frozen: v22.1.5
+    rev: f4d7745e17a28aad7eed2f4874ca8d1568c11c4c # frozen: v22.1.8
     hooks:
       - id: clang-format
         args: [--style=file]
-        "types_or": [c++, c, proto]
+        types_or: [c++, c, proto]
         exclude: ^include/xrpl/protocol_autogen/(transactions|ledger_entries)/
 
+  - repo: local
+    hooks:
+      - id: cargo-fmt
+        name: cargo fmt
+        entry: cargo fmt --manifest-path crates/Cargo.toml --all
+        language: system
+        types: [rust]
+        pass_filenames: false # rustfmt formats the whole workspace
+
   - repo: https://github.com/BlankSpruce/gersemi-pre-commit
-    rev: faadd6a9d852369ca94f4d15b2404c967ba8cb01 # frozen: 0.27.6
+    rev: e98930bdc210d3387007f9252d8c1694ea7e410f # frozen: 0.27.7
     hooks:
       - id: gersemi
 
   - repo: https://github.com/rbubley/mirrors-prettier
-    rev: 515f543f5718ebfd6ce22e16708bb32c68ff96e1 # frozen: v3.8.3
+    rev: 9337a74165b178ae2c766f60bee7252a0f06f3e8 # frozen: v3.9.5
     hooks:
       - id: prettier
         args: [--end-of-line=auto]
@@ -80,22 +107,21 @@ repos:
         files: \.md$
 
   - repo: https://github.com/streetsidesoftware/cspell-cli
-    rev: 4643f154907327ee0a2c7038f0296e0dd77d9776 # frozen: v10.0.0
+    rev: ea11f9efc0bec520073405bc30552da887ba71bc # frozen: v10.0.1
     hooks:
-      - id: cspell # Spell check changed files
+      - id: cspell
+        name: check changed files spelling
         exclude: |
           (?x)^(
-              .config/cspell.config.yaml|
+              \.cspell\.config\.yaml|
               include/xrpl/protocol_autogen/(transactions|ledger_entries)/.*
           )$
-      - id: cspell # Spell check the commit message
+      - id: cspell
         name: check commit message spelling
         args:
           - --no-must-find-files
           - --no-progress
           - --no-summary
-          - --files
-          - .git/COMMIT_EDITMSG
         stages: [commit-msg]
 
   - repo: local

API-CHANGELOG.md

@@ -28,6 +28,9 @@ This section contains changes targeting a future version.
 
 ### Additions
 
+- `account_tx`: Added an optional `delegate` request object to filter delegated transactions. The object requires `delegate_filter`, which must be either `actor` for transactions owned by the requested account but signed by another account, or `authorizer` for transactions signed by the requested account on behalf of another account. The optional `counter_party` account narrows the results to a specific signer/delegate for `actor` or a specific owner/delegator for `authorizer`. Malformed `delegate`, `delegate_filter`, and `counter_party` values return standard invalid field errors, and invalid account IDs return `actMalformed`.
+  When paginating delegate-filtered queries, a marker from a delegate-filtered query includes a `delegate` flag and is only valid for follow-up requests that also supply `delegate` (mixing marker conventions returns `invalidParams`). Because filtering is applied after the ledger scan, a page may contain fewer results than `limit` (possibly zero) while still returning a marker, so callers must continue until no marker is present.
+
 - `ledger_entry`, `account_objects`: The `Delegate` ledger entry now includes an optional `DestinationNode` field, which stores the index into the authorized account's owner directory. This field is present on entries created after bidirectional directory tracking was introduced and may appear in RPC responses for those entries. ([#6681](https://github.com/XRPLF/rippled/pull/6681))
 
 - `server_definitions`: Added the following new sections to the response ([#6321](https://github.com/XRPLF/rippled/pull/6321)):
@@ -39,6 +42,7 @@ This section contains changes targeting a future version.
 
 ### Bugfixes
 
+- `get_aggregate_price`: Duplicate entries in the `oracles` request array are now ignored. [#6586](https://github.com/XRPLF/rippled/pull/6586)
 - Peer Crawler: The `port` field in `overlay.active[]` now consistently returns an integer instead of a string for outbound peers. [#6318](https://github.com/XRPLF/rippled/pull/6318)
 - `ping`: The `ip` field is no longer returned as an empty string for proxied connections without a forwarded-for header. It is now omitted, consistent with the behavior for identified connections. [#6730](https://github.com/XRPLF/rippled/pull/6730)
 - gRPC `GetLedgerDiff`: Fixed error message that incorrectly said "base ledger not validated" when the desired ledger was not validated. [#6730](https://github.com/XRPLF/rippled/pull/6730)
@@ -50,6 +54,8 @@ This section contains changes targeting a future version.
 - `submit`: The `fail_hard` field now returns an error if the value is not a boolean. [#6529](https://github.com/XRPLF/rippled/pull/6529)
 - `subscribe`: The `taker` field in the `books` array now returns `actMalformed` instead of `badIssuer` if the value is not a valid account. [#6529](https://github.com/XRPLF/rippled/pull/6529)
 - Fixed a bug in `Forwarded` HTTP header parsing where the extracted IP address could be incorrect when no comma or semicolon delimiter follows the address. This could cause the server to misidentify a client's IP address when operating behind a reverse proxy. [#6529](https://github.com/XRPLF/rippled/pull/6529)
+- `gateway_balances`: The `account` and `ident` fields now return an `invalidParams` error if the value is not a string, instead of an `internal` error. [#7655](https://github.com/XRPLF/rippled/pull/7655)
+- `account_lines`: The `peer` field now returns an error if the value is not a string. [#7728](https://github.com/XRPLF/rippled/pull/7728)
 
 ## XRP Ledger server version 3.1.0
 

BUILD.md

@@ -1,26 +1,38 @@
-| :warning: **WARNING** :warning:                                                                                                                                                                                                |
-| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
-| These instructions assume you have a C++ development environment ready with Git, Python, Conan, CMake, and a C++ compiler. For help setting one up on Linux, macOS, or Windows, [see this guide](./docs/build/environment.md). |
+| :warning: **WARNING** :warning:                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| These instructions assume you have a C++ development environment ready with Git, Python, Conan, CMake, and a C++ compiler. For help setting one up on Linux, macOS, or Windows, [see this guide](./docs/build/environment.md).<br><br>These instructions also assume a basic familiarity with Conan and CMake. If you are unfamiliar with Conan, you can read our [crash course](./docs/build/conan.md) or the official [Getting Started][conan-getting-started] walkthrough. |
 
-> These instructions also assume a basic familiarity with Conan and CMake.
-> If you are unfamiliar with Conan, you can read our
-> [crash course](./docs/build/conan.md) or the official [Getting Started][3]
-> walkthrough.
+## Minimum Requirements
 
-## Branches
+For the hardware needed to run a node, see
+[System Requirements](https://xrpl.org/system-requirements.html).
 
-For a stable release, choose the `master` branch or one of the [tagged
-releases](https://github.com/XRPLF/rippled/releases).
+For the software needed to build xrpld, see the
+[environment setup guide](./docs/build/environment.md).
 
-```bash
-git checkout master
-```
+## Operating Systems
 
-For the latest release candidate, choose the `release` branch.
+### Linux
 
-```bash
-git checkout release
-```
+The Ubuntu Linux distribution has received the highest level of quality
+assurance, testing, and support. We also support Red Hat and use Debian
+internally.
+Our Linux CI tooling is distro-independent and uses a Nix-based environment, so it should be possible to build on other Linux distributions as well, although we have not tested them.
+
+### macOS
+
+Many `xrpld` engineers use macOS for development.
+The minimum supported version is macOS 15 (Sequoia).
+CI testing is done in macOS 26 (Tahoe), but the build defaults `CMAKE_OSX_DEPLOYMENT_TARGET` to 15.
+
+### Windows
+
+Windows is used by some engineers for development only, and is not recommended
+for production use.
+
+## Steps
+
+### Branches
 
 For the latest set of untested features, or to contribute, choose the `develop`
 branch.
@@ -29,303 +41,37 @@ branch.
 git checkout develop
 ```
 
-## Minimum Requirements
+For a release candidate, choose the relevant release branch, e.g.
+`release/3.2.x`.
 
-See [System Requirements](https://xrpl.org/system-requirements.html).
+```bash
+git checkout release/3.2.x
+```
 
-Building xrpld generally requires git, Python, Conan, CMake, and a C++
-compiler. Some guidance on setting up such a [C++ development environment can be
-found here](./docs/build/environment.md).
-
-- [Python 3.11](https://www.python.org/downloads/), or higher
-- [Conan 2.17](https://conan.io/downloads.html)[^1], or higher
-- [CMake 3.22](https://cmake.org/download/), or higher
-
-[^1]:
-    It is possible to build with Conan 1.60+, but the instructions are
-    significantly different, which is why we are not recommending it.
-
-`xrpld` is written in the C++20 dialect and includes the `<concepts>` header.
-The [minimum compiler versions][2] required are:
-
-| Compiler    | Version   |
-| ----------- | --------- |
-| GCC         | 12        |
-| Clang       | 16        |
-| Apple Clang | 16        |
-| MSVC        | 19.44[^3] |
-
-### Linux
-
-The Ubuntu Linux distribution has received the highest level of quality
-assurance, testing, and support. We also support Red Hat and use Debian
-internally.
-
-Here are [sample instructions for setting up a C++ development environment on
-Linux](./docs/build/environment.md#linux).
-
-### Mac
-
-Many xrpld engineers use macOS for development.
-
-Here are [sample instructions for setting up a C++ development environment on
-macOS](./docs/build/environment.md#macos).
-
-### Windows
-
-Windows is used by some engineers for development only.
-
-[^3]: Windows is not recommended for production use.
-
-## Steps
+For a stable release, choose one of the [tagged
+releases](https://github.com/XRPLF/rippled/releases).
 
 ### Set Up Conan
 
-After you have a [C++ development environment](./docs/build/environment.md) ready with Git, Python,
-Conan, CMake, and a C++ compiler, you may need to set up your Conan profile.
-
-These instructions assume a basic familiarity with Conan and CMake. If you are
-unfamiliar with Conan, then please read [this crash course](./docs/build/conan.md) or the official
-[Getting Started][3] walkthrough.
-
-#### Conan lockfile
-
-To achieve reproducible dependencies, we use a [Conan lockfile](https://docs.conan.io/2/tutorial/versioning/lockfiles.html),
-which has to be updated every time dependencies change.
-
-Please see the [instructions on how to regenerate the lockfile](conan/lockfile/README.md).
-
-#### Default profile
-
-We recommend that you import the provided `conan/profiles/default` profile:
+Once your [development environment](./docs/build/environment.md) is ready, set
+Conan up for this repository:
 
 ```bash
-conan config install conan/profiles/ -tf $(conan config home)/profiles/
+./conan/init.sh
 ```
 
-You can check your Conan profile by running:
+That installs our [`global.conf`](./conan/global.conf), our Conan
+[profiles](./conan/profiles), and the `xrplf` remote that hosts some of our
+dependencies. It honours `CONAN_HOME` and never deletes an existing Conan home,
+so it is safe to re-run — it only overwrites the files it manages.
 
-```bash
-conan profile show
-```
+> [!TIP]
+> In the [Nix development shell](./docs/build/nix.md#conan-configuration) this is
+> already done for you: the script runs on entry.
 
-#### Custom profile
-
-If the default profile does not work for you and you do not yet have a Conan
-profile, you can create one by running:
-
-```bash
-conan profile detect
-```
-
-You may need to make changes to the profile to suit your environment. You can
-refer to the provided `conan/profiles/default` profile for inspiration, and you
-may also need to apply the required [tweaks](#conan-profile-tweaks) to this
-default profile.
-
-### Patched recipes
-
-Occasionally, we need patched recipes or recipes not present in Conan Center.
-We maintain a fork of the Conan Center Index
-[here](https://github.com/XRPLF/conan-center-index/) containing the modified and newly added recipes.
-
-To ensure our patched recipes are used, you must add our Conan remote at a
-higher index than the default Conan Center remote, so it is consulted first. You
-can do this by running:
-
-```bash
-conan remote add --index 0 xrplf https://conan.ripplex.io
-```
-
-Alternatively, you can pull our recipes from the repository and export them locally:
-
-```bash
-# Define which recipes to export.
-recipes=('abseil' 'ed25519' 'mpt-crypto' 'openssl' 'secp256k1' 'snappy' 'soci' 'wasm-xrplf' 'wasmi')
-
-# Selectively check out the recipes from our CCI fork.
-cd external
-mkdir -p conan-center-index
-cd conan-center-index
-git init
-git remote add origin git@github.com:XRPLF/conan-center-index.git
-git sparse-checkout init
-for recipe in "${recipes[@]}"; do
-    echo "Checking out recipe '${recipe}'..."
-    git sparse-checkout add recipes/${recipe}
-done
-git fetch origin master
-git checkout master
-
-./export_all.sh
-cd ../../
-```
-
-In the case we switch to a newer version of a dependency that still requires a
-patch or add a new dependency, it will be necessary for you to pull in the changes and re-export the
-updated dependencies with the newer version. However, if we switch to a newer
-version that no longer requires a patch, no action is required on your part, as
-the new recipe will be automatically pulled from the official Conan Center.
-
-> [!NOTE]
-> You might need to add `--lockfile=""` to your `conan install` command
-> to avoid automatic use of the existing `conan.lock` file when you run
-> `conan export` manually on your machine
->
-> This is not recommended though, as you might end up using different revisions of recipes.
-
-### Conan profile tweaks
-
-#### Missing compiler version
-
-If you see an error similar to the following after running `conan profile show`:
-
-```text
-ERROR: Invalid setting '17' is not a valid 'settings.compiler.version' value.
-Possible values are ['5.0', '5.1', '6.0', '6.1', '7.0', '7.3', '8.0', '8.1',
-'9.0', '9.1', '10.0', '11.0', '12.0', '13', '13.0', '13.1', '14', '14.0', '15',
-'15.0', '16', '16.0']
-Read "http://docs.conan.io/2/knowledge/faq.html#error-invalid-setting"
-```
-
-you need to add your compiler to the list of compiler versions in
-`$(conan config home)/settings_user.yml`, by adding the required version number(s)
-to the `version` array specific for your compiler. For example:
-
-```yaml
-compiler:
-  apple-clang:
-    version: ["17.0"]
-```
-
-#### Multiple compilers
-
-If you have multiple compilers installed, make sure to select the one to use in
-your default Conan configuration **before** running `conan profile detect`, by
-setting the `CC` and `CXX` environment variables.
-
-For example, if you are running MacOS and have [homebrew
-LLVM@18](https://formulae.brew.sh/formula/llvm@18), and want to use it as a
-compiler in the new Conan profile:
-
-```bash
-export CC=$(brew --prefix llvm@18)/bin/clang
-export CXX=$(brew --prefix llvm@18)/bin/clang++
-conan profile detect
-```
-
-You should also explicitly set the path to the compiler in the profile file,
-which helps to avoid errors when `CC` and/or `CXX` are set and disagree with the
-selected Conan profile. For example:
-
-```text
-[conf]
-tools.build:compiler_executables={'c':'/usr/bin/gcc','cpp':'/usr/bin/g++'}
-```
-
-#### Multiple profiles
-
-You can manage multiple Conan profiles in the directory
-`$(conan config home)/profiles`, for example renaming `default` to a different
-name and then creating a new `default` profile for a different compiler.
-
-#### Select language
-
-The default profile created by Conan will typically select different C++ dialect
-than C++20 used by this project. You should set `20` in the profile line
-starting with `compiler.cppstd=`. For example:
-
-```bash
-sed -i.bak -e 's|^compiler\.cppstd=.*$|compiler.cppstd=20|' $(conan config home)/profiles/default
-```
-
-#### Select standard library in Linux
-
-**Linux** developers will commonly have a default Conan [profile][] that
-compiles with GCC and links with libstdc++. If you are linking with libstdc++
-(see profile setting `compiler.libcxx`), then you will need to choose the
-`libstdc++11` ABI:
-
-```bash
-sed -i.bak -e 's|^compiler\.libcxx=.*$|compiler.libcxx=libstdc++11|' $(conan config home)/profiles/default
-```
-
-#### Select architecture and runtime in Windows
-
-**Windows** developers may need to use the x64 native build tools. An easy way
-to do that is to run the shortcut "x64 Native Tools Command Prompt" for the
-version of Visual Studio that you have installed.
-
-Windows developers must also build `xrpld` and its dependencies for the x64
-architecture:
-
-```bash
-sed -i.bak -e 's|^arch=.*$|arch=x86_64|' $(conan config home)/profiles/default
-```
-
-**Windows** developers also must select static runtime:
-
-```bash
-sed -i.bak -e 's|^compiler\.runtime=.*$|compiler.runtime=static|' $(conan config home)/profiles/default
-```
-
-#### Clang workaround for grpc
-
-If your compiler is clang, version 19 or later, or apple-clang, version 17 or
-later, you may encounter a compilation error while building the `grpc`
-dependency:
-
-```text
-In file included from .../lib/promise/try_seq.h:26:
-.../lib/promise/detail/basic_seq.h:499:38: error: a template argument list is expected after a name prefixed by the template keyword [-Wmissing-template-arg-list-after-template-kw]
-  499 |                     Traits::template CallSeqFactory(f_, *cur_, std::move(arg)));
-      |                                      ^
-```
-
-The workaround for this error is to add two lines to profile:
-
-```text
-[conf]
-tools.build:cxxflags=['-Wno-missing-template-arg-list-after-template-kw']
-```
-
-#### Workaround for gcc 12
-
-If your compiler is gcc, version 12, and you have enabled `werr` option, you may
-encounter a compilation error such as:
-
-```text
-/usr/include/c++/12/bits/char_traits.h:435:56: error: 'void* __builtin_memcpy(void*, const void*, long unsigned int)' accessing 9223372036854775810 or more bytes at offsets [2, 9223372036854775807] and 1 may overlap up to 9223372036854775813 bytes at offset -3 [-Werror=restrict]
-  435 |         return static_cast<char_type*>(__builtin_memcpy(__s1, __s2, __n));
-      |                                        ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
-cc1plus: all warnings being treated as errors
-```
-
-The workaround for this error is to add two lines to your profile:
-
-```text
-[conf]
-tools.build:cxxflags=['-Wno-restrict']
-```
-
-#### Workaround for clang 16
-
-If your compiler is clang, version 16, you may encounter compilation error such
-as:
-
-```text
-In file included from .../boost/beast/websocket/stream.hpp:2857:
-.../boost/beast/websocket/impl/read.hpp:695:17: error: call to 'async_teardown' is ambiguous
-                async_teardown(impl.role, impl.stream(),
-                ^~~~~~~~~~~~~~
-```
-
-The workaround for this error is to add two lines to your profile:
-
-```text
-[conf]
-tools.build:cxxflags=['-DBOOST_ASIO_DISABLE_CONCEPTS']
-```
+You can inspect the resulting profile with `conan profile show`. If it is not
+suitable for your environment, create a custom profile and pass it to Conan — see
+[Advanced Conan configuration](./docs/build/advanced_conan.md).
 
 ### Set Up Ccache
 
@@ -333,14 +79,7 @@ To speed up repeated compilations, we recommend that you install
 [ccache](https://ccache.dev), a tool that wraps your compiler so that it can
 cache build objects locally.
 
-#### Linux
-
-You can install it using the package manager, e.g. `sudo apt install ccache`
-(Ubuntu) or `sudo dnf install ccache` (RHEL).
-
-#### macOS
-
-You can install it using Homebrew, i.e. `brew install ccache`.
+On Linux and macOS, `ccache` is included in the [Nix development shell](./docs/build/nix.md).
 
 #### Windows
 
@@ -475,7 +214,17 @@ cmake --build . --target setup_code_gen  # create venv and install dependencies
 cmake --build . --target code_gen        # regenerate code
 ```
 
-The regenerated files should be committed alongside your changes.
+The same targets are also available as a standalone project, which does not
+need the dependencies to be configured first:
+
+```
+cmake -S cmake/codegen -B build/codegen
+cmake --build build/codegen --target setup_code_gen
+cmake --build build/codegen --target code_gen
+```
+
+The regenerated files should be committed alongside your changes. CI verifies
+that they are up-to-date.
 
 ## Coverage report
 
@@ -487,10 +236,14 @@ which is only enabled when the `coverage` option is set, e.g. with
 Prerequisites for the coverage report:
 
 - [gcovr tool][gcovr] (can be installed e.g. with [pip][python-pip])
-- `gcov` for GCC (installed with the compiler by default) or
-- `llvm-cov` for Clang (installed with the compiler by default)
+- `gcov` for GCC or `llvm-cov` for Clang, usually installed with the compiler
 - `Debug` build type
 
+> [!NOTE]
+> Clang coverage is not available in the [Nix development shell](./docs/build/nix.md#building-xrpld-in-the-nix-shell):
+> its `clang` shells do not ship `llvm-cov`. Use a `gcc` shell instead (`.#gcc`,
+> or `.#gcc-plain` on Linux), which provides a `gcov` matching its compiler.
+
 A coverage report is created when the following steps are completed, in order:
 
 1. `xrpld` binary built with instrumentation data, enabled by the `coverage`
@@ -547,21 +300,66 @@ See [Sanitizers docs](./docs/build/sanitizers.md) for more details.
 
 ## Options
 
-| Option     | Default Value | Description                                                    |
-| ---------- | ------------- | -------------------------------------------------------------- |
-| `assert`   | OFF           | Enable assertions.                                             |
-| `coverage` | OFF           | Prepare the coverage report.                                   |
-| `tests`    | OFF           | Build tests.                                                   |
-| `unity`    | OFF           | Configure a unity build.                                       |
-| `xrpld`    | OFF           | Build the xrpld application, and not just the libxrpl library. |
-| `werr`     | OFF           | Treat compilation warnings as errors                           |
-| `wextra`   | OFF           | Enable additional compilation warnings                         |
+| Option           | Default Value | Description                                                                   |
+| ---------------- | ------------- | ----------------------------------------------------------------------------- |
+| `assert`         | OFF           | Force enabling assertions.                                                    |
+| `coverage`       | OFF           | Prepare the coverage report.                                                  |
+| `rust`           | OFF           | Build the Rust crates and the C++ code that depends on them.                  |
+| `tests`          | OFF           | Build tests.                                                                  |
+| `unity`          | OFF           | Configure a unity build.                                                      |
+| `verify_headers` | ON            | Make the `verify-headers` target available to compile each header on its own. |
+| `xrpld`          | OFF           | Build the xrpld application, and not just the libxrpl library.                |
+| `werr`           | OFF           | Treat compilation warnings as errors                                          |
+| `wextra`         | OFF           | Enable additional compilation warnings                                        |
 
-[Unity builds][5] may be faster for the first build (at the cost of much more
+[Unity builds][unity-build] may be faster for the first build (at the cost of much more
 memory) since they concatenate sources into fewer translation units. Non-unity
 builds may be faster for incremental builds, and can be helpful for detecting
 `#include` omissions.
 
+### Rust crates
+
+The Rust crates in `crates/` are only part of the build when `rust` is ON. With
+`-Drust=OFF` (the default) the `crates` directory is not added to the build, no
+cxxbridge bindings are generated, and the C++ tests that exercise the Rust
+interop are not compiled — so no Rust toolchain is needed. CI builds always pass
+`-Drust=ON`.
+
+With `-Drust=ON` you need one extra dependency: a Rust toolchain (`cargo`,
+`rustc`) matching the channel pinned in
+[`rust-toolchain.toml`](./rust-toolchain.toml), which compiles the crates and
+generates the cxxbridge bindings. It is provided by the
+[Nix development shell](./docs/build/nix.md), so `-Drust=ON` works there without
+any extra setup; otherwise install it as described in
+[Rust](./docs/build/environment.md#rust).
+
+The crates also have their own Rust unit tests. Those are run with `cargo` and
+need only the Rust toolchain, independently of CMake and of the `rust` option
+(CI runs them with `cargo nextest`):
+
+```bash
+cargo test --manifest-path crates/Cargo.toml --workspace
+```
+
+### Verifying headers
+
+The regular build only compiles `.cpp` files, so a header is only ever checked
+through whatever translation unit happens to include it. A header that forgets
+an `#include` is not caught as long as every `.cpp` that uses it includes its
+missing dependency first. The `verify_headers` option (ON by default) adds a
+`verify-headers` target that compiles every header on its own, which fails if a
+header is not self-contained:
+
+```bash
+cmake --build . --target verify-headers
+```
+
+The per-header objects are excluded from the `all` target, so a normal build
+never compiles them; they are built only through `verify-headers`. The generated
+translation units do appear in `compile_commands.json`, so clang-tidy (and
+clangd and IDEs) can lint each header on its own. Pass `-Dverify_headers=OFF` to
+omit them entirely.
+
 ## Troubleshooting
 
 ### Conan
@@ -583,14 +381,18 @@ After any updates or changes to dependencies, you may need to do the following:
    conan remove '*'
    ```
 
-3. Re-run [conan export](#patched-recipes) if needed.
-4. [Regenerate lockfile](#conan-lockfile).
+3. Re-run [conan export](./docs/build/advanced_conan.md#patched-recipes) if needed.
+4. [Regenerate lockfile](./docs/build/advanced_conan.md#conan-lockfile).
 5. Re-run [conan install](#build-and-test).
 
+If you are using the Nix development shell, whether prebuilt Conan binaries apply
+depends on your platform — see
+[Prebuilt packages](./docs/build/nix.md#prebuilt-packages).
+
 #### ERROR: Package not resolved
 
 If you're seeing an error like `ERROR: Package 'snappy/1.1.10' not resolved: Unable to find 'snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1756234314.246' in remotes.`,
-please add `xrplf` remote or re-run `conan export` for [patched recipes](#patched-recipes).
+please [set Conan up](#set-up-conan) so the `xrplf` remote is configured, or re-run `conan export` for [patched recipes](./docs/build/advanced_conan.md#patched-recipes).
 
 ### `protobuf/port_def.inc` file not found
 
@@ -610,28 +412,8 @@ For example, if you want to build Debug:
 1. For conan install, pass `--settings build_type=Debug`
 2. For cmake, pass `-DCMAKE_BUILD_TYPE=Debug`
 
-## Add a Dependency
-
-If you want to experiment with a new package, follow these steps:
-
-1. Search for the package on [Conan Center](https://conan.io/center/).
-2. Modify [`conanfile.py`](./conanfile.py):
-   - Add a version of the package to the `requires` property.
-   - Change any default options for the package by adding them to the
-     `default_options` property (with syntax `'$package:$option': $value`).
-3. Modify [`CMakeLists.txt`](./CMakeLists.txt):
-   - Add a call to `find_package($package REQUIRED)`.
-   - Link a library from the package to the target `xrpl_libs`
-     (search for the existing call to `target_link_libraries(xrpl_libs INTERFACE ...)`).
-4. Start coding! Don't forget to include whatever headers you need from the package.
-
-[1]: https://github.com/conan-io/conan-center-index/issues/13168
-[2]: https://en.cppreference.com/w/cpp/compiler_support/20
-[3]: https://docs.conan.io/en/latest/getting_started.html
-[5]: https://en.wikipedia.org/wiki/Unity_build
-[6]: https://github.com/boostorg/beast/issues/2648
-[7]: https://github.com/boostorg/beast/issues/2661
+[conan-getting-started]: https://docs.conan.io/en/latest/getting_started.html
+[unity-build]: https://en.wikipedia.org/wiki/Unity_build
 [gcovr]: https://gcovr.com/en/stable/getting-started.html
 [python-pip]: https://packaging.python.org/en/latest/guides/installing-using-pip-and-virtual-environments/
 [build_type]: https://cmake.org/cmake/help/latest/variable/CMAKE_BUILD_TYPE.html
-[profile]: https://docs.conan.io/en/latest/reference/profiles.html

CMakeLists.txt

@@ -13,9 +13,26 @@ if(DEFINED CMAKE_MODULE_PATH)
 endif()
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
+# Must be set before project() because project() consumes it when configuring the compiler and SDK.
+# A user-provided -DCMAKE_OSX_DEPLOYMENT_TARGET still takes precedence.
+#
+# CMAKE_SYSTEM_NAME can't be used before project(), so CMAKE_HOST_SYSTEM_NAME is used instead.
+#
+# When CMAKE_OSX_DEPLOYMENT_TARGET is bumped to >=26.0, FastFloat dependency won't be needed anymore
+if(
+    CMAKE_HOST_SYSTEM_NAME STREQUAL "Darwin"
+    AND NOT DEFINED CMAKE_OSX_DEPLOYMENT_TARGET
+)
+    set(CMAKE_OSX_DEPLOYMENT_TARGET
+        "15.0"
+        CACHE STRING
+        "Minimum macOS deployment version"
+    )
+endif()
+
 project(xrpl)
 set(CMAKE_CXX_EXTENSIONS OFF)
-set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD 23)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
@@ -57,6 +74,8 @@ if(target)
     )
 endif()
 
+include(PatchNixBinary)
+
 include(XrplSanity)
 include(XrplVersion)
 include(XrplSettings)
@@ -85,9 +104,11 @@ include(deps/Boost)
 add_subdirectory(external/antithesis-sdk)
 find_package(date REQUIRED)
 find_package(ed25519 REQUIRED)
+find_package(FastFloat REQUIRED)
 find_package(gRPC REQUIRED)
 find_package(LibArchive REQUIRED)
 find_package(lz4 REQUIRED)
+find_package(mpt-crypto REQUIRED)
 find_package(nudb REQUIRED)
 find_package(OpenSSL REQUIRED)
 find_package(secp256k1 REQUIRED)
@@ -99,7 +120,9 @@ target_link_libraries(
     xrpl_libs
     INTERFACE
         ed25519::ed25519
+        FastFloat::fast_float
         lz4::lz4
+        mpt-crypto::mpt-crypto
         OpenSSL::Crypto
         OpenSSL::SSL
         secp256k1::secp256k1
@@ -127,17 +150,33 @@ else()
 endif()
 target_link_libraries(xrpl_libs INTERFACE ${nudb})
 
+if(benchmark)
+    find_package(benchmark REQUIRED)
+endif()
+
 if(coverage)
     include(XrplCov)
 endif()
 
+add_custom_target(tidy_prerequisites)
+
+if(rust)
+    add_subdirectory(crates)
+endif()
 include(XrplCore)
+
 include(XrplProtocolAutogen)
 include(XrplInstall)
-include(XrplPackaging)
 include(XrplValidatorKeys)
+# Must come after XrplValidatorKeys: the 'package' target depends on the
+# validator-keys target existing.
+include(XrplPackaging)
 
 if(tests)
     include(CTest)
     add_subdirectory(src/tests/libxrpl)
 endif()
+
+if(benchmark)
+    add_subdirectory(src/benchmarks/libxrpl)
+endif()

CODEOWNERS

@@ -0,0 +1,4 @@
+# By default, anyone can review changes.
+
+# The CI tooling team should review changes to the CI configuration.
+/.github/ @XRPLF/ci-tooling

CONTRIBUTING.md

@@ -14,9 +14,9 @@ The following branches exist in the main project repository:
 
 - `develop`: The latest set of unreleased features, and the most common
   starting point for contributions.
-- `release`: The latest beta release or release candidate.
-- `master`: The latest stable release.
-- `gh-pages`: The documentation for this project, built by Doxygen.
+- `release/*` (e.g. `release/3.2.x`): Release branches, one per release line,
+  holding the latest release candidate, or stable release for that line.
+  Stable releases are published as [tagged releases](https://github.com/XRPLF/rippled/releases).
 
 The tip of each branch must be signed. In order for GitHub to sign a
 squashed commit that it builds from your pull request, GitHub must know
@@ -83,8 +83,11 @@ If you create new source files, they must be organized as follows:
   `src/libxrpl`.
 - All other non-test files must go under `src/xrpld`.
 - All test source files must go under `src/test`.
+- All benchmark source files must go under `src/benchmarks`.
 
-The source must be formatted according to the style guide below.
+The source must be formatted according to the style guide below. The easiest
+way to satisfy this is to install the [`pre-commit`](#pre-commit-hooks) hooks,
+which format and lint your changes automatically on every commit.
 
 Header includes must be [levelized](.github/scripts/levelization).
 
@@ -130,11 +133,9 @@ tl;dr
 ## Pull requests
 
 In general, pull requests use `develop` as the base branch.
-The exceptions are
 
-- Fixes and improvements to a release candidate use `release` as the
-  base.
-- Hotfixes use `master` as the base.
+The exceptions are fixes, improvements, and hotfixes for an existing release,
+which use that release's branch (e.g. `release/3.2.x`) as the base.
 
 If your changes are not quite ready, but you want to make it easily available
 for preliminary examination or review, you can create a "Draft" pull request.
@@ -214,13 +215,63 @@ This is a non-exhaustive list of recommended style guidelines. These are
 not always strictly enforced and serve as a way to keep the codebase
 coherent rather than a set of _thou shalt not_ commandments.
 
+## Pre-commit hooks
+
+We use the [`pre-commit`](https://pre-commit.com/) framework to run the
+formatting and linting tools that keep the codebase consistent. `pre-commit`
+runs each tool configured in
+[`.pre-commit-config.yaml`](./.pre-commit-config.yaml) in its own isolated
+environment, so you don't need to install most of the individual tools
+yourself. The version of each hook sourced from an external repository
+(`clang-format`, `gersemi`, etc.) is pinned in that file, so running the hooks
+locally uses exactly the same versions as CI. A few `local` hooks — most notably
+`clang-tidy` and `cargo fmt` — run tools from your own environment; see
+[Installing clang-tidy](#installing-clang-tidy) and
+[Rust](./docs/build/environment.md#rust) for how to get those.
+
+To get started, install `pre-commit` and enable the git hook scripts:
+
+```bash
+pip install pre-commit
+pre-commit install
+```
+
+Once installed, the hooks run automatically on your staged files every time you
+`git commit`. You can also run them on demand:
+
+```bash
+# Run all hooks against only the staged files
+pre-commit run
+
+# Run all hooks against every file in the repository
+pre-commit run --all-files
+
+# Run a single hook (e.g. clang-format) against all files
+pre-commit run clang-format --all-files
+```
+
+The hooks configured in this repository include, among others:
+
+- `clang-format` — C++/proto formatting (see [Formatting](#formatting))
+- `clang-tidy` — C++ static analysis (see [Clang-tidy](#clang-tidy)); opt in with `TIDY=1`
+- `fix-include-style`, `fix-pragma-once`, `check-doxygen-style` — C++ hygiene
+- `gersemi` — CMake formatting
+- `cargo fmt` — Rust formatting for the crates in `crates/`
+- `prettier`, `black`, `shfmt` — formatting for JavaScript/JSON/Markdown, Python, and shell
+- `cspell` — spell checking
+
+The same hooks run in CI on every pull request, so running them locally before
+you push helps you avoid CI failures.
+
 ## Formatting
 
-All code must conform to `clang-format` version 21,
-according to the settings in [`.clang-format`](./.clang-format),
-unless the result would be unreasonably difficult to read or maintain.
-To demarcate lines that should be left as-is, surround them with comments like
-this:
+All code must conform to `clang-format`, according to the settings in
+[`.clang-format`](./.clang-format), unless the result would be unreasonably
+difficult to read or maintain. The `clang-format` version is pinned in
+[`.pre-commit-config.yaml`](./.pre-commit-config.yaml), so the
+[`pre-commit`](#pre-commit-hooks) hook always formats with the same version as
+CI. To demarcate lines that should be left as-is, surround them with comments
+like this:
 
 ```
 // clang-format off
@@ -228,9 +279,21 @@ this:
 // clang-format on
 ```
 
-You can format individual files in place by running `clang-format -i <file>...`
+The easiest way to format your changes is to let the `pre-commit` hook run
+automatically on commit, or to run it manually:
+
+```bash
+pre-commit run clang-format --all-files
+```
+
+You can also format individual files in place by running `clang-format -i <file>...`
 from any directory within this project.
 
+> [!NOTE]
+> This uses whatever `clang-format` version is installed locally, which may
+> differ from the pinned version used by `pre-commit` and CI, so the results
+> can vary.
+
 There is a Continuous Integration job that runs clang-format on pull requests. If the code doesn't comply, a patch file that corrects auto-fixable formatting issues is generated.
 
 To download the patch file:
@@ -241,13 +304,6 @@ To download the patch file:
 4. Download the zip file and extract it to your local git repository. Run `git apply [patch-file-name]`.
 5. Commit and push.
 
-You can install a pre-commit hook to automatically run `clang-format` before every commit:
-
-```
-pip3 install pre-commit
-pre-commit install
-```
-
 ## Clang-tidy
 
 All code must pass `clang-tidy` checks according to the settings in [`.clang-tidy`](./.clang-tidy).
@@ -261,15 +317,19 @@ This ensures that configuration changes don't introduce new warnings across the
 
 ### Installing clang-tidy
 
-See the [environment setup guide](./docs/build/environment.md#clang-tidy) for platform-specific installation instructions.
+See the [environment setup guide](./docs/build/environment.md#clang-tidy) for how to get clang-tidy.
 
 ### Running clang-tidy locally
 
-Before running clang-tidy, you must build the project to generate required files (particularly protobuf headers). Refer to [`BUILD.md`](./BUILD.md) for build instructions.
+Before running clang-tidy, you must generate the files it depends on (protobuf headers, and, when the project is configured with `-Drust=ON`, the cxxbridge headers from the Rust crates). Configure the project as described in [`BUILD.md`](./BUILD.md), then build the `tidy_prerequisites` target, which generates all of them:
+
+```bash
+cmake --build build --target tidy_prerequisites
+```
 
 #### Via pre-commit (recommended)
 
-If you have already installed the pre-commit hooks (see above), you can run clang-tidy on your staged files using:
+If you have already installed the [`pre-commit`](#pre-commit-hooks) hooks, you can run clang-tidy on your staged files using:
 
 ```
 TIDY=1 pre-commit run clang-tidy
@@ -294,12 +354,54 @@ run-clang-tidy -p build -allow-no-checks src tests
 ```
 
 This will check all source files in the `src`, `include` and `tests` directories using the compile commands from your `build` directory.
-If you wish to automatically fix whatever clang-tidy finds _and_ is capable of fixing, add `-fix` to the above command:
+If you wish to automatically fix whatever clang-tidy finds _and_ is capable of fixing, add `-fix -format` to the above command:
 
 ```
-run-clang-tidy -p build -quiet -fix -allow-no-checks src tests
+run-clang-tidy -p build -quiet -fix -format -allow-no-checks src tests
 ```
 
+`-format` reformats the fixed code with [`.clang-format`](./.clang-format); without it the fixes are inserted in LLVM style and the `clang-format` hook rewrites them afterwards.
+
+## Telemetry span attribute naming
+
+OpenTelemetry span attribute keys follow these rules so they stay consistent
+across the code, the OTel collector, Tempo, Grafana dashboards, and docs. The
+constants in the `*SpanNames.h` headers are the single source of truth; every
+other layer must match them. A CI check enforces this end to end.
+
+1. Per-span unique attribute: bare field name — allowed when the field is
+   recorded by a single span/workflow, so the span name already supplies the
+   domain (e.g. `command`, `local`, `version` on `rpc.command` / `tx.process`).
+2. Shared attribute (same concept on more than one span): ONE key, reused
+   verbatim on every span that records it — the span name tells the occurrences
+   apart, so no per-emitter prefix is added. Pick the name by the field's
+   meaning: a property of a domain object keeps that object's bare field name
+   (`ledger_hash`, `ledger_seq`, `tx_hash`, `peer_id`, `full_validation`); a
+   field already qualified by a sub-kind keeps that qualifier on every emitter
+   (`proposal_trusted` on both `consensus.proposal.receive` and
+   `peer.proposal.receive`; `validation_trusted` likewise). Define it once in
+   the base `SpanNames.h` `namespace attr` block and re-export (`using`) it from
+   each domain header, so all emitters share the exact string.
+3. Collision qualifier: `<domain>_<field>` — only when a bare name would collide
+   with a DIFFERENT concept in the shared spanmetrics label space, or with the
+   OTel-reserved `status` key (e.g. `rpc_status`, `grpc_status`,
+   `consensus_phase`, `consensus_round`). This disambiguates distinct concepts
+   that share a word; it is NOT used to tag the same concept with the workflow
+   that emitted it — that is rule 2 (one shared name).
+4. Resource attribute: dotted `xrpl.<subsystem>.<field>` — reserved ONLY for
+   process/network identity set once at startup (`xrpl.network.id`,
+   `xrpl.network.type`). Never use the dotted `xrpl.` form for span attributes.
+5. Span names use `<subsystem>[.<component>]` (dotted). Only attribute _keys_
+   follow rules 1–4.
+
+Standard OpenTelemetry semantic-convention keys keep their canonical dotted
+form (e.g. `service.*` resource attributes, `http.*` span attributes); the
+"no dotted form" rule above applies to xrpl-custom keys, not to OTel-standard
+conventions.
+
+Always reference the `*SpanNames.h` constants — never pass string literals as
+attribute keys or values to `setAttribute`/`addEvent`.
+
 ## Contracts and instrumentation
 
 We are using [Antithesis](https://antithesis.com/) for continuous fuzzing,

OpenTelemetryPlan/00-tracing-fundamentals.md

@@ -0,0 +1,565 @@
+# Distributed Tracing Fundamentals
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Next**: [Architecture Analysis](./01-architecture-analysis.md)
+
+---
+
+## What is Distributed Tracing?
+
+Distributed tracing is a method for tracking data objects as they flow through distributed systems. In a network like XRP Ledger, a single transaction touches multiple independent nodes—each with no shared memory or logging. Distributed tracing connects these dots.
+
+**Without tracing:** You see isolated logs on each node with no way to correlate them.
+
+**With tracing:** You see the complete journey of a transaction or an event across all nodes it touched.
+
+---
+
+## Actors and Actions at a Glance
+
+### Actors
+
+| Who (Plain English)                            | Technical Term  |
+| ---------------------------------------------- | --------------- |
+| A single unit of work being tracked            | Span            |
+| The complete journey of a request              | Trace           |
+| Data that links spans across services          | Trace Context   |
+| Code that creates spans and propagates context | Instrumentation |
+| Service that receives and processes traces     | Collector       |
+| Storage and visualization system               | Backend (Tempo) |
+| Decision logic for which traces to keep        | Sampler         |
+
+### Actions
+
+| What Happens (Plain English)            | Technical Term          |
+| --------------------------------------- | ----------------------- |
+| Start tracking a new operation          | Create a Span           |
+| Connect a child operation to its parent | Set `parent_span_id`    |
+| Group all related operations together   | Share a `trace_id`      |
+| Pass tracking data between services     | Context Propagation     |
+| Decide whether to record a trace        | Sampling (Head or Tail) |
+| Send completed traces to storage        | Export (OTLP)           |
+
+---
+
+## Core Concepts
+
+### 1. Trace
+
+A **trace** represents the entire journey of a request through the system. It has a unique `trace_id` that stays constant across all nodes.
+
+```
+Trace ID: abc123
+├── Node A: received transaction
+├── Node B: relayed transaction
+├── Node C: included in consensus
+└── Node D: applied to ledger
+```
+
+### 2. Span
+
+A **span** represents a single unit of work within a trace. Each span has:
+
+| Attribute        | Description                      | Example                    |
+| ---------------- | -------------------------------- | -------------------------- |
+| `trace_id`       | Identifies the trace             | `event123`                 |
+| `span_id`        | Unique identifier                | `span456`                  |
+| `parent_span_id` | Parent span (if any)             | `p_span123`                |
+| `name`           | Operation name                   | `rpc.submit`               |
+| `start_time`     | When work began (local time)     | `2024-01-15T10:30:00Z`     |
+| `end_time`       | When work completed (local time) | `2024-01-15T10:30:00.050Z` |
+| `attributes`     | Key-value metadata               | `tx_hash=ABC...`           |
+| `status`         | OK, ERROR MSG                    | `OK`                       |
+
+### 3. Trace Context
+
+**Trace context** is the data that propagates between services to link spans together. It contains:
+
+- `trace_id` - The trace this span belongs to
+- `span_id` - The current span (becomes parent for child spans)
+- `trace_flags` - Sampling decisions
+
+---
+
+## How Spans Form a Trace
+
+Spans have parent-child relationships forming a tree structure:
+
+```mermaid
+flowchart TB
+    subgraph trace["Trace: abc123"]
+        A["tx.submit<br/>span_id: 001<br/>50ms"] --> B["tx.validate<br/>span_id: 002<br/>5ms"]
+        A --> C["tx.relay<br/>span_id: 003<br/>10ms"]
+        A --> D["tx.apply<br/>span_id: 004<br/>30ms"]
+        D --> E["ledger.update<br/>span_id: 005<br/>20ms"]
+    end
+
+    style A fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style B fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style C fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style D fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style E fill:#bf360c,stroke:#8c2809,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **tx.submit (blue, root)**: The top-level span representing the entire transaction submission; all other spans are its descendants.
+- **tx.validate, tx.relay, tx.apply (green)**: Direct children of tx.submit, representing the three main stages -- validation, relay to peers, and application to the ledger.
+- **ledger.update (red)**: A grandchild span nested under tx.apply, representing the actual ledger state mutation triggered by applying the transaction.
+- **Arrows (parent to child)**: Each arrow indicates a parent-child span relationship where the parent's completion depends on the child finishing.
+
+The same trace visualized as a **timeline (Gantt chart)**:
+
+```
+Time →   0ms    10ms    20ms    30ms    40ms    50ms
+         ├───────────────────────────────────────────┤
+tx.submit│▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓│
+         ├─────┤
+tx.valid │▓▓▓▓▓│
+         │     ├──────────┤
+tx.relay │     │▓▓▓▓▓▓▓▓▓▓│
+         │               ├────────────────────────────┤
+tx.apply │               │▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓│
+         │                         ├──────────────────┤
+ledger   │                         │▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓│
+```
+
+---
+
+## Span Relationships
+
+Spans don't always form simple parent-child trees. Distributed tracing defines several relationship types to capture different causal patterns:
+
+### 1. Parent-Child (ChildOf)
+
+The default relationship. The parent span **depends on** or **contains** the child span. The child runs within the scope of the parent.
+
+```
+tx.submit (parent)
+├── tx.validate (child)     ← parent waits for this
+├── tx.relay (child)        ← parent waits for this
+└── tx.apply (child)        ← parent waits for this
+```
+
+**When to use:** Synchronous calls, nested operations, any case where the parent's completion depends on the child.
+
+### 2. Follows-From
+
+A causal relationship where the first span **triggers** the second, but does **not wait** for it. The originator fires and moves on.
+
+```
+Time →
+
+tx.receive [=======]
+                     ↓ triggers (follows-from)
+              tx.relay   [===========]   ← runs independently
+```
+
+**When to use:** Asynchronous jobs, queued work, fire-and-forget patterns. For example, a node receives a transaction and queues it for relay — the relay span _follows from_ the receive span but the receiver doesn't wait for relaying to complete.
+
+> **OpenTracing** defined `FollowsFrom` as a first-class reference type alongside `ChildOf`.
+> **OpenTelemetry** represents this using **Span Links** with descriptive attributes instead (see below).
+
+### 3. Span Links (Cross-Trace and Non-Hierarchical)
+
+Links connect spans that are **causally related but not in a parent-child hierarchy**. Unlike parent-child, links can cross trace boundaries.
+
+```
+Trace A                          Trace B
+──────                           ──────
+batch.schedule                   batch.execute
+├─ item.enqueue (span X)    ┌──► process.item
+├─ item.enqueue (span Y) ───┤    (links to X, Y, Z)
+├─ item.enqueue (span Z)    └──►
+```
+
+**Use cases:**
+
+| Pattern              | Description                                                                 |
+| -------------------- | --------------------------------------------------------------------------- |
+| **Batch processing** | A batch span links back to all individual spans that contributed to it      |
+| **Fan-in**           | An aggregation span links to the multiple producer spans it merges          |
+| **Fan-out**          | Multiple downstream spans link back to the single span that triggered them  |
+| **Async handoff**    | A deferred job links back to the request that queued it (follows-from)      |
+| **Cross-trace**      | Correlating spans across independent traces (e.g., retries, related events) |
+
+**Link structure:** Each link carries the target span's context plus optional attributes:
+
+```
+Link {
+    trace_id:   <target trace>
+    span_id:    <target span>
+    attributes: { "link.description": "triggered by batch scheduler" }
+}
+```
+
+### Relationship Summary
+
+```mermaid
+flowchart LR
+    subgraph parent_child["Parent-Child"]
+        direction TB
+        P["Parent"] --> C["Child"]
+    end
+
+    subgraph follows_from["Follows-From"]
+        direction TB
+        A["Span A"] -.->|triggers| B["Span B"]
+    end
+
+    subgraph links["Span Links"]
+        direction TB
+        X["Span X\n(Trace 1)"] -.-|link| Y["Span Y\n(Trace 2)"]
+    end
+
+    parent_child ~~~ follows_from ~~~ links
+
+    style P fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style C fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style A fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style B fill:#bf360c,stroke:#8c2809,color:#ffffff
+    style X fill:#4a148c,stroke:#38006b,color:#ffffff
+    style Y fill:#4a148c,stroke:#38006b,color:#ffffff
+```
+
+| Relationship     | Same Trace? | Dependency?                | OTel Mechanism    |
+| ---------------- | ----------- | -------------------------- | ----------------- |
+| **Parent-Child** | Yes         | Parent depends on child    | `parent_span_id`  |
+| **Follows-From** | Usually     | Causal but no dependency   | Link + attributes |
+| **Span Link**    | Either      | Correlation, no dependency | Link + attributes |
+
+---
+
+## Trace ID Generation
+
+A `trace_id` is a 128-bit (16-byte) identifier that groups all spans belonging to one logical operation. How it's generated determines how easily you can find and correlate traces later.
+
+### General Approaches
+
+#### 1. Random (W3C Default)
+
+Generate a random 128-bit ID when a trace starts. Standard approach for most services.
+
+```
+trace_id = random_128_bits()
+```
+
+| Pros                        | Cons                                          |
+| --------------------------- | --------------------------------------------- |
+| Simple, standard            | No natural correlation to domain events       |
+| Guaranteed unique per trace | If propagation is lost, trace is broken       |
+| Works with all OTel tooling | "Find trace for TX abc" requires index lookup |
+
+#### 2. Deterministic (Derived from Domain Data)
+
+Compute the trace_id from a hash of a natural identifier. Every node independently derives the **same** trace_id for the same event.
+
+```
+trace_id = SHA-256(domain_identifier)[0:16]   // truncate to 128 bits
+```
+
+| Pros                                                | Cons                                                       |
+| --------------------------------------------------- | ---------------------------------------------------------- |
+| Propagation-resilient — same ID computed everywhere | Same event processed twice (retry) shares trace_id         |
+| Natural search — domain ID maps directly to trace   | Non-standard (tooling assumes random)                      |
+| No coordination needed between nodes                | 256→128 bit truncation (collision risk negligible at ~2⁶⁴) |
+
+#### 3. Hybrid (Deterministic Prefix + Random Suffix)
+
+First 8 bytes derived from domain data, last 8 bytes random.
+
+```
+trace_id = SHA-256(domain_identifier)[0:8] || random_64_bits()
+```
+
+| Pros                                        | Cons                                     |
+| ------------------------------------------- | ---------------------------------------- |
+| Prefix search: "find all traces for TX abc" | Must propagate to maintain full trace_id |
+| Unique per processing instance              | More complex generation logic            |
+| Retries get distinct trace_ids              | Partial correlation only (prefix match)  |
+
+### XRPL Workflow Analysis
+
+XRPL has a unique advantage: its core workflows produce **globally unique 256-bit hashes** that are known on every node. This makes deterministic trace_id generation practical in ways most systems can't achieve.
+
+#### Natural Identifiers by Workflow
+
+| Workflow            | Natural Identifier                | Size       | Known at Start?               | Same on All Nodes?               |
+| ------------------- | --------------------------------- | ---------- | ----------------------------- | -------------------------------- |
+| **Transaction**     | Transaction hash (`tid_`)         | 256-bit    | Yes — computed before signing | Yes — hash of canonical tx data  |
+| **Consensus round** | Previous ledger hash + ledger seq | 256+32 bit | Yes — known when round opens  | Yes — all validators agree       |
+| **Validation**      | Ledger hash being validated       | 256-bit    | Yes — from consensus result   | Yes — same closed ledger         |
+| **Ledger catch-up** | Target ledger hash                | 256-bit    | Yes — we know what to fetch   | Yes — identifies ledger globally |
+
+#### Where These Identifiers Live in Code
+
+```
+Transaction:     STTx::getTransactionID()     → uint256 tid_
+                 TMTransaction::rawTransaction → recompute hash from bytes
+
+Consensus:       ConsensusProposal::prevLedger_ → uint256 (previous ledger hash)
+                 ConsensusProposal::position_   → uint256 (TxSet hash)
+                 LedgerHeader::seq              → uint32_t (ledger sequence)
+
+Validation:      STValidation::getLedgerHash()  → uint256
+                 STValidation::getNodeID()      → NodeID (160-bit)
+
+Ledger fetch:    InboundLedger constructor      → uint256 hash, uint32_t seq
+                 TMGetLedger::ledgerHash        → bytes (uint256)
+```
+
+### Recommended Strategy: Workflow-Scoped Deterministic
+
+Each workflow type derives its trace_id from its natural domain identifier:
+
+```
+Transaction trace:   trace_id = SHA-256("tx"    || tx_hash)[0:16]
+Consensus trace:     trace_id = SHA-256("cons"  || prev_ledger_hash || ledger_seq)[0:16]
+Ledger catch-up:     trace_id = SHA-256("fetch" || target_ledger_hash)[0:16]
+```
+
+The string prefix (`"tx"`, `"cons"`, `"fetch"`) prevents collisions between workflows that might share underlying hashes.
+
+**Why this works for XRPL:**
+
+1. **Propagation-resilient** — Even if a P2P message drops trace context, every node independently computes the same trace_id from the same tx_hash or ledger_hash. Spans still correlate.
+
+2. **Zero-cost search** — "Show me the trace for transaction ABC" becomes a direct lookup: compute `SHA-256("tx" || ABC)[0:16]` and query. No secondary index needed.
+
+3. **Cross-workflow linking via Span Links** — A consensus trace links to individual transaction traces. A validation span links to the consensus trace. This connects the full picture without forcing everything into one giant trace.
+
+### Cross-Workflow Correlation
+
+Each workflow gets its own trace. Span Links tie them together:
+
+```mermaid
+flowchart TB
+    subgraph tx_trace["Transaction Trace"]
+        direction LR
+        Tn["trace_id = f(tx_hash)"]:::note --> T1["tx.receive"] --> T2["tx.validate"] --> T3["tx.relay"]
+    end
+
+    subgraph cons_trace["Consensus Trace"]
+        direction LR
+        Cn["trace_id = f(prev_ledger, seq)"]:::note --> C1["cons.open"] --> C2["cons.propose"] --> C3["cons.accept"]
+    end
+
+    subgraph val_trace["Validation"]
+        direction LR
+        Vn["spans within consensus trace"]:::note --> V1["val.create"] --> V2["val.broadcast"]
+    end
+
+    subgraph fetch_trace["Catch-Up Trace"]
+        direction LR
+        Fn["trace_id = f(ledger_hash)"]:::note --> F1["fetch.request"] --> F2["fetch.receive"] --> F3["fetch.apply"]
+    end
+
+    C1 -.-|"span link\n(tx traces)"| T3
+    C3 --> V1
+    F1 -.-|"span link\n(target ledger)"| C3
+
+    classDef note fill:none,stroke:#888,stroke-dasharray:5 5,color:#333,font-style:italic
+    style T1 fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style T2 fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style T3 fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style C1 fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style C2 fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style C3 fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style V1 fill:#bf360c,stroke:#8c2809,color:#ffffff
+    style V2 fill:#bf360c,stroke:#8c2809,color:#ffffff
+    style F1 fill:#4a148c,stroke:#38006b,color:#ffffff
+    style F2 fill:#4a148c,stroke:#38006b,color:#ffffff
+    style F3 fill:#4a148c,stroke:#38006b,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **Transaction Trace (blue)**: An independent trace whose `trace_id` is deterministically derived from the transaction hash. Contains receive, validate, and relay spans.
+- **Consensus Trace (green)**: An independent trace whose `trace_id` is derived from the previous ledger hash and sequence number. Covers the open, propose, and accept phases.
+- **Validation (red)**: Validation spans live within the consensus trace (not a separate trace). They are created after the accept phase completes.
+- **Catch-Up Trace (purple)**: An independent trace for ledger acquisition, derived from the target ledger hash. Used when a node is behind and fetching missing ledgers.
+- **Dotted arrows (span links)**: Cross-trace correlations. Consensus links to transaction traces it included; catch-up links to the consensus trace that produced the target ledger.
+- **Solid arrow (C3 to V1)**: A parent-child relationship -- validation spans are direct children of the consensus accept span within the same trace.
+
+**How a query flows:**
+
+```
+"Why was TX abc slow?"
+  1. Compute trace_id = SHA-256("tx" || abc)[0:16]
+  2. Find transaction trace → see it was included in consensus round N
+  3. Follow span link → consensus trace for round N
+  4. See which phase was slow (propose? accept?)
+  5. If a node was catching up, follow link → catch-up trace
+```
+
+### Trade-offs to Consider
+
+| Concern                       | Mitigation                                                                                                                    |
+| ----------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
+| **Retries get same trace_id** | Add `attempt` attribute to root span; spans have unique span_ids and timestamps                                               |
+| **256→128 bit truncation**    | Birthday-bound collision at ~2⁶⁴ operations — negligible for XRPL's throughput                                                |
+| **Non-standard generation**   | OTel spec allows any 16-byte non-zero value; tooling works on the hex string                                                  |
+| **Hash computation cost**     | SHA-256 is ~0.3μs per call; XRPL already computes these hashes for other purposes                                             |
+| **Late-binding identifiers**  | Ledger hash isn't known until after consensus — validation spans use ledger_seq as fallback, then link to the consensus trace |
+
+---
+
+## Distributed Traces Across Nodes
+
+In distributed systems like xrpld, traces span **multiple independent nodes**. The trace context must be propagated in network messages:
+
+```mermaid
+sequenceDiagram
+    participant Client
+    participant NodeA as Node A
+    participant NodeB as Node B
+    participant NodeC as Node C
+
+    Client->>NodeA: Submit TX<br/>(no trace context)
+
+    Note over NodeA: Creates new trace<br/>trace_id: abc123<br/>span: tx.receive
+
+    NodeA->>NodeB: Relay TX<br/>(trace_id: abc123, parent: 001)
+
+    Note over NodeB: Creates child span<br/>span: tx.relay<br/>parent_span_id: 001
+
+    NodeA->>NodeC: Relay TX<br/>(trace_id: abc123, parent: 001)
+
+    Note over NodeC: Creates child span<br/>span: tx.relay<br/>parent_span_id: 001
+
+    Note over NodeA,NodeC: All spans share trace_id: abc123<br/>enabling correlation across nodes
+```
+
+**Reading the diagram:**
+
+- **Client**: The external entity that submits a transaction. It does not carry trace context -- the trace originates at the first node.
+- **Node A**: The entry point that creates a new trace (trace_id: abc123) and the root span `tx.receive`. It relays the transaction to peers with trace context attached.
+- **Node B and Node C**: Peer nodes that receive the relayed transaction along with the propagated trace context. Each creates a child span under Node A's span, preserving the same `trace_id`.
+- **Arrows with trace context**: The relay messages carry `trace_id` and `parent_span_id`, allowing each downstream node to link its spans back to the originating span on Node A.
+
+---
+
+## Context Propagation
+
+For traces to work across nodes, **trace context must be propagated** in messages.
+
+### What's in the Context (~26 bytes)
+
+| Field         | Size     | Description                                             |
+| ------------- | -------- | ------------------------------------------------------- |
+| `trace_id`    | 16 bytes | Identifies the entire trace (constant across all nodes) |
+| `span_id`     | 8 bytes  | The sender's current span (becomes parent on receiver)  |
+| `trace_flags` | 1 byte   | Sampling decision (bit 0 = sampled; bits 1-7 reserved)  |
+| `trace_state` | variable | Optional vendor-specific data (typically omitted)       |
+
+### How span_id Changes at Each Hop
+
+Only **one** `span_id` travels in the context - the sender's current span. Each node:
+
+1. Extracts the received `span_id` and uses it as the `parent_span_id`
+2. Creates a **new** `span_id` for its own span
+3. Sends its own `span_id` as the parent when forwarding
+
+```
+Node A                      Node B                      Node C
+──────                      ──────                      ──────
+
+Span AAA                    Span BBB                    Span CCC
+   │                           │                           │
+   ▼                           ▼                           ▼
+Context out:                Context out:                Context out:
+├─ trace_id: abc123         ├─ trace_id: abc123         ├─ trace_id: abc123
+├─ span_id: AAA ──────────► ├─ span_id: BBB ──────────► ├─ span_id: CCC ──────►
+└─ flags: 01                └─ flags: 01                └─ flags: 01
+                               │                           │
+                          parent = AAA               parent = BBB
+```
+
+The `trace_id` stays constant, but `span_id` **changes at every hop** to maintain the parent-child chain.
+
+### Propagation Formats
+
+There are two patterns:
+
+### HTTP/RPC Headers (W3C Trace Context)
+
+```
+traceparent: 00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01
+             │  │                                │                │
+             │  │                                │                └── Flags (sampled)
+             │  │                                └── Parent span ID (16 hex)
+             │  └── Trace ID (32 hex)
+             └── Version
+```
+
+### Protocol Buffers (xrpld P2P messages)
+
+xrpld P2P messages such as `TMTransaction` carry the trace context in two added byte fields alongside the existing payload: `trace_parent` holds the W3C traceparent (`trace_id`, `span_id`, and `trace_flags`), and `trace_state` holds the optional W3C tracestate. Together they propagate the trace across the P2P boundary so a receiving node can attach its spans to the sender's span.
+
+---
+
+## Sampling
+
+Not every trace needs to be recorded. **Sampling** reduces overhead:
+
+### Head Sampling (at trace start)
+
+```
+Request arrives → Random N% chance → Record or skip entire trace
+```
+
+- ✅ Low overhead
+- ❌ May miss interesting traces
+
+> **xrpld note**: xrpld intentionally fixes head sampling at 100% (sample
+> everything) and does not expose a configurable ratio. A per-node ratio
+> would let different nodes make divergent keep/drop decisions for the same
+> distributed trace, producing broken/partial traces. xrpld uses a
+> `ParentBased` sampler so spans with a remote parent honor the upstream
+> decision. Volume reduction is delegated to collector-side tail sampling.
+
+### Tail Sampling (after trace completes)
+
+```
+Trace completes → Collector evaluates:
+                  - Error? → KEEP
+                  - Slow? → KEEP
+                  - Normal? → Sample 10%
+```
+
+- ✅ Never loses important traces
+- ❌ Higher memory usage at collector
+
+---
+
+## Key Benefits for xrpld
+
+| Challenge                          | How Tracing Helps                        |
+| ---------------------------------- | ---------------------------------------- |
+| "Where is my transaction?"         | Follow trace across all nodes it touched |
+| "Why was consensus slow?"          | See timing breakdown of each phase       |
+| "Which node is the bottleneck?"    | Compare span durations across nodes      |
+| "What happened during the outage?" | Correlate errors across the network      |
+
+---
+
+## Glossary
+
+| Term                 | Definition                                                          |
+| -------------------- | ------------------------------------------------------------------- |
+| **Trace**            | Complete journey of a request, identified by `trace_id`             |
+| **Span**             | Single operation within a trace                                     |
+| **Parent-Child**     | Span relationship where the parent depends on the child             |
+| **Follows-From**     | Causal relationship where originator doesn't wait for the result    |
+| **Span Link**        | Non-hierarchical connection between spans, possibly across traces   |
+| **Deterministic ID** | Trace ID derived from domain data (e.g., tx_hash) instead of random |
+| **Context**          | Data propagated between services (`trace_id`, `span_id`, flags)     |
+| **Instrumentation**  | Code that creates spans and propagates context                      |
+| **Collector**        | Service that receives, processes, and exports traces                |
+| **Backend**          | Storage/visualization system (Tempo)                                |
+| **Head Sampling**    | Sampling decision at trace start                                    |
+| **Tail Sampling**    | Sampling decision after trace completes                             |
+
+---
+
+_Next: [Architecture Analysis](./01-architecture-analysis.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/01-architecture-analysis.md

@@ -0,0 +1,467 @@
+# Architecture Analysis
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Design Decisions](./02-design-decisions.md) | [Implementation Strategy](./03-implementation-strategy.md)
+
+---
+
+## 1.1 Current xrpld Architecture Overview
+
+> **WS** = WebSocket | **UNL** = Unique Node List | **TxQ** = Transaction Queue | **StatsD** = Statistics Daemon
+
+The xrpld node software consists of several interconnected components that need instrumentation for distributed tracing:
+
+```mermaid
+flowchart TB
+    subgraph xrpld["xrpld Node"]
+        subgraph services["Core Services"]
+            RPC["RPC Server<br/>(HTTP/WS/gRPC)"]
+            Overlay["Overlay<br/>(P2P Network)"]
+            Consensus["Consensus<br/>(RCLConsensus)"]
+            ValidatorList["ValidatorList<br/>(UNL Mgmt)"]
+        end
+
+        JobQueue["JobQueue<br/>(Thread Pool)"]
+
+        subgraph processing["Processing Layer"]
+            NetworkOPs["NetworkOPs<br/>(Tx Processing)"]
+            LedgerMaster["LedgerMaster<br/>(Ledger Mgmt)"]
+            NodeStore["NodeStore<br/>(Database)"]
+            InboundLedgers["InboundLedgers<br/>(Ledger Sync)"]
+        end
+
+        subgraph appservices["Application Services"]
+            PathFind["PathFinding<br/>(Payment Paths)"]
+            TxQ["TxQ<br/>(Fee Escalation)"]
+            LoadMgr["LoadManager<br/>(Fee/Load)"]
+        end
+
+        subgraph observability["Existing Observability"]
+            PerfLog["PerfLog<br/>(JSON)"]
+            Insight["Insight<br/>(StatsD)"]
+            Logging["Logging<br/>(Journal)"]
+        end
+
+        services --> JobQueue
+        JobQueue --> processing
+        JobQueue --> appservices
+    end
+
+    style xrpld fill:#424242,stroke:#212121,color:#ffffff
+    style services fill:#1565c0,stroke:#0d47a1,color:#ffffff
+    style processing fill:#2e7d32,stroke:#1b5e20,color:#ffffff
+    style appservices fill:#6a1b9a,stroke:#4a148c,color:#ffffff
+    style observability fill:#e65100,stroke:#bf360c,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **Core Services (blue)**: The entry points into xrpld -- RPC Server handles client requests, Overlay manages peer-to-peer networking, Consensus drives agreement, and ValidatorList manages trusted validators.
+- **JobQueue (center)**: The asynchronous thread pool that decouples Core Services from the Processing and Application layers. All work flows through it.
+- **Processing Layer (green)**: Core business logic -- NetworkOPs processes transactions, LedgerMaster manages ledger state, NodeStore handles persistence, and InboundLedgers synchronizes missing data.
+- **Application Services (purple)**: Higher-level features -- PathFinding computes payment routes, TxQ manages fee-based queuing, and LoadManager tracks server load.
+- **Existing Observability (orange)**: The current monitoring stack (PerfLog, Insight, Journal logging) that OpenTelemetry will complement, not replace.
+- **Arrows (Services to JobQueue to layers)**: Work originates at Core Services, is enqueued onto the JobQueue, and dispatched to Processing or Application layers for execution.
+
+---
+
+## 1.1.1 Actors and Actions
+
+### Actors
+
+| Who (Plain English)                       | Technical Term             |
+| ----------------------------------------- | -------------------------- |
+| Network node running XRPL software        | xrpld node                 |
+| External client submitting requests       | RPC Client                 |
+| Network neighbor sharing data             | Peer (PeerImp)             |
+| Request handler for client queries        | RPC Server (ServerHandler) |
+| Command executor for specific RPC methods | RPCHandler                 |
+| Agreement process between nodes           | Consensus (RCLConsensus)   |
+| Transaction processing coordinator        | NetworkOPs                 |
+| Background task scheduler                 | JobQueue                   |
+| Ledger state manager                      | LedgerMaster               |
+| Payment route calculator                  | PathFinding (Pathfinder)   |
+| Transaction waiting room                  | TxQ (Transaction Queue)    |
+| Fee adjustment system                     | LoadManager                |
+| Trusted validator list manager            | ValidatorList              |
+| Protocol upgrade tracker                  | AmendmentTable             |
+| Ledger state hash tree                    | SHAMap                     |
+| Persistent key-value storage              | NodeStore                  |
+
+### Actions
+
+| What Happens (Plain English)                   | Technical Term         |
+| ---------------------------------------------- | ---------------------- |
+| Client sends a request to a node               | `rpc.request`          |
+| Node executes a specific RPC command           | `rpc.command.*`        |
+| Node receives a transaction from a peer        | `tx.receive`           |
+| Node checks if a transaction is valid          | `tx.validate`          |
+| Node forwards a transaction to neighbors       | `tx.relay`             |
+| Nodes agree on which transactions to include   | `consensus.round`      |
+| Consensus progresses through phases            | `consensus.phase.*`    |
+| Node builds a new confirmed ledger             | `ledger.build`         |
+| Node fetches missing ledger data from peers    | `ledger.acquire`       |
+| Node computes payment routes                   | `pathfind.compute`     |
+| Node queues a transaction for later processing | `txq.enqueue`          |
+| Node increases fees due to high load           | `fee.escalate`         |
+| Node fetches the latest trusted validator list | `validator.list.fetch` |
+| Node votes on a protocol amendment             | `amendment.vote`       |
+| Node synchronizes state tree data              | `shamap.sync`          |
+
+---
+
+## 1.2 Key Components for Instrumentation
+
+> **TxQ** = Transaction Queue | **UNL** = Unique Node List
+
+| Component          | Location                                   | Purpose                  | Trace Value                      |
+| ------------------ | ------------------------------------------ | ------------------------ | -------------------------------- |
+| **Overlay**        | `src/xrpld/overlay/`                       | P2P communication        | Message propagation timing       |
+| **PeerImp**        | `src/xrpld/overlay/detail/PeerImp.cpp`     | Individual peer handling | Per-peer latency                 |
+| **RCLConsensus**   | `src/xrpld/app/consensus/RCLConsensus.cpp` | Consensus algorithm      | Round timing, phase analysis     |
+| **NetworkOPs**     | `src/xrpld/app/misc/NetworkOPs.cpp`        | Transaction processing   | Tx lifecycle tracking            |
+| **ServerHandler**  | `src/xrpld/rpc/detail/ServerHandler.cpp`   | RPC entry point          | Request latency                  |
+| **RPCHandler**     | `src/xrpld/rpc/detail/RPCHandler.cpp`      | Command execution        | Per-command timing               |
+| **JobQueue**       | `src/xrpl/core/JobQueue.h`                 | Async task execution     | Queue wait times                 |
+| **PathFinding**    | `src/xrpld/app/paths/`                     | Payment path computation | Path latency, cache hits         |
+| **TxQ**            | `src/xrpld/app/misc/TxQ.cpp`               | Transaction queue/fees   | Queue depth, eviction rates      |
+| **LoadManager**    | `src/xrpld/app/main/LoadManager.cpp`       | Fee escalation/load      | Fee levels, load factors         |
+| **InboundLedgers** | `src/xrpld/app/ledger/InboundLedgers.cpp`  | Ledger acquisition       | Sync time, peer reliability      |
+| **ValidatorList**  | `src/xrpld/app/misc/ValidatorList.cpp`     | UNL management           | List freshness, fetch failures   |
+| **AmendmentTable** | `src/xrpld/app/misc/AmendmentTable.cpp`    | Protocol amendments      | Voting status, activation events |
+| **SHAMap**         | `src/xrpld/shamap/`                        | State hash tree          | Sync speed, missing nodes        |
+
+---
+
+## 1.3 Transaction Flow Diagram
+
+Transaction flow spans multiple nodes in the network. Each node creates linked spans to form a distributed trace:
+
+```mermaid
+sequenceDiagram
+    participant Client
+    participant PeerA as Peer A (Receive)
+    participant PeerB as Peer B (Relay)
+    participant PeerC as Peer C (Validate)
+
+    Client->>PeerA: 1. Submit TX
+
+    rect rgb(230, 245, 255)
+        Note over PeerA: tx.receive SPAN START
+        PeerA->>PeerA: HashRouter Deduplication
+        PeerA->>PeerA: tx.validate (child span)
+    end
+
+    PeerA->>PeerB: 2. Relay TX (with trace ctx)
+
+    rect rgb(230, 245, 255)
+        Note over PeerB: tx.receive (linked span)
+    end
+
+    PeerB->>PeerC: 3. Relay TX
+
+    rect rgb(230, 245, 255)
+        Note over PeerC: tx.receive (linked span)
+        PeerC->>PeerC: tx.process
+    end
+
+    Note over Client,PeerC: DISTRIBUTED TRACE (same trace_id: abc123)
+```
+
+**Reading the diagram:**
+
+- **Client**: The external entity that submits a transaction to Peer A. It has no trace context -- the trace starts at the first node.
+- **Peer A (Receive)**: The entry node that creates the root span `tx.receive`, runs HashRouter deduplication to avoid processing duplicates, and creates a child `tx.validate` span.
+- **Peer A to Peer B arrow**: The relay message carries trace context (trace_id + parent span_id), enabling Peer B to create a linked span under the same trace.
+- **Peer B (Relay)**: Receives the transaction and trace context, creates a `tx.receive` span linked to Peer A's trace, then relays onward.
+- **Peer C (Validate)**: Final hop in this example. Creates a linked `tx.receive` span and runs `tx.process` to fully process the transaction.
+- **Blue rectangles**: Highlight the span boundaries on each node, showing where instrumentation creates and closes spans.
+
+### Trace Structure
+
+```
+trace_id: abc123
+├── span: tx.receive (Peer A)
+│   ├── span: tx.validate
+│   └── span: tx.relay
+├── span: tx.receive (Peer B) [parent: Peer A]
+│   └── span: tx.relay
+└── span: tx.receive (Peer C) [parent: Peer B]
+    └── span: tx.process
+```
+
+---
+
+## 1.4 Consensus Round Flow
+
+Consensus rounds are multi-phase operations that benefit significantly from tracing:
+
+```mermaid
+flowchart TB
+    subgraph round["consensus.round (root span)"]
+        attrs["Attributes:<br/>ledger_seq = 12345678<br/>consensus_mode = proposing<br/>proposers = 35"]
+
+        subgraph open["consensus.phase.open"]
+            open_desc["Duration: ~3s<br/>Waiting for transactions"]
+        end
+
+        subgraph establish["consensus.phase.establish"]
+            est_attrs["proposals_received = 28<br/>disputes_resolved = 3"]
+            est_children["├── consensus.proposal.receive (×28)<br/>├── consensus.proposal.send (×1)<br/>└── consensus.dispute.resolve (×3)"]
+        end
+
+        subgraph accept["consensus.phase.accept"]
+            acc_attrs["transactions_applied = 150<br/>ledger_hash = DEF456..."]
+            acc_children["├── ledger.build<br/>└── ledger.validate"]
+        end
+
+        attrs --> open
+        open --> establish
+        establish --> accept
+    end
+
+    style round fill:#f57f17,stroke:#e65100,color:#ffffff
+    style open fill:#1565c0,stroke:#0d47a1,color:#ffffff
+    style establish fill:#2e7d32,stroke:#1b5e20,color:#ffffff
+    style accept fill:#c2185b,stroke:#880e4f,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **consensus.round (orange, root span)**: The top-level span encompassing the entire consensus round, with attributes like ledger sequence, mode, and proposer count.
+- **consensus.phase.open (blue)**: The first phase where the node waits (~3s) to collect incoming transactions before proposing.
+- **consensus.phase.establish (green)**: The negotiation phase where validators exchange proposals, resolve disputes, and converge on a transaction set. Child spans track each proposal received/sent and each dispute resolved.
+- **consensus.phase.accept (pink)**: The final phase where the agreed transaction set is applied, a new ledger is built, and the ledger is validated. Child spans cover `ledger.build` and `ledger.validate`.
+- **Arrows (open to establish to accept)**: The sequential flow through the three consensus phases. Each phase must complete before the next begins.
+
+---
+
+## 1.5 RPC Request Flow
+
+> **WS** = WebSocket
+
+RPC requests support W3C Trace Context headers for distributed tracing across services:
+
+```mermaid
+flowchart TB
+    subgraph request["rpc.request (root span)"]
+        http["HTTP Request — POST /<br/>traceparent:<br/>00-abc123...-def456...-01"]
+
+        attrs["Attributes:<br/>http.method = POST<br/>net.peer.ip = 192.168.1.100<br/>command = submit"]
+
+        subgraph enqueue["jobqueue.enqueue"]
+            job_attr["job_type = jtCLIENT_RPC"]
+        end
+
+        subgraph command["rpc.command.submit"]
+            cmd_attrs["version = 2<br/>rpc_role = user"]
+            cmd_children["├── tx.deserialize<br/>├── tx.validate_local<br/>└── tx.submit_to_network"]
+        end
+
+        response["Response: 200 OK<br/>Duration: 45ms"]
+
+        http --> attrs
+        attrs --> enqueue
+        enqueue --> command
+        command --> response
+    end
+
+    style request fill:#2e7d32,stroke:#1b5e20,color:#ffffff
+    style enqueue fill:#1565c0,stroke:#0d47a1,color:#ffffff
+    style command fill:#e65100,stroke:#bf360c,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **rpc.request (green, root span)**: The outermost span representing the full RPC request lifecycle, from HTTP receipt to response. Carries the W3C `traceparent` header for distributed tracing.
+- **HTTP Request node**: Shows the incoming POST request with its `traceparent` header and extracted attributes (method, peer IP, command name).
+- **jobqueue.enqueue (blue)**: The span covering the asynchronous handoff from the RPC thread to the JobQueue worker thread. The trace context is preserved across this async boundary.
+- **rpc.command.submit (orange)**: The span for the actual command execution, with child spans for deserialization, local validation, and network submission.
+- **Response node**: The final output with HTTP status and total duration, marking the end of the root span.
+- **Arrows (top to bottom)**: The sequential processing pipeline -- receive request, extract attributes, enqueue job, execute command, return response.
+
+---
+
+## 1.6 Key Trace Points
+
+> **TxQ** = Transaction Queue
+
+The following table identifies priority instrumentation points across the codebase:
+
+| Category        | Span Name              | File                   | Method                  | Priority |
+| --------------- | ---------------------- | ---------------------- | ----------------------- | -------- |
+| **Transaction** | `tx.receive`           | `PeerImp.cpp`          | `handleTransaction()`   | High     |
+| **Transaction** | `tx.validate`          | `NetworkOPs.cpp`       | `processTransaction()`  | High     |
+| **Transaction** | `tx.process`           | `NetworkOPs.cpp`       | `doTransactionSync()`   | High     |
+| **Transaction** | `tx.relay`             | `OverlayImpl.cpp`      | `relay()`               | Medium   |
+| **Consensus**   | `consensus.round`      | `RCLConsensus.cpp`     | `startRound()`          | High     |
+| **Consensus**   | `consensus.phase.*`    | `Consensus.h`          | `timerEntry()`          | High     |
+| **Consensus**   | `consensus.proposal.*` | `RCLConsensus.cpp`     | `peerProposal()`        | Medium   |
+| **RPC**         | `rpc.request`          | `ServerHandler.cpp`    | `onRequest()`           | High     |
+| **RPC**         | `rpc.command.*`        | `RPCHandler.cpp`       | `doCommand()`           | High     |
+| **Peer**        | `peer.connect`         | `OverlayImpl.cpp`      | `onHandoff()`           | Low      |
+| **Peer**        | `peer.message.*`       | `PeerImp.cpp`          | `onMessage()`           | Low      |
+| **Ledger**      | `ledger.acquire`       | `InboundLedgers.cpp`   | `acquire()`             | Medium   |
+| **Ledger**      | `ledger.build`         | `RCLConsensus.cpp`     | `buildLCL()`            | High     |
+| **PathFinding** | `pathfind.request`     | `PathRequest.cpp`      | `doUpdate()`            | High     |
+| **PathFinding** | `pathfind.compute`     | `Pathfinder.cpp`       | `findPaths()`           | High     |
+| **TxQ**         | `txq.enqueue`          | `TxQ.cpp`              | `apply()`               | High     |
+| **TxQ**         | `txq.apply`            | `TxQ.cpp`              | `processClosedLedger()` | High     |
+| **Fee**         | `fee.escalate`         | `LoadManager.cpp`      | `raiseLocalFee()`       | Medium   |
+| **Ledger**      | `ledger.replay`        | `LedgerReplayer.h`     | `replay()`              | Medium   |
+| **Ledger**      | `ledger.delta`         | `LedgerDeltaAcquire.h` | `processData()`         | Medium   |
+| **Validator**   | `validator.list.fetch` | `ValidatorList.cpp`    | `verify()`              | Medium   |
+| **Validator**   | `validator.manifest`   | `Manifest.cpp`         | `applyManifest()`       | Low      |
+| **Amendment**   | `amendment.vote`       | `AmendmentTable.cpp`   | `doVoting()`            | Low      |
+| **SHAMap**      | `shamap.sync`          | `SHAMap.cpp`           | `fetchRoot()`           | Medium   |
+
+---
+
+## 1.7 Instrumentation Priority
+
+> **TxQ** = Transaction Queue
+
+```mermaid
+quadrantChart
+    title Instrumentation Priority Matrix
+    x-axis Low Complexity --> High Complexity
+    y-axis Low Value --> High Value
+    quadrant-1 Implement First
+    quadrant-2 Plan Carefully
+    quadrant-3 Quick Wins
+    quadrant-4 Consider Later
+
+    RPC Tracing: [0.2, 0.92]
+    Transaction Tracing: [0.55, 0.88]
+    Consensus Tracing: [0.78, 0.82]
+    PathFinding: [0.38, 0.75]
+    TxQ and Fees: [0.25, 0.65]
+    Ledger Sync: [0.62, 0.58]
+    Peer Message Tracing: [0.35, 0.25]
+    JobQueue Tracing: [0.2, 0.48]
+    Validator Mgmt: [0.48, 0.42]
+    Amendment Tracking: [0.15, 0.32]
+    SHAMap Operations: [0.72, 0.45]
+```
+
+---
+
+## 1.8 Observable Outcomes
+
+> **TxQ** = Transaction Queue | **UNL** = Unique Node List
+
+After implementing OpenTelemetry, operators and developers will gain visibility into the following:
+
+### 1.8.1 What You Will See: Traces
+
+| Trace Type                 | Description                                                                                 | Example Query in Grafana/Tempo                  |
+| -------------------------- | ------------------------------------------------------------------------------------------- | ----------------------------------------------- |
+| **Transaction Lifecycle**  | Full journey from RPC submission through validation, relay, consensus, and ledger inclusion | `{service.name="xrpld" && tx_hash="ABC123..."}` |
+| **Cross-Node Propagation** | Transaction path across multiple xrpld nodes with timing                                    | `{relay_count > 0}`                             |
+| **Consensus Rounds**       | Complete round with all phases (open, establish, accept)                                    | `{span.name=~"consensus.round.*"}`              |
+| **RPC Request Processing** | Individual command execution with timing breakdown                                          | `{command="account_info"}`                      |
+| **Ledger Acquisition**     | Peer-to-peer ledger data requests and responses                                             | `{span.name="ledger.acquire"}`                  |
+| **PathFinding Latency**    | Path computation time and cache effectiveness for payment RPCs                              | `{span.name="pathfind.compute"}`                |
+| **TxQ Behavior**           | Queue depth, eviction patterns, fee escalation during congestion                            | `{span.name=~"txq.*"}`                          |
+| **Ledger Sync**            | Full acquisition timeline including delta and transaction fetches                           | `{span.name=~"ledger.acquire.*"}`               |
+| **Validator Health**       | UNL fetch success, manifest updates, stale list detection                                   | `{span.name=~"validator.*"}`                    |
+
+### 1.8.2 What You Will See: Metrics (Derived from Traces)
+
+| Metric                        | Description                             | Dashboard Panel             |
+| ----------------------------- | --------------------------------------- | --------------------------- |
+| **RPC Latency (p50/p95/p99)** | Response time distribution per command  | Heatmap by command          |
+| **Transaction Throughput**    | Transactions processed per second       | Time series graph           |
+| **Consensus Round Duration**  | Time to complete consensus phases       | Histogram                   |
+| **Cross-Node Latency**        | Time for transaction to reach N nodes   | Line chart with percentiles |
+| **Error Rate**                | Failed transactions/RPC calls by type   | Stacked bar chart           |
+| **PathFinding Latency**       | Path computation time per currency pair | Heatmap by currency         |
+| **TxQ Depth**                 | Queued transactions over time           | Time series with thresholds |
+| **Fee Escalation Level**      | Current fee multiplier                  | Gauge with alert thresholds |
+| **Ledger Sync Duration**      | Time to acquire missing ledgers         | Histogram                   |
+
+### 1.8.3 Concrete Dashboard Examples
+
+**Transaction Trace View (Tempo):**
+
+```
+┌────────────────────────────────────────────────────────────────────────────────┐
+│ Trace: abc123... (Transaction Submission)                    Duration: 847ms   │
+├────────────────────────────────────────────────────────────────────────────────┤
+│ ├── rpc.request [ServerHandler]                              ████░░░░░░  45ms  │
+│ │   └── rpc.command.submit [RPCHandler]                      ████░░░░░░  42ms  │
+│ │       └── tx.receive [NetworkOPs]                          ███░░░░░░░  35ms  │
+│ │           ├── tx.validate [TxQ]                            █░░░░░░░░░   8ms  │
+│ │           └── tx.relay [Overlay]                           ██░░░░░░░░  15ms  │
+│ │               ├── tx.receive [Node-B]                      █████░░░░░  52ms  │
+│ │               │   └── tx.relay [Node-B]                    ██░░░░░░░░  18ms  │
+│ │               └── tx.receive [Node-C]                      ██████░░░░  65ms  │
+│ └── consensus.round [RCLConsensus]                           ████████░░ 720ms  │
+│     ├── consensus.phase.open                                 ██░░░░░░░░ 180ms  │
+│     ├── consensus.phase.establish                            █████░░░░░ 480ms  │
+│     └── consensus.phase.accept                               █░░░░░░░░░  60ms  │
+└────────────────────────────────────────────────────────────────────────────────┘
+```
+
+**RPC Performance Dashboard Panel:**
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│ RPC Command Latency (Last 1 Hour)                           │
+├─────────────────────────────────────────────────────────────┤
+│ Command          │ p50    │ p95    │ p99    │ Errors │ Rate │
+│──────────────────┼────────┼────────┼────────┼────────┼──────│
+│ account_info     │  12ms  │  45ms  │  89ms  │  0.1%  │ 150/s│
+│ submit           │  35ms  │ 120ms  │ 250ms  │  2.3%  │  45/s│
+│ ledger           │   8ms  │  25ms  │  55ms  │  0.0%  │  80/s│
+│ tx               │  15ms  │  50ms  │ 100ms  │  0.5%  │  60/s│
+│ server_info      │   5ms  │  12ms  │  20ms  │  0.0%  │ 200/s│
+└─────────────────────────────────────────────────────────────┘
+```
+
+**Consensus Health Dashboard Panel:**
+
+```mermaid
+---
+config:
+    xyChart:
+        width: 1200
+        height: 400
+        plotReservedSpacePercent: 50
+        chartOrientation: vertical
+    themeVariables:
+        xyChart:
+            plotColorPalette: "#3498db"
+---
+xychart-beta
+    title "Consensus Round Duration (Last 24 Hours)"
+    x-axis "Time of Day (Hours)" [0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24]
+    y-axis "Duration (seconds)" 1 --> 5
+    line [2.1, 2.4, 2.8, 3.2, 3.8, 4.3, 4.5, 5.0, 4.7, 4.0, 3.2, 2.6, 2.0]
+```
+
+### 1.8.4 Operator Actionable Insights
+
+| Scenario                  | What You'll See                                                              | Action                                           |
+| ------------------------- | ---------------------------------------------------------------------------- | ------------------------------------------------ |
+| **Slow RPC**              | Span showing which phase is slow (parsing, execution, serialization)         | Optimize specific code path                      |
+| **Transaction Stuck**     | Trace stops at validation; error attribute shows reason                      | Fix transaction parameters                       |
+| **Consensus Delay**       | Phase.establish taking too long; proposer attribute shows missing validators | Investigate network connectivity                 |
+| **Memory Spike**          | Large batch of spans correlating with memory increase                        | Tune batch_size or sampling                      |
+| **Network Partition**     | Traces missing cross-node links for specific peer                            | Check peer connectivity                          |
+| **Path Computation Slow** | pathfind.compute span shows high latency; cache miss rate in attributes      | Warm the RippleLineCache, check order book depth |
+| **TxQ Full**              | txq.enqueue spans show evictions; fee.escalate spans increasing              | Monitor fee levels, alert operators              |
+| **Ledger Sync Stalled**   | ledger.acquire spans timing out; peer reliability attributes show issues     | Check peer connectivity, add trusted peers       |
+| **UNL Stale**             | validator.list.fetch spans failing; last_update attribute aging              | Verify validator site URLs, check DNS            |
+
+### 1.8.5 Developer Debugging Workflow
+
+1. **Find Transaction**: Query by `tx_hash` to get full trace
+2. **Identify Bottleneck**: Look at span durations to find slowest component
+3. **Check Attributes**: Review `validity`, `rpc_status` for errors
+4. **Correlate Logs**: Use `trace_id` to find related PerfLog entries
+5. **Compare Nodes**: Filter by `service.instance.id` to compare behavior across nodes
+
+---
+
+_Next: [Design Decisions](./02-design-decisions.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/02-design-decisions.md

@@ -0,0 +1,568 @@
+# Design Decisions
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Architecture Analysis](./01-architecture-analysis.md)
+
+---
+
+## 2.1 OpenTelemetry Components
+
+> **OTLP** = OpenTelemetry Protocol
+
+### 2.1.1 SDK Selection
+
+**Primary Choice**: OpenTelemetry C++ SDK (`opentelemetry-cpp`)
+
+| Component                               | Purpose                | Required                  |
+| --------------------------------------- | ---------------------- | ------------------------- |
+| `opentelemetry-cpp::api`                | Tracing API headers    | Yes                       |
+| `opentelemetry-cpp::sdk`                | SDK implementation     | Yes                       |
+| `opentelemetry-cpp::ext`                | Extensions (exporters) | Yes                       |
+| `opentelemetry-cpp::otlp_http_exporter` | OTLP/HTTP export       | Yes (shipped in Phase 1b) |
+| `opentelemetry-cpp::otlp_grpc_exporter` | OTLP/gRPC export       | Future (not yet wired up) |
+
+### 2.1.2 Instrumentation Strategy
+
+**Manual Instrumentation** (recommended):
+
+| Approach   | Pros                                                            | Cons                                                    |
+| ---------- | --------------------------------------------------------------- | ------------------------------------------------------- |
+| **Manual** | Precise control, optimized placement, xrpld-specific attributes | More development effort                                 |
+| **Auto**   | Less code, automatic coverage                                   | Less control, potential overhead, limited customization |
+
+---
+
+## 2.2 Exporter Configuration
+
+> **OTLP** = OpenTelemetry Protocol
+
+```mermaid
+flowchart TB
+    subgraph nodes["xrpld Nodes"]
+        node1["xrpld<br/>Node 1"]
+        node2["xrpld<br/>Node 2"]
+        node3["xrpld<br/>Node 3"]
+    end
+
+    collector["OpenTelemetry<br/>Collector<br/>(sidecar or standalone)"]
+
+    subgraph backends["Observability Backends"]
+        tempo["Tempo"]
+        elastic["Elastic<br/>APM"]
+    end
+
+    node1 -->|"OTLP/HTTP<br/>:4318"| collector
+    node2 -->|"OTLP/HTTP<br/>:4318"| collector
+    node3 -->|"OTLP/HTTP<br/>:4318"| collector
+
+    collector --> tempo
+    collector --> elastic
+
+    style nodes fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style backends fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style collector fill:#bf360c,stroke:#8c2809,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **xrpld Nodes (blue)**: The source of telemetry data. Each xrpld node exports spans via OTLP/HTTP on port 4318 (the only exporter shipped in Phase 1b).
+- **OpenTelemetry Collector (red)**: The central aggregation point that receives spans from all nodes. Can run as a sidecar (per-node) or standalone (shared). Handles batching, filtering, and routing.
+- **Observability Backends (green)**: The storage and visualization destinations. Tempo is the recommended backend for both development and production, and Elastic APM is an alternative. The Collector routes to one or more backends.
+- **Arrows (nodes to collector to backends)**: The data pipeline -- spans flow from nodes to the Collector over HTTP, then the Collector fans out to the configured backends.
+
+### 2.2.1 OTLP/HTTP (Shipped in Phase 1b)
+
+OTLP/HTTP is the only exporter wired up in Phase 1b. It is configured via
+`OtlpHttpExporterOptions` with the collector traces endpoint
+(`http://localhost:4318/v1/traces` by default) and a JSON content type
+(binary protobuf is also available).
+
+### 2.2.2 OTLP/gRPC (Future Work — Planned Upgrade)
+
+OTLP/gRPC is planned as a future upgrade from the HTTP exporter. The gRPC
+transport offers lower per-span overhead and tighter back-pressure semantics
+than HTTP/JSON, making it attractive for production deployments once the HTTP
+path is validated in earlier phases.
+
+Required to land this upgrade:
+
+1. Add `opentelemetry-cpp::otlp_grpc_exporter` to the Conan recipe (the
+   dependency already exists but is not linked in Phase 1b builds).
+2. Extend `TelemetryConfig.cpp` to parse an `exporter` key (`otlp_http`
+   default, `otlp_grpc` opt-in) and a gRPC endpoint override.
+3. In `Telemetry::start()` branch on the parsed exporter type and construct
+   either `OtlpHttpExporterFactory::Create(httpOpts)` or
+   `OtlpGrpcExporterFactory::Create(grpcOpts)` accordingly.
+4. Update the runbook and dashboards to document the alternate port and TLS
+   settings.
+
+When wired up, the gRPC path will use `OtlpGrpcExporterOptions` configured with
+the collector endpoint (host on port 4317), TLS credentials enabled, and a CA
+certificate path.
+
+Until that work lands, `OtlpGrpcExporterOptions` is **not** used by any code
+path in Phase 1b through Phase 5.
+
+---
+
+## 2.3 Span Naming Conventions
+
+> **TxQ** = Transaction Queue | **UNL** = Unique Node List | **WS** = WebSocket
+
+### 2.3.1 Naming Schema
+
+```
+<component>.<operation>[.<sub-operation>]
+```
+
+**Examples**:
+
+- `tx.receive` - Transaction received from peer
+- `consensus.phase.establish` - Consensus establish phase
+- `rpc.command.server_info` - server_info RPC command
+
+### 2.3.2 Complete Span Catalog
+
+| Span name                      | Description                             |
+| ------------------------------ | --------------------------------------- |
+| `tx.receive`                   | Transaction received from network       |
+| `tx.validate`                  | Transaction signature/format validation |
+| `tx.process`                   | Full transaction processing             |
+| `tx.relay`                     | Transaction relay to peers              |
+| `tx.apply`                     | Apply transaction to ledger             |
+| `consensus.round`              | Complete consensus round                |
+| `consensus.phase.open`         | Open phase - collecting transactions    |
+| `consensus.phase.establish`    | Establish phase - reaching agreement    |
+| `consensus.phase.accept`       | Accept phase - applying consensus       |
+| `consensus.proposal.receive`   | Receive peer proposal                   |
+| `consensus.proposal.send`      | Send our proposal                       |
+| `consensus.validation.receive` | Receive peer validation                 |
+| `consensus.validation.send`    | Send our validation                     |
+| `rpc.request`                  | HTTP/WebSocket request handling         |
+| `rpc.command.*`                | Specific RPC command (dynamic)          |
+| `peer.connect`                 | Peer connection establishment           |
+| `peer.disconnect`              | Peer disconnection                      |
+| `peer.message.send`            | Send protocol message                   |
+| `peer.message.receive`         | Receive protocol message                |
+| `ledger.acquire`               | Ledger acquisition from network         |
+| `ledger.build`                 | Build new ledger                        |
+| `ledger.validate`              | Ledger validation                       |
+| `ledger.close`                 | Close ledger                            |
+| `ledger.replay`                | Ledger replay executed                  |
+| `ledger.delta`                 | Delta-based ledger acquired             |
+| `pathfind.request`             | Path request initiated                  |
+| `pathfind.compute`             | Path computation executed               |
+| `txq.enqueue`                  | Transaction queued                      |
+| `txq.apply`                    | Queued transaction applied              |
+| `fee.escalate`                 | Fee escalation triggered                |
+| `validator.list.fetch`         | UNL list fetched                        |
+| `validator.manifest`           | Manifest update processed               |
+| `amendment.vote`               | Amendment voting executed               |
+| `shamap.sync`                  | State tree synchronization              |
+| `job.enqueue`                  | Job added to queue                      |
+| `job.execute`                  | Job execution                           |
+
+### 2.3.3 Attribute Naming Conventions
+
+Span **names** follow §2.3.1 (dotted `<component>.<operation>`). Span
+**attribute keys** follow the rules below. The constants in the `*SpanNames.h`
+headers are the single source of truth; the collector, Tempo, the Grafana
+dashboards, and the runbook all consume these exact keys, so every layer must
+agree with the code. A CI check enforces this end to end.
+
+1. **Per-span unique attribute** → bare field name, allowed when the field is
+   recorded by a single span/workflow so the span name already supplies the
+   domain (e.g. `command`, `version`, `local` on `rpc.command`).
+2. **Shared attribute (same concept on more than one span)** → ONE key, reused
+   verbatim on every span that records it; the span name tells the occurrences
+   apart, so no per-emitter prefix is added. Name it by the field's meaning: a
+   property of a domain object keeps that object's bare field name (`ledger_hash`,
+   `ledger_seq`, `tx_hash`, `peer_id`, `full_validation`); a field already
+   qualified by a sub-kind keeps that qualifier on every emitter (`proposal_trusted`
+   on both `consensus.proposal.receive` and `peer.proposal.receive`;
+   `validation_trusted` likewise). Defined once in the base `SpanNames.h`
+   `namespace attr` block and re-exported (`using`) by each domain header.
+3. **Collision qualifier** → `<domain>_<field>`, only when a bare name would
+   collide with a DIFFERENT concept in the shared spanmetrics label space or with
+   the OTel-reserved `status` key (e.g. `rpc_status`, `grpc_status`,
+   `consensus_phase`, `consensus_round`, `consensus_mode`). This disambiguates
+   distinct concepts that share a word; it is NOT used to tag the same concept
+   with its emitting workflow — that is rule 2 (one shared name).
+4. **Resource attribute** → dotted `xrpl.<subsystem>.<field>`, reserved ONLY
+   for process/network identity set once at startup (`xrpl.network.id`,
+   `xrpl.network.type`). Span attributes are never dotted in the `xrpl.` form —
+   it blurs the resource/span scope boundary and parses awkwardly in TraceQL.
+5. **Span names** use `<subsystem>[.<component>]` (dotted, per §2.3.1). Only
+   attribute _keys_ follow rules 1–4.
+
+Standard OpenTelemetry semantic-convention keys keep their canonical dotted
+form (e.g. `service.*` resource attributes, `http.*` span attributes); the
+"no dotted form" rule applies to xrpl-custom keys only.
+
+The same rules are recorded in `CONTRIBUTING.md` (the permanent home, since
+`OpenTelemetryPlan/` is removed once the rollout completes). The attribute
+examples in §2.4 below follow these rules.
+
+---
+
+## 2.4 Attribute Schema
+
+> **TxQ** = Transaction Queue | **UNL** = Unique Node List | **OTLP** = OpenTelemetry Protocol
+
+### 2.4.1 Resource Attributes (Set Once at Startup)
+
+Resource attributes identify the process and are set once at startup. They use
+the standard OpenTelemetry semantic conventions plus custom dotted `xrpl.*`
+keys (the dotted form is reserved for resource scope per §2.3.3).
+
+| Key                   | Type / value                                            | Description                    |
+| --------------------- | ------------------------------------------------------- | ------------------------------ |
+| `service.name`        | `"xrpld"`                                               | Standard `SERVICE_NAME`        |
+| `service.version`     | `build_info::getVersionString()`                        | Standard `SERVICE_VERSION`     |
+| `service.instance.id` | node public key (base58)                                | Standard `SERVICE_INSTANCE_ID` |
+| `xrpl.network.id`     | network id (e.g. 0 for mainnet)                         | Network identifier             |
+| `xrpl.network.type`   | `"mainnet"` \| `"testnet"` \| `"devnet"` \| `"unknown"` | Network kind                   |
+| `xrpl.node.type`      | `"validator"` \| `"stock"` \| `"reporting"`             | Node role                      |
+| `xrpl.node.cluster`   | cluster name                                            | Cluster name, if clustered     |
+
+### 2.4.2 Span Attributes by Category
+
+> Span attribute keys use the underscore form from §2.3.3 (shared/qualified
+> keys are `<domain>_<field>`; per-span unique keys are bare). The dotted form
+> is reserved for the resource attributes in §2.4.1 above. This catalog lists
+> the planned attribute set by category; the exact emitted key for each
+> implemented span is defined by the `*SpanNames.h` constants, which are the
+> single source of truth where the two differ.
+
+#### Transaction Attributes
+
+| Key            | Type   | Description                           |
+| -------------- | ------ | ------------------------------------- |
+| `tx_hash`      | string | Transaction hash (hex)                |
+| `tx_type`      | string | `"Payment"`, `"OfferCreate"`, etc.    |
+| `tx_account`   | string | Source account (redacted in prod)     |
+| `tx_sequence`  | int64  | Account sequence number               |
+| `tx_fee`       | int64  | Fee in drops                          |
+| `tx_result`    | string | `"tesSUCCESS"`, `"tecPATH_DRY"`, etc. |
+| `ledger_index` | int64  | Ledger containing transaction         |
+| `relay_count`  | int64  | Peers the transaction was relayed to  |
+| `suppressed`   | bool   | `true` when HashRouter dropped a dup  |
+
+#### Consensus Attributes
+
+| Key                  | Type    | Description                         |
+| -------------------- | ------- | ----------------------------------- |
+| `consensus_round`    | int64   | Round number                        |
+| `consensus_phase`    | string  | `"open"`, `"establish"`, `"accept"` |
+| `consensus_mode`     | string  | `"proposing"`, `"observing"`, etc.  |
+| `proposers`          | int64   | Number of proposers                 |
+| `prev_ledger_prefix` | string  | Previous ledger hash prefix         |
+| `ledger_seq`         | int64   | Ledger sequence                     |
+| `tx_count`           | int64   | Transactions in consensus set       |
+| `round_time_ms`      | float64 | Round duration                      |
+
+#### RPC Attributes
+
+| Key           | Type    | Description                                                                   |
+| ------------- | ------- | ----------------------------------------------------------------------------- |
+| `command`     | string  | Command name (per-span unique on `rpc.command`)                               |
+| `version`     | int64   | API version                                                                   |
+| `rpc_role`    | string  | `"admin"` or `"user"` (qualified — `role` is generic)                         |
+| `params`      | string  | Sanitized parameters (optional)                                               |
+| `rpc_status`  | string  | Response status: `success` \| `error` (qualified — `status` is OTel-reserved) |
+| `duration_ms` | float64 | Request duration in milliseconds                                              |
+
+#### Peer & Message Attributes
+
+| Key                  | Type    | Description                |
+| -------------------- | ------- | -------------------------- |
+| `peer_id`            | string  | Peer public key (base58)   |
+| `peer_address`       | string  | IP:port                    |
+| `peer_latency_ms`    | float64 | Measured latency           |
+| `peer_cluster`       | string  | Cluster name if clustered  |
+| `message_type`       | string  | Protocol message type name |
+| `message_size_bytes` | int64   | Message size               |
+| `message_compressed` | bool    | Whether compressed         |
+
+#### Ledger & Job Attributes
+
+| Key               | Type    | Description           |
+| ----------------- | ------- | --------------------- |
+| `ledger_hash`     | string  | Ledger hash           |
+| `ledger_index`    | int64   | Ledger sequence/index |
+| `close_time`      | int64   | Close time (epoch)    |
+| `ledger_tx_count` | int64   | Transaction count     |
+| `job_type`        | string  | Job type name         |
+| `job_queue_ms`    | float64 | Time spent in queue   |
+| `job_worker`      | int64   | Worker thread ID      |
+
+#### PathFinding Attributes
+
+| Key                        | Type   | Description               |
+| -------------------------- | ------ | ------------------------- |
+| `pathfind_source_currency` | string | Source currency code      |
+| `pathfind_dest_currency`   | string | Destination currency code |
+| `pathfind_path_count`      | int64  | Number of paths found     |
+| `pathfind_cache_hit`       | bool   | RippleLineCache hit       |
+
+#### TxQ Attributes
+
+| Key                   | Type   | Description                 |
+| --------------------- | ------ | --------------------------- |
+| `txq_queue_depth`     | int64  | Current queue depth         |
+| `txq_fee_level`       | int64  | Fee level of transaction    |
+| `txq_eviction_reason` | string | Why transaction was evicted |
+
+#### Fee Attributes
+
+| Key                    | Type  | Description               |
+| ---------------------- | ----- | ------------------------- |
+| `fee_load_factor`      | int64 | Current load factor       |
+| `fee_escalation_level` | int64 | Fee escalation multiplier |
+
+#### Validator Attributes
+
+| Key                      | Type  | Description               |
+| ------------------------ | ----- | ------------------------- |
+| `validator_list_size`    | int64 | UNL size                  |
+| `validator_list_age_sec` | int64 | Seconds since last update |
+
+#### Amendment Attributes
+
+| Key                | Type   | Description                            |
+| ------------------ | ------ | -------------------------------------- |
+| `amendment_name`   | string | Amendment name                         |
+| `amendment_status` | string | `"enabled"`, `"vetoed"`, `"supported"` |
+
+#### SHAMap Attributes
+
+| Key                    | Type    | Description                                   |
+| ---------------------- | ------- | --------------------------------------------- |
+| `shamap_type`          | string  | `"transaction"`, `"state"`, `"account_state"` |
+| `shamap_missing_nodes` | int64   | Number of missing nodes during sync           |
+| `shamap_duration_ms`   | float64 | Sync duration                                 |
+
+### 2.4.3 Data Collection Summary
+
+The following table summarizes what data is collected by category:
+
+| Category        | Attributes Collected                                                                              | Purpose                      |
+| --------------- | ------------------------------------------------------------------------------------------------- | ---------------------------- |
+| **Transaction** | `tx_hash`, `tx_type`, `tx_result`, `tx_fee`, `ledger_index`                                       | Trace transaction lifecycle  |
+| **Consensus**   | `consensus_round`, `consensus_phase`, `consensus_mode`, `proposers`, `round_time_ms`              | Analyze consensus timing     |
+| **RPC**         | `command`, `version`, `rpc_status`, `duration_ms`                                                 | Monitor RPC performance      |
+| **Peer**        | `peer_id` (public key), `peer_latency_ms`, `message_type`, `message_size_bytes`                   | Network topology analysis    |
+| **Ledger**      | `ledger_hash`, `ledger_index`, `close_time`, `ledger_tx_count`                                    | Ledger progression tracking  |
+| **Job**         | `job_type`, `job_queue_ms`, `job_worker`                                                          | JobQueue performance         |
+| **PathFinding** | `pathfind_source_currency`, `pathfind_dest_currency`, `pathfind_path_count`, `pathfind_cache_hit` | Payment path analysis        |
+| **TxQ**         | `txq_queue_depth`, `txq_fee_level`, `txq_eviction_reason`                                         | Queue depth and fee tracking |
+| **Fee**         | `fee_load_factor`, `fee_escalation_level`                                                         | Fee escalation monitoring    |
+| **Validator**   | `validator_list_size`, `validator_list_age_sec`                                                   | UNL health monitoring        |
+| **Amendment**   | `amendment_name`, `amendment_status`                                                              | Protocol upgrade tracking    |
+| **SHAMap**      | `shamap_type`, `shamap_missing_nodes`, `shamap_duration_ms`                                       | State tree sync performance  |
+
+### 2.4.4 Privacy & Sensitive Data Policy
+
+> **PII** = Personally Identifiable Information
+
+OpenTelemetry instrumentation is designed to collect **operational metadata only**, never sensitive content.
+
+#### Data NOT Collected
+
+The following data is explicitly **excluded** from telemetry collection:
+
+| Excluded Data           | Reason                                    |
+| ----------------------- | ----------------------------------------- |
+| **Private Keys**        | Never exposed; not relevant to tracing    |
+| **Account Balances**    | Financial data; privacy sensitive         |
+| **Transaction Amounts** | Financial data; privacy sensitive         |
+| **Raw TX Payloads**     | May contain sensitive memo/data fields    |
+| **Personal Data**       | No PII collected                          |
+| **IP Addresses**        | Configurable; excluded by default in prod |
+
+#### Privacy Protection Mechanisms
+
+| Mechanism                     | Description                                                                                                                             |
+| ----------------------------- | --------------------------------------------------------------------------------------------------------------------------------------- |
+| **Account Hashing**           | `tx_account` is hashed at collector level before storage                                                                                |
+| **Configurable Redaction**    | Sensitive fields can be excluded via `[telemetry]` config section                                                                       |
+| **Collector Tail Sampling**   | xrpld head sampling is fixed at 1.0 (every span emitted); the collector retains ~10% of non-error traces, reducing stored data exposure |
+| **Local Control**             | Node operators have full control over what gets exported                                                                                |
+| **No Raw Payloads**           | Transaction content is never recorded, only metadata (hash, type, result)                                                               |
+| **Collector-Level Filtering** | Additional redaction/hashing can be configured at OTel Collector                                                                        |
+
+#### Collector-Level Data Protection
+
+The OpenTelemetry Collector can be configured (via an `attributes` processor)
+to hash or redact sensitive attributes before export — for example, hashing
+`tx_account`, deleting `peer_address` to drop IP addresses, and deleting
+`params` to redact request parameters.
+
+#### Configuration Options for Privacy
+
+In `xrpld.cfg`, operators control data collection granularity through the
+`[telemetry]` section. Besides `enabled`, per-component toggles
+(`trace_transactions`, `trace_consensus`, `trace_rpc`, `trace_peer` — the last
+often disabled due to high volume) select which spans are emitted, and
+redaction flags (`redact_account` to hash account addresses, `redact_peer_address`
+to remove peer IP addresses) control SDK-level redaction before export.
+
+> **Note**: The `redact_account` configuration in `xrpld.cfg` controls SDK-level redaction before export, while collector-level filtering (see [Collector-Level Data Protection](#collector-level-data-protection) above) provides an additional defense-in-depth layer. Both can operate independently.
+
+> **Key Principle**: Telemetry collects **operational metadata** (timing, counts, hashes) — never **sensitive content** (keys, balances, amounts, raw payloads).
+
+---
+
+## 2.5 Context Propagation Design
+
+> **WS** = WebSocket
+
+### 2.5.1 Propagation Boundaries
+
+```mermaid
+flowchart TB
+    subgraph http["HTTP/WebSocket (RPC)"]
+        w3c["W3C Trace Context Headers:<br/>traceparent:<br/>00-trace_id-span_id-flags<br/>tracestate: xrpld=..."]
+    end
+
+    subgraph protobuf["Protocol Buffers (P2P)"]
+        proto["message TraceContext {<br/>  bytes trace_id = 1;  // 16 bytes<br/>  bytes span_id = 2;   // 8 bytes<br/>  uint32 trace_flags = 3;<br/>  string trace_state = 4;<br/>}"]
+    end
+
+    subgraph jobqueue["JobQueue (Internal Async)"]
+        job["Context captured at job creation,<br/>restored at execution<br/><br/>class Job {<br/>  otel::context::Context<br/>    traceContext_;<br/>};"]
+    end
+
+    style http fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style protobuf fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style jobqueue fill:#bf360c,stroke:#8c2809,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **HTTP/WebSocket - RPC (blue)**: For client-facing RPC requests, trace context is propagated using the W3C `traceparent` header. This is the standard approach and works with any OTel-compatible client.
+- **Protocol Buffers - P2P (green)**: For peer-to-peer messages between xrpld nodes, trace context is embedded as a protobuf `TraceContext` message carrying trace_id, span_id, flags, and optional trace_state.
+- **JobQueue - Internal Async (red)**: For asynchronous work within a single node, the OTel context is captured when a job is created and restored when the job executes on a worker thread. This bridges the async gap so spans remain linked.
+
+---
+
+## 2.6 Integration with Existing Observability
+
+> **OTLP** = OpenTelemetry Protocol | **WS** = WebSocket
+
+### 2.6.1 Existing Frameworks Comparison
+
+xrpld already has two observability mechanisms. OpenTelemetry complements (not replaces) them:
+
+| Aspect                | PerfLog                       | Beast Insight (StatsD)       | OpenTelemetry             |
+| --------------------- | ----------------------------- | ---------------------------- | ------------------------- |
+| **Type**              | Logging                       | Metrics                      | Distributed Tracing       |
+| **Data**              | JSON log entries              | Counters, gauges, histograms | Spans with context        |
+| **Scope**             | Single node                   | Single node                  | **Cross-node**            |
+| **Output**            | `perf.log` file               | StatsD server                | OTLP Collector            |
+| **Question answered** | "What happened on this node?" | "How many? How fast?"        | "What was the journey?"   |
+| **Correlation**       | By timestamp                  | By metric name               | By `trace_id`             |
+| **Overhead**          | Low (file I/O)                | Low (UDP packets)            | Low-Medium (configurable) |
+
+### 2.6.2 What Each Framework Does Best
+
+#### PerfLog
+
+- **Purpose**: Detailed local event logging for RPC and job execution
+- **Strengths**:
+  - Rich JSON output with timing data
+  - Already integrated in RPC handlers
+  - File-based, no external dependencies
+- **Limitations**:
+  - Single-node only (no cross-node correlation)
+  - No parent-child relationships between events
+  - Manual log parsing required
+
+A PerfLog entry is a JSON object with fields such as `time`, `method`,
+`duration_us`, and `result`.
+
+#### Beast Insight (StatsD)
+
+- **Purpose**: Real-time metrics for monitoring dashboards
+- **Strengths**:
+  - Aggregated metrics (counters, gauges, histograms)
+  - Low overhead (UDP, fire-and-forget)
+  - Good for alerting thresholds
+- **Limitations**:
+  - No request-level detail
+  - No causal relationships
+  - Single-node perspective
+
+In xrpld, Beast Insight is used through `increment` (counters), `gauge`
+(point-in-time values), and `timing` (durations) calls.
+
+#### OpenTelemetry (NEW)
+
+- **Purpose**: Distributed request tracing across nodes
+- **Strengths**:
+  - **Cross-node correlation** via `trace_id`
+  - Parent-child span relationships
+  - Rich attributes per span
+  - Industry standard (CNCF)
+- **Limitations**:
+  - Requires collector infrastructure
+  - Higher complexity than logging
+
+A span is created via `startSpan` (e.g. `"tx.relay"`), annotated with
+attributes such as `tx_hash` and `peer_id`, and is automatically linked to its
+parent through the active context.
+
+### 2.6.3 When to Use Each
+
+| Scenario                                | PerfLog    | StatsD | OpenTelemetry |
+| --------------------------------------- | ---------- | ------ | ------------- |
+| "How many TXs per second?"              | ❌         | ✅     | ✅            |
+| "What's the p99 RPC latency?"           | ❌         | ✅     | ✅            |
+| "Why was this specific TX slow?"        | ⚠️ partial | ❌     | ✅            |
+| "Which node delayed consensus?"         | ❌         | ❌     | ✅            |
+| "What happened on node X at time T?"    | ✅         | ❌     | ✅            |
+| "Show me the TX journey across 5 nodes" | ❌         | ❌     | ✅            |
+
+### 2.6.4 Coexistence Strategy
+
+```mermaid
+flowchart TB
+    subgraph xrpld["xrpld Process"]
+        perflog["PerfLog<br/>(JSON to file)"]
+        insight["Beast Insight<br/>(StatsD)"]
+        otel["OpenTelemetry<br/>(Tracing)"]
+    end
+
+    perflog --> perffile["perf.log"]
+    insight --> statsd["StatsD Server"]
+    otel --> collector["OTLP Collector"]
+
+    perffile --> grafana["Grafana<br/>(Unified UI)"]
+    statsd --> grafana
+    collector --> grafana
+
+    style xrpld fill:#212121,stroke:#0a0a0a,color:#ffffff
+    style grafana fill:#bf360c,stroke:#8c2809,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **xrpld Process (dark gray)**: The single xrpld node running all three observability frameworks side by side. Each framework operates independently with no interference.
+- **PerfLog to perf.log**: PerfLog writes JSON-formatted event logs to a local file. Grafana can ingest these via Loki or a file-based datasource.
+- **Beast Insight to StatsD Server**: Insight sends aggregated metrics (counters, gauges) over UDP to a StatsD server. Grafana reads from StatsD-compatible backends like Graphite or Prometheus (via StatsD exporter).
+- **OpenTelemetry to OTLP Collector**: OTel exports spans over OTLP/HTTP to a Collector, which then forwards to a trace backend (Tempo). (OTLP/gRPC is future work — §2.2.2.)
+- **Grafana (red, unified UI)**: All three data streams converge in Grafana, enabling operators to correlate logs, metrics, and traces in a single dashboard.
+
+### 2.6.5 Correlation with PerfLog
+
+Trace IDs can be correlated with existing PerfLog entries for comprehensive
+debugging. The design is for `RPCHandler.cpp` to start an `rpc.command.<method>`
+span alongside the existing PerfLog `rpcStart`/`rpcFinish`/`rpcError` calls,
+extract the span's `trace_id` (when valid), and eventually stamp it onto the
+PerfLog entry (a planned `setTraceId` hook) so logs and traces share a key. The
+span status is set to OK on success or to error (recording the exception) on
+failure.
+
+---
+
+_Previous: [Architecture Analysis](./01-architecture-analysis.md)_ | _Next: [Implementation Strategy](./03-implementation-strategy.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/03-implementation-strategy.md

@@ -0,0 +1,415 @@
+# Implementation Strategy
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Configuration Reference](./05-configuration-reference.md)
+
+---
+
+## 3.1 Directory Structure
+
+The telemetry implementation follows xrpld's existing code organization pattern:
+
+```
+include/xrpl/
+├── telemetry/
+│   ├── Telemetry.h              # Main telemetry interface
+│   ├── TelemetryConfig.h        # Configuration structures
+│   ├── TraceContext.h           # Context propagation utilities
+│   ├── SpanGuard.h              # RAII span management
+│   └── SpanAttributes.h         # Attribute helper functions
+
+src/libxrpl/
+├── telemetry/
+│   ├── Telemetry.cpp            # Implementation
+│   ├── TelemetryConfig.cpp      # Config parsing
+│   ├── TraceContext.cpp         # Context serialization
+│   └── NullTelemetry.cpp        # No-op implementation
+
+src/xrpld/
+├── telemetry/
+│   ├── TracingInstrumentation.h # Instrumentation macros
+│   └── TracingInstrumentation.cpp
+```
+
+---
+
+## 3.2 Implementation Approach
+
+<div align="center">
+
+```mermaid
+%%{init: {'flowchart': {'nodeSpacing': 20, 'rankSpacing': 30}}}%%
+flowchart TB
+    subgraph phase1["Phase 1: Core"]
+        direction LR
+        sdk["SDK Integration"] ~~~ interface["Telemetry Interface"] ~~~ config["Configuration"]
+    end
+
+    subgraph phase2["Phase 2: RPC"]
+        direction LR
+        http["HTTP Context"] ~~~ rpc["RPC Handlers"]
+    end
+
+    subgraph phase3["Phase 3: P2P"]
+        direction LR
+        proto["Protobuf Context"] ~~~ tx["Transaction Relay"]
+    end
+
+    subgraph phase4["Phase 4: Consensus"]
+        direction LR
+        consensus["Consensus Rounds"] ~~~ proposals["Proposals"]
+    end
+
+    phase1 --> phase2 --> phase3 --> phase4
+
+    style phase1 fill:#1565c0,stroke:#0d47a1,color:#ffffff
+    style phase2 fill:#2e7d32,stroke:#1b5e20,color:#ffffff
+    style phase3 fill:#e65100,stroke:#bf360c,color:#ffffff
+    style phase4 fill:#c2185b,stroke:#880e4f,color:#ffffff
+```
+
+</div>
+
+### Key Principles
+
+1. **Minimal Intrusion**: Instrumentation should not alter existing control flow
+2. **Zero-Cost When Disabled**: Use compile-time flags and no-op implementations
+3. **Backward Compatibility**: Protocol Buffer extensions use high field numbers
+4. **Graceful Degradation**: Tracing failures must not affect node operation
+
+---
+
+## 3.3 Performance Overhead Summary
+
+> **OTLP** = OpenTelemetry Protocol
+
+| Metric        | Overhead   | Notes                                            |
+| ------------- | ---------- | ------------------------------------------------ |
+| CPU           | 1-3%       | Of per-transaction CPU cost (~200μs baseline)    |
+| Memory        | ~10 MB     | SDK statics + batch buffer + worker thread stack |
+| Network       | 10-50 KB/s | Compressed OTLP export to collector              |
+| Latency (p99) | <2%        | With proper sampling configuration               |
+
+---
+
+## 3.4 Detailed CPU Overhead Analysis
+
+### 3.4.1 Per-Operation Costs
+
+> **Note on hardware assumptions**: The costs below are based on the official OTel C++ SDK CI benchmarks
+> (969 runs on GitHub Actions 2-core shared runners). On production server hardware (3+ GHz Xeon),
+> expect costs at the **lower end** of each range (~30-50% improvement over CI hardware).
+
+| Operation             | Time (ns) | Frequency              | Impact     |
+| --------------------- | --------- | ---------------------- | ---------- |
+| Span creation         | 500-1000  | Every traced operation | Low        |
+| Span end              | 100-200   | Every traced operation | Low        |
+| SetAttribute (string) | 80-120    | 3-5 per span           | Low        |
+| SetAttribute (int)    | 40-60     | 2-3 per span           | Negligible |
+| AddEvent              | 100-200   | 0-2 per span           | Low        |
+| Context injection     | 150-250   | Per outgoing message   | Low        |
+| Context extraction    | 100-180   | Per incoming message   | Low        |
+| GetCurrent context    | 10-20     | Thread-local access    | Negligible |
+
+**Source**: Span creation based on OTel C++ SDK `BM_SpanCreation` benchmark (AlwaysOnSampler +
+SimpleSpanProcessor + InMemoryExporter), median ~1,000 ns on CI hardware. AddEvent includes
+timestamp read + string copy + vector push + mutex acquisition. Context injection/extraction
+confirmed by `BM_SpanCreationWithScope` benchmark delta (~160 ns).
+
+### 3.4.2 Transaction Processing Overhead
+
+<div align="center">
+
+```mermaid
+%%{init: {'pie': {'textPosition': 0.75}}}%%
+pie showData
+    "tx.receive (1400ns)" : 1400
+    "tx.validate (1200ns)" : 1200
+    "tx.relay (1200ns)" : 1200
+    "Context inject (200ns)" : 200
+```
+
+**Transaction Tracing Overhead (~4.0μs total)**
+
+</div>
+
+**Overhead percentage**: 4.0 μs / 200 μs (avg tx processing) = **~2.0%**
+
+> **Breakdown**: Each span (tx.receive, tx.validate, tx.relay) costs ~1,000 ns for creation plus
+> ~200-400 ns for 3-5 attribute sets. Context injection is ~200 ns (confirmed by benchmarks).
+> On production hardware, expect ~2.6 μs total (~1.3% overhead) due to faster span creation (~500-600 ns).
+
+### 3.4.3 Consensus Round Overhead
+
+| Operation              | Count | Cost (ns) | Total      |
+| ---------------------- | ----- | --------- | ---------- |
+| consensus.round span   | 1     | ~1200     | ~1.2 μs    |
+| consensus.phase spans  | 3     | ~1100     | ~3.3 μs    |
+| proposal.receive spans | ~20   | ~1100     | ~22 μs     |
+| proposal.send spans    | ~3    | ~1100     | ~3.3 μs    |
+| Context operations     | ~30   | ~200      | ~6 μs      |
+| **TOTAL**              |       |           | **~36 μs** |
+
+> **Why higher**: Each span costs ~1,000 ns creation + ~100-200 ns for 1-2 attributes, totaling ~1,100-1,200 ns.
+> Context operations remain ~200 ns (confirmed by benchmarks). On production hardware, expect ~24 μs total.
+
+**Overhead percentage**: 36 μs / 3s (typical round) = **~0.001%** (negligible)
+
+### 3.4.4 RPC Request Overhead
+
+| Operation        | Cost (ns)    |
+| ---------------- | ------------ |
+| rpc.request span | ~1200        |
+| rpc.command span | ~1100        |
+| Context extract  | ~250         |
+| Context inject   | ~200         |
+| **TOTAL**        | **~2.75 μs** |
+
+> **Why higher**: Each span costs ~1,000 ns creation + ~100-200 ns for attributes (command name,
+> version, role). Context extract/inject costs are confirmed by OTel C++ benchmarks.
+
+- Fast RPC (1ms): 2.75 μs / 1ms = **~0.275%**
+- Slow RPC (100ms): 2.75 μs / 100ms = **~0.003%**
+
+---
+
+## 3.5 Memory Overhead Analysis
+
+> **OTLP** = OpenTelemetry Protocol
+
+### 3.5.1 Static Memory
+
+| Component                            | Size        | Allocated  |
+| ------------------------------------ | ----------- | ---------- |
+| TracerProvider singleton             | ~64 KB      | At startup |
+| BatchSpanProcessor (circular buffer) | ~16 KB      | At startup |
+| BatchSpanProcessor (worker thread)   | ~8 MB       | At startup |
+| OTLP/HTTP exporter (client init)     | ~64 KB      | At startup |
+| Propagator registry                  | ~8 KB       | At startup |
+| **Total static**                     | **~8.1 MB** |            |
+
+> **Why higher than earlier estimate**: The BatchSpanProcessor's circular buffer itself is only ~16 KB
+> (2049 x 8-byte `AtomicUniquePtr` entries), but it spawns a dedicated worker thread whose default
+> stack size on Linux is ~8 MB. The OTLP/HTTP exporter allocates a small client and TLS
+> initialization buffer. The worker thread stack dominates the static footprint.
+
+### 3.5.2 Dynamic Memory
+
+| Component            | Size per unit  | Max units  | Peak            |
+| -------------------- | -------------- | ---------- | --------------- |
+| Active span          | ~500-800 bytes | 1000       | ~500-800 KB     |
+| Queued span (export) | ~500 bytes     | 2048       | ~1 MB           |
+| Attribute storage    | ~80 bytes      | 5 per span | Included        |
+| Context storage      | ~64 bytes      | Per thread | ~6.4 KB         |
+| **Total dynamic**    |                |            | **~1.5-1.8 MB** |
+
+> **Why active spans are larger**: An active `Span` object includes the wrapper (~88 bytes: shared_ptr,
+> mutex, unique_ptr to Recordable) plus `SpanData` (~250 bytes: SpanContext, timestamps, name, status,
+> empty containers) plus attribute storage (~200-500 bytes for 3-5 string attributes in a `std::map`).
+> Source: `sdk/src/trace/span.h` and `sdk/include/opentelemetry/sdk/trace/span_data.h`.
+> Queued spans release the wrapper, keeping only `SpanData` + attributes (~500 bytes).
+
+### 3.5.3 Memory Growth Characteristics
+
+```mermaid
+---
+config:
+    xyChart:
+        width: 700
+        height: 400
+---
+xychart-beta
+    title "Memory Usage vs Span Rate (bounded by queue limit)"
+    x-axis "Spans/second" [0, 200, 400, 600, 800, 1000]
+    y-axis "Memory (MB)" 0 --> 12
+    line [8.5, 9.2, 9.6, 9.9, 10.0, 10.0]
+```
+
+**Notes**:
+
+- Memory increases with span rate but **plateaus at queue capacity** (default 2048 spans)
+- Batch export prevents unbounded growth
+- At queue limit, oldest spans are dropped (not blocked)
+- Maximum memory is bounded: ~8.3 MB static (dominated by worker thread stack) + 2048 queued spans x ~500 bytes (~1 MB) + active spans (~0.8 MB) ≈ **~10 MB ceiling**
+- The worker thread stack (~8 MB) is virtual memory; actual RSS depends on stack usage (typically much less)
+
+> **Measured outcome**: A perf-iac comparison (telemetry compiled-in + enabled vs compiled-out,
+> 9 nodes — validators and client-handlers — under sustained payment load) recorded **no measurable
+> RSS increase over the telemetry-off baseline** (~15 GiB mean / ~18–19 GiB peak on both sides),
+> with no OOM, no swap, and no leak across the run. The ~10 MB ceiling above is therefore a
+> provisioning safety margin (dominated by virtual thread-stack address space), not an expected
+> resident-memory increase. Steady-state cost shows up as throughput (~3–4% at head sampling 1.0),
+> not memory.
+
+### 3.5.4 Performance Data Sources
+
+The overhead estimates in Sections 3.3-3.5 are derived from the following sources:
+
+| Source                                           | What it covers                                        | URL                                                                                                                                        |
+| ------------------------------------------------ | ----------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
+| OTel C++ SDK CI benchmarks (969 runs)            | Span creation, context activation, sampler overhead   | [Benchmark Dashboard](https://open-telemetry.github.io/opentelemetry-cpp/benchmarks/)                                                      |
+| `api/test/trace/span_benchmark.cc`               | API-level span creation (~22 ns no-op)                | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/api/test/trace/span_benchmark.cc)                                   |
+| `sdk/test/trace/sampler_benchmark.cc`            | SDK span creation with samplers (~1,000 ns AlwaysOn)  | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/sdk/test/trace/sampler_benchmark.cc)                                |
+| `sdk/include/.../span_data.h`                    | SpanData memory layout (~250 bytes base)              | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/sdk/include/opentelemetry/sdk/trace/span_data.h)                    |
+| `sdk/src/trace/span.h`                           | Span wrapper memory layout (~88 bytes)                | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/sdk/src/trace/span.h)                                               |
+| `sdk/include/.../batch_span_processor_options.h` | Default queue size (2048), batch size (512)           | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/sdk/include/opentelemetry/sdk/trace/batch_span_processor_options.h) |
+| `sdk/include/.../circular_buffer.h`              | CircularBuffer implementation (AtomicUniquePtr array) | [Source](https://github.com/open-telemetry/opentelemetry-cpp/blob/main/sdk/include/opentelemetry/sdk/common/circular_buffer.h)             |
+| OTLP proto definition                            | Serialized span size estimation                       | [Proto](https://github.com/open-telemetry/opentelemetry-proto/blob/main/opentelemetry/proto/trace/v1/trace.proto)                          |
+
+---
+
+## 3.6 Network Overhead Analysis
+
+### 3.6.1 Export Bandwidth
+
+> **Bytes per span**: Estimates use ~500 bytes/span (conservative upper bound). OTLP protobuf analysis
+> shows a typical span with 3-5 string attributes serializes to ~200-300 bytes raw; with gzip
+> compression (~60-70% of raw) and batching (amortized headers), ~350 bytes/span is more realistic.
+> The table uses the conservative estimate for capacity planning.
+
+| Sampling Rate | Spans/sec | Bandwidth | Notes            |
+| ------------- | --------- | --------- | ---------------- |
+| 100%          | ~500      | ~250 KB/s | Development only |
+| 10%           | ~50       | ~25 KB/s  | Staging          |
+| 1%            | ~5        | ~2.5 KB/s | Production       |
+| Error-only    | ~1        | ~0.5 KB/s | Minimal overhead |
+
+### 3.6.2 Trace Context Propagation
+
+| Message Type           | Context Size | Messages/sec | Overhead    |
+| ---------------------- | ------------ | ------------ | ----------- |
+| TMTransaction          | 25 bytes     | ~100         | ~2.5 KB/s   |
+| TMProposeSet           | 25 bytes     | ~10          | ~250 B/s    |
+| TMValidation           | 25 bytes     | ~50          | ~1.25 KB/s  |
+| **Total P2P overhead** |              |              | **~4 KB/s** |
+
+---
+
+## 3.7 Optimization Strategies
+
+### 3.7.1 Sampling Strategies
+
+#### Tail Sampling
+
+```mermaid
+flowchart TD
+    trace["New Trace"]
+
+    trace --> errors{"Is Error?"}
+    errors -->|Yes| sample["SAMPLE"]
+    errors -->|No| consensus{"Is Consensus?"}
+
+    consensus -->|Yes| sample
+    consensus -->|No| slow{"Is Slow?"}
+
+    slow -->|Yes| sample
+    slow -->|No| prob{"Random < 10%?"}
+
+    prob -->|Yes| sample
+    prob -->|No| drop["DROP"]
+
+    style sample fill:#4caf50,stroke:#388e3c,color:#fff
+    style drop fill:#f44336,stroke:#c62828,color:#fff
+```
+
+### 3.7.2 Batch Tuning Recommendations
+
+| Environment        | Batch Size | Batch Delay | Max Queue |
+| ------------------ | ---------- | ----------- | --------- |
+| Low-latency        | 128        | 1000ms      | 512       |
+| High-throughput    | 1024       | 10000ms     | 8192      |
+| Memory-constrained | 256        | 2000ms      | 512       |
+
+### 3.7.3 Conditional Instrumentation
+
+Instrumentation is gated on two levels. A compile-time feature flag (`XRPL_ENABLE_TELEMETRY`) reduces the trace macros to no-ops when telemetry is built out, so disabled builds carry zero cost. At runtime, per-component guards (e.g. `shouldTracePeer()`) skip span creation for components whose tracing is turned off, incurring no overhead beyond a single boolean check.
+
+---
+
+## 3.8 Links to Detailed Documentation
+
+- **[Configuration Reference](./05-configuration-reference.md)**: Configuration options and collector setup
+- **[Implementation Phases](./06-implementation-phases.md)**: Detailed timeline and milestones
+
+---
+
+## 3.9 Code Intrusiveness Assessment
+
+> **TxQ** = Transaction Queue
+
+This section provides a detailed assessment of how intrusive the OpenTelemetry integration is to the existing xrpld codebase.
+
+### 3.9.3 Risk Assessment by Component
+
+<div align="center">
+
+**Do First** ↖ ↗ **Plan Carefully**
+
+```mermaid
+quadrantChart
+    title Code Intrusiveness Risk Matrix
+    x-axis Low Risk --> High Risk
+    y-axis Low Value --> High Value
+
+    RPC Tracing: [0.2, 0.55]
+    Transaction Relay: [0.55, 0.85]
+    Consensus Tracing: [0.75, 0.92]
+    Peer Message Tracing: [0.85, 0.35]
+    JobQueue Context: [0.3, 0.42]
+    Ledger Acquisition: [0.48, 0.65]
+    PathFinding: [0.38, 0.72]
+    TxQ and Fees: [0.25, 0.62]
+    Validator Mgmt: [0.15, 0.35]
+```
+
+**Optional** ↙ ↘ **Avoid**
+
+</div>
+
+#### Risk Level Definitions
+
+| Risk Level | Definition                                                       | Mitigation                         |
+| ---------- | ---------------------------------------------------------------- | ---------------------------------- |
+| **Low**    | Additive changes only; no modification to existing logic         | Standard code review               |
+| **Medium** | Minor modifications to existing functions; clear boundaries      | Comprehensive unit tests           |
+| **High**   | Changes to core logic or data structures; potential side effects | Integration tests + staged rollout |
+
+### 3.9.4 Architectural Impact Assessment
+
+| Aspect               | Impact  | Justification                                                                    |
+| -------------------- | ------- | -------------------------------------------------------------------------------- |
+| **Data Flow**        | Minimal | Read-only instrumentation; no modification to consensus or transaction data flow |
+| **Threading Model**  | Minimal | Context propagation uses thread-local storage (standard OTel pattern)            |
+| **Memory Model**     | Low     | Bounded queues prevent unbounded growth; RAII ensures cleanup                    |
+| **Network Protocol** | Low     | Optional fields in protobuf (high field numbers); backward compatible            |
+| **Configuration**    | None    | New config section; existing configs unaffected                                  |
+| **Build System**     | Low     | Optional CMake flag; builds work without OpenTelemetry                           |
+| **Dependencies**     | Low     | OpenTelemetry SDK is optional; null implementation when disabled                 |
+
+### 3.9.5 Backward Compatibility
+
+| Compatibility   | Status  | Notes                                                 |
+| --------------- | ------- | ----------------------------------------------------- |
+| **Config File** | ✅ Full | New `[telemetry]` section is optional                 |
+| **Protocol**    | ✅ Full | Optional protobuf fields with high field numbers      |
+| **Build**       | ✅ Full | `XRPL_ENABLE_TELEMETRY=OFF` produces identical binary |
+| **Runtime**     | ✅ Full | `enabled=0` produces zero overhead                    |
+| **API**         | ✅ Full | No changes to public RPC or P2P APIs                  |
+
+### 3.9.6 Rollback Strategy
+
+If issues are discovered after deployment:
+
+1. **Immediate**: Set `enabled=0` in config and restart (zero code change)
+2. **Quick**: Rebuild with `XRPL_ENABLE_TELEMETRY=OFF`
+3. **Complete**: Revert telemetry commits (clean separation makes this easy)
+
+### 3.9.7 Code Change Examples
+
+**Minimal RPC Instrumentation (Low Intrusiveness):** Instrumenting an RPC handler adds roughly 3-4 lines: one macro to start the span and one or two `setAttribute` calls (command name, status). The span ends automatically via RAII, so the existing control flow — process the request, send the result — is untouched.
+
+**Consensus Instrumentation (Medium Intrusiveness):** Consensus is slightly more intrusive because child spans in later phase transitions need the round's context. Beyond the span-start and attribute macros, this requires storing the active context in a new member variable (`currentRoundContext_`) at round start. The existing round logic itself remains unchanged.
+
+---
+
+_Previous: [Design Decisions](./02-design-decisions.md)_ | _Next: [Configuration Reference](./05-configuration-reference.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/05-configuration-reference.md

@@ -0,0 +1,265 @@
+# Configuration Reference
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Implementation Phases](./06-implementation-phases.md)
+
+---
+
+## 5.1 xrpld Configuration
+
+> **OTLP** = OpenTelemetry Protocol | **TxQ** = Transaction Queue
+
+### 5.1.1 Configuration File Section
+
+The authoritative `[telemetry]` example lives in `cfg/xrpld-example.cfg`. Telemetry is disabled by default (`enabled=0`); enabling it turns on distributed tracing for transaction flow, consensus, and RPC calls, with traces exported to an OpenTelemetry Collector over OTLP. Head sampling is intentionally fixed at 1.0 (sample everything) and is not configurable — per-node head-sampling would produce broken/partial distributed traces, so volume reduction is delegated to the collector's tail sampling (see Section 7.4.2). The full option reference follows.
+
+### 5.1.2 Configuration Options Summary
+
+| Option                | Type   | Default                           | Description                                          |
+| --------------------- | ------ | --------------------------------- | ---------------------------------------------------- |
+| `enabled`             | bool   | `false`                           | Enable/disable telemetry                             |
+| `endpoint`            | string | `http://localhost:4318/v1/traces` | OTLP/HTTP collector endpoint                         |
+| `use_tls`             | bool   | `false`                           | Enable TLS for exporter connection                   |
+| `tls_ca_cert`         | string | `""`                              | Path to CA certificate file                          |
+| `batch_size`          | uint   | `512`                             | Spans per export batch                               |
+| `batch_delay_ms`      | uint   | `5000`                            | Max delay before sending batch (ms)                  |
+| `max_queue_size`      | uint   | `2048`                            | Maximum queued spans                                 |
+| `trace_transactions`  | 0 or 1 | `1`                               | Enable transaction tracing                           |
+| `trace_consensus`     | 0 or 1 | `1`                               | Enable consensus tracing                             |
+| `trace_rpc`           | 0 or 1 | `1`                               | Enable RPC tracing                                   |
+| `trace_peer`          | 0 or 1 | `1`                               | Enable peer message tracing (high volume)            |
+| `trace_ledger`        | 0 or 1 | `1`                               | Enable ledger tracing                                |
+| `service_name`        | string | `"xrpld"`                         | Service name (`service.name`) for traces and metrics |
+| `service_instance_id` | string | `<node_pubkey>`                   | Instance identifier                                  |
+
+**Planned (not yet implemented)**: the following options appear in the design
+documents but are not parsed by `TelemetryConfig.cpp` in Phase 1b and later
+phases. They will be added as the corresponding subsystems are instrumented:
+
+| Option                     | Planned Phase | Purpose                                                                 |
+| -------------------------- | ------------- | ----------------------------------------------------------------------- |
+| `exporter`                 | Future        | Select between OTLP/HTTP and OTLP/gRPC                                  |
+| `trace_pathfind`           | Phase 2       | Path computation tracing toggle                                         |
+| `trace_txq`                | Phase 3       | Transaction queue tracing toggle                                        |
+| `trace_validator`          | Future        | Validator list / manifest update tracing                                |
+| `trace_amendment`          | Future        | Amendment voting tracing                                                |
+| `consensus_trace_strategy` | Phase 4       | Trace ID strategy for consensus rounds (`deterministic` \| `attribute`) |
+
+---
+
+## 5.2 Configuration Parser
+
+> **TxQ** = Transaction Queue
+
+The parser `setup_Telemetry()` in `src/libxrpl/telemetry/TelemetryConfig.cpp` reads the `[telemetry]` `Section` and populates a `Telemetry::Setup` struct, applying the defaults listed in Section 5.1.2 via `section.value_or(...)`. It derives `serviceInstanceId` from the node public key when not overridden, selects the exporter endpoint default by exporter type, and leaves the sampling ratio at its fixed 1.0 default (not read from config — see Section 7.4.2).
+
+---
+
+## 5.3 Application Integration
+
+### 5.3.1 ApplicationImp Changes
+
+> **Deferred identity**: The node public key (`nodeIdentity_`) is not
+> available during `ApplicationImp`'s member initializer list — it is
+> resolved later in `setup()`. The `Telemetry` object is therefore
+> constructed with an empty `serviceInstanceId` and patched via
+> `setServiceInstanceId()` once `setup()` has called `getNodeIdentity()`.
+
+`ApplicationImp` (in `src/xrpld/app/main/Application.cpp`) owns a `std::unique_ptr<telemetry::Telemetry> telemetry_`. It is built in the member initializer list via `make_Telemetry(setup_Telemetry(...))` with an empty `serviceInstanceId`, then patched in `setup()` by calling `setServiceInstanceId()` with the Base58 node public key (unless the user supplied a custom `service_instance_id`). `start()` and `run()` forward to `telemetry_->start()` / `telemetry_->stop()`, and `getTelemetry()` returns the owned instance.
+
+### 5.3.2 ServiceRegistry Interface Addition
+
+`include/xrpl/core/ServiceRegistry.h` gains a pure-virtual `telemetry::Telemetry& getTelemetry()` (with a forward declaration of `telemetry::Telemetry`), giving every component a uniform accessor for the tracing subsystem.
+
+> **Note:** `Application` extends `ServiceRegistry`, so `getTelemetry()` is
+> available on both. Components that hold a `ServiceRegistry&` (e.g.
+> `NetworkOPsImp`) call `registry_.get().getTelemetry()`. Components that
+> still hold an `Application&` (e.g. `ServerHandler`, `PeerImp`,
+> `RCLConsensusAdaptor`) call `app_.getTelemetry()` directly.
+
+---
+
+## 5.4 CMake Integration
+
+> **OTLP** = OpenTelemetry Protocol
+
+### 5.4.1 Find OpenTelemetry Module
+
+A `cmake/FindOpenTelemetry.cmake` module locates the OpenTelemetry C++ SDK. It first tries `find_package(opentelemetry-cpp CONFIG)`, aliasing the imported targets `OpenTelemetry::api`, `OpenTelemetry::sdk`, and `OpenTelemetry::otlp_grpc_exporter`, and falls back to `pkg-config` when no CMake config package is present.
+
+### 5.4.2 CMakeLists.txt Changes
+
+The top-level `CMakeLists.txt` adds an `XRPL_ENABLE_TELEMETRY` option (default `OFF`). When enabled, it runs `find_package(OpenTelemetry REQUIRED)`, defines the `XRPL_ENABLE_TELEMETRY` compile flag, and builds the `xrpl_telemetry` library from the real telemetry sources linked against the OpenTelemetry targets; when disabled, it builds the same target from a no-op `NullTelemetry.cpp` so call sites compile unchanged.
+
+---
+
+## 5.5 OpenTelemetry Collector Configuration
+
+> **OTLP** = OpenTelemetry Protocol | **APM** = Application Performance Monitoring
+
+The authoritative collector config lives in the repo at `docker/telemetry/otel-collector-config.yaml` (with Tempo backend config in `docker/telemetry/tempo.yaml`). The sections below summarize the development and production shapes of that pipeline.
+
+### 5.5.1 Development Configuration
+
+The development collector enables an OTLP receiver on both gRPC (`0.0.0.0:4317`) and HTTP (`0.0.0.0:4318`), a single `batch` processor (1s timeout, batch size 100), and two exporters: a `logging` exporter for console debugging and `otlp/tempo` (insecure) for trace visualization. The single `traces` pipeline wires receiver → batch → both exporters.
+
+### 5.5.2 Production Configuration
+
+The production collector adds TLS on the OTLP gRPC receiver and a richer processor chain: a `memory_limiter` (OOM guard), `batch` (5s timeout, size 512), `tail_sampling`, and an `attributes` processor that hashes sensitive fields (e.g. `tx_account`) and stamps `deployment.environment`. Tail sampling keeps all `ERROR` traces, slow consensus rounds (>5s) and slow RPC requests (>1s), and probabilistically samples the remainder at 10%. Exporters target Grafana Tempo (TLS) and Elastic APM; `health_check` and `zpages` extensions are enabled for operability.
+
+---
+
+## 5.6 Docker Compose Development Environment
+
+> **OTLP** = OpenTelemetry Protocol
+
+The authoritative development stack lives in the repo at `docker/telemetry/docker-compose.yml`. It brings up four services on a shared `xrpld-telemetry` network: an `otel-collector` (otel/opentelemetry-collector-contrib) exposing OTLP gRPC `4317`, OTLP HTTP `4318`, and health check `13133`; `tempo` for trace storage/visualization; `grafana` with provisioned datasources and dashboards (anonymous admin enabled); and an optional `prometheus` for metric correlation.
+
+---
+
+## 5.7 Configuration Architecture
+
+> **OTLP** = OpenTelemetry Protocol
+
+```mermaid
+flowchart TB
+    subgraph config["Configuration Sources"]
+        cfgFile["xrpld.cfg<br/>[telemetry] section"]
+        cmake["CMake<br/>XRPL_ENABLE_TELEMETRY"]
+    end
+
+    subgraph init["Initialization"]
+        parse["setup_Telemetry()"]
+        factory["make_Telemetry()"]
+    end
+
+    subgraph runtime["Runtime Components"]
+        tracer["TracerProvider"]
+        exporter["OTLP Exporter"]
+        processor["BatchProcessor"]
+    end
+
+    subgraph collector["Collector Pipeline"]
+        recv["Receivers"]
+        proc["Processors"]
+        exp["Exporters"]
+    end
+
+    cfgFile --> parse
+    cmake -->|"compile flag"| parse
+    parse --> factory
+    factory --> tracer
+    tracer --> processor
+    processor --> exporter
+    exporter -->|"OTLP"| recv
+    recv --> proc
+    proc --> exp
+
+    style config fill:#e3f2fd,stroke:#1976d2
+    style runtime fill:#e8f5e9,stroke:#388e3c
+    style collector fill:#fff3e0,stroke:#ff9800
+```
+
+**Reading the diagram:**
+
+- **Configuration Sources**: `xrpld.cfg` provides runtime settings (endpoint, per-component trace toggles) while the CMake flag controls whether telemetry is compiled in at all. Head sampling is fixed at 1.0 and is not a config option; volume reduction happens via tail sampling in the collector.
+- **Initialization**: `setup_Telemetry()` parses config values, then `make_Telemetry()` constructs the provider, processor, and exporter objects.
+- **Runtime Components**: The `TracerProvider` creates spans, the `BatchProcessor` buffers them, and the `OTLP Exporter` serializes and sends them over the wire.
+- **OTLP arrow to Collector**: Trace data leaves the xrpld process via OTLP/HTTP and enters the external Collector pipeline. (OTLP/gRPC is future work — see design decisions §2.2.2.)
+- **Collector Pipeline**: `Receivers` ingest OTLP data, `Processors` apply sampling/filtering/enrichment, and `Exporters` forward traces to storage backends (Tempo, etc.).
+
+---
+
+## 5.8 Grafana Integration
+
+> **APM** = Application Performance Monitoring
+
+Step-by-step instructions for integrating xrpld traces with Grafana.
+
+### 5.8.1 Data Source Configuration
+
+#### Tempo (Recommended)
+
+A Tempo datasource (`grafana/provisioning/datasources/tempo.yaml`, provisioned from `docker/telemetry/grafana/`) points at `http://tempo:3200` and enables `tracesToLogs` (linking to Loki on `service.name`/`tx_hash` and mapping `trace_id` → `traceID`), `serviceMap` against Prometheus, the node graph, and Loki search.
+
+#### Elastic APM
+
+Alternatively, an Elasticsearch datasource (`grafana/provisioning/datasources/elastic-apm.yaml`) of type `elasticsearch` points at `http://elasticsearch:9200` against the `apm-*` index, using `@timestamp` as the time field and mapping the log message/level fields.
+
+### 5.8.2 Dashboard Provisioning
+
+A dashboard provider (`grafana/provisioning/dashboards/dashboards.yaml`) loads the `xrpld` dashboard folder from disk (`/var/lib/grafana/dashboards/rippled`), polling for changes every 30s with deletion disabled.
+
+### 5.8.3 Example Dashboard: RPC Performance
+
+An example `xrpld RPC Performance` dashboard (uid `xrpld-rpc-performance`) sourced from Tempo via TraceQL provides four panels: RPC latency by command (heatmap), RPC error rate by command (timeseries), the top 10 slowest RPC commands by average duration (table), and a recent-traces table.
+
+### 5.8.4 Example Dashboard: Transaction Tracing
+
+An example `xrpld Transaction Tracing` dashboard (uid `xrpld-tx-tracing`) over Tempo provides three panels: transaction throughput (`tx.receive` rate, stat), cross-node relay count (average `span.relay_count` on `tx.relay`, timeseries), and a table of transaction validation errors (`tx.validate` with `status.code=error`).
+
+### 5.8.5 TraceQL Query Examples
+
+Common queries for xrpld traces:
+
+```
+# Find all traces for a specific transaction hash
+{resource.service.name="xrpld" && span.tx_hash="ABC123..."}
+
+# Find slow RPC commands (>100ms)
+{resource.service.name="xrpld" && name=~"rpc.command.*"} | duration > 100ms
+
+# Find consensus rounds taking >5 seconds
+{resource.service.name="xrpld" && name="consensus.round"} | duration > 5s
+
+# Find failed transactions with error details
+{resource.service.name="xrpld" && name="tx.validate" && status.code=error}
+
+# Find transactions relayed to many peers
+{resource.service.name="xrpld" && name="tx.relay"} | span.relay_count > 10
+
+# Compare latency across nodes
+{resource.service.name="xrpld" && name="rpc.command.account_info"} | avg(duration) by (resource.service.instance.id)
+```
+
+### 5.8.6 Correlation with PerfLog
+
+To correlate OpenTelemetry traces with existing PerfLog data:
+
+**Step 1: Configure Loki to ingest PerfLog**
+
+Configure a Promtail scrape job (`promtail-config.yaml`) that tails `/var/log/rippled/perf*.log`, parses each JSON line, and promotes `trace_id`, `ledger_seq`, and `tx_hash` to Loki labels.
+
+**Step 2: Add trace_id to PerfLog entries**
+
+Modify PerfLog so its JSON output includes a `trace_id` field whenever a valid span is active: fetch the current span from the OpenTelemetry runtime context, and if its context is valid, render the trace ID as a 32-character lowercase hex string into the log entry.
+
+**Step 3: Configure Grafana trace-to-logs link**
+
+In the Tempo datasource, set the `tracesToLogs` derived field to link to Loki on the `trace_id` and `tx_hash` tags, with `filterByTraceID: true`.
+
+### 5.8.7 Correlation with Insight/StatsD Metrics
+
+To correlate traces with existing Beast Insight metrics:
+
+**Step 1: Export Insight metrics to Prometheus**
+
+Add a Prometheus scrape job (`prometheus.yaml`) named `xrpld-statsd` targeting the StatsD exporter at `statsd-exporter:9102`.
+
+**Step 2: Add exemplars to metrics**
+
+The OpenTelemetry SDK automatically adds exemplars (trace IDs) to metrics when using the Prometheus exporter, linking metric spikes to specific traces.
+
+**Step 3: Configure Grafana metric-to-trace link**
+
+In the Prometheus datasource, set `exemplarTraceIdDestinations` to map the `trace_id` exemplar to the Tempo datasource.
+
+**Step 4: Dashboard panel with exemplars**
+
+Add a timeseries panel over Prometheus (e.g. `histogram_quantile(0.99, rate(xrpld_rpc_duration_seconds_bucket[5m]))`) with `exemplar: true` enabled.
+
+This allows clicking on metric data points to jump directly to the related trace.
+
+---
+
+_Previous: [Implementation Strategy](./03-implementation-strategy.md)_ | _Next: [Implementation Phases](./06-implementation-phases.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/06-implementation-phases.md

@@ -0,0 +1,575 @@
+# Implementation Phases
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Configuration Reference](./05-configuration-reference.md) | [Observability Backends](./07-observability-backends.md)
+
+---
+
+## 6.1 Phase Overview
+
+> **TxQ** = Transaction Queue
+
+```mermaid
+gantt
+    title OpenTelemetry Implementation Timeline
+    dateFormat  YYYY-MM-DD
+    axisFormat  Week %W
+
+    section Phase 1
+    Core Infrastructure        :p1, 2024-01-01, 2w
+    SDK Integration           :p1a, 2024-01-01, 4d
+    Telemetry Interface       :p1b, after p1a, 3d
+    Configuration & CMake     :p1c, after p1b, 3d
+    Unit Tests                :p1d, after p1c, 2d
+    Buffer & Integration      :p1e, after p1d, 2d
+
+    section Phase 2
+    RPC Tracing               :p2, after p1, 2w
+    HTTP Context Extraction   :p2a, after p1, 2d
+    RPC Handler Instrumentation :p2b, after p2a, 4d
+    PathFinding Instrumentation :p2f, after p2b, 2d
+    TxQ Instrumentation       :p2g, after p2f, 2d
+    WebSocket Support         :p2c, after p2g, 2d
+    Integration Tests         :p2d, after p2c, 2d
+    Buffer & Review           :p2e, after p2d, 4d
+
+    section Phase 3
+    Transaction Tracing       :p3, after p2, 2w
+    Protocol Buffer Extension :p3a, after p2, 2d
+    PeerImp Instrumentation   :p3b, after p3a, 3d
+    Fee Escalation Instrumentation :p3f, after p3b, 2d
+    Relay Context Propagation :p3c, after p3f, 3d
+    Multi-node Tests          :p3d, after p3c, 2d
+    Buffer & Review           :p3e, after p3d, 4d
+
+    section Phase 4
+    Consensus Tracing         :p4, after p3, 2w
+    Consensus Round Spans     :p4a, after p3, 3d
+    Proposal Handling         :p4b, after p4a, 3d
+    Validator List & Manifest Tracing :p4f, after p4b, 2d
+    Amendment Voting Tracing  :p4g, after p4f, 2d
+    SHAMap Sync Tracing       :p4h, after p4g, 2d
+    Validation Tests          :p4c, after p4h, 4d
+    Buffer & Review           :p4e, after p4c, 4d
+
+    section Phase 5
+    Documentation & Deploy    :p5, after p4, 1w
+```
+
+---
+
+## 6.2 Phase 1: Core Infrastructure (Weeks 1-2)
+
+**Objective**: Establish foundational telemetry infrastructure
+
+### Tasks
+
+| Task | Description                                           |
+| ---- | ----------------------------------------------------- |
+| 1.1  | Add OpenTelemetry C++ SDK to Conan/CMake              |
+| 1.2  | Implement `Telemetry` interface and factory           |
+| 1.3  | Implement `SpanGuard` RAII wrapper                    |
+| 1.4  | Implement configuration parser                        |
+| 1.5  | Integrate into `ApplicationImp`                       |
+| 1.6  | Add conditional compilation (`XRPL_ENABLE_TELEMETRY`) |
+| 1.7  | Create `NullTelemetry` no-op implementation           |
+| 1.8  | Unit tests for core infrastructure                    |
+
+### Exit Criteria
+
+- [ ] OpenTelemetry SDK compiles and links
+- [ ] Telemetry can be enabled/disabled via config
+- [ ] Basic span creation works
+- [ ] No performance regression when disabled
+- [ ] Unit tests passing
+
+---
+
+## 6.3 Phase 2: RPC Tracing (Weeks 3-4)
+
+> **TxQ** = Transaction Queue
+
+**Objective**: Complete tracing for all RPC operations
+
+### Tasks
+
+| Task | Description                                                                |
+| ---- | -------------------------------------------------------------------------- |
+| 2.1  | Implement W3C Trace Context HTTP header extraction                         |
+| 2.2  | Instrument `ServerHandler::onRequest()`                                    |
+| 2.3  | Instrument `RPCHandler::doCommand()`                                       |
+| 2.4  | Add RPC-specific attributes                                                |
+| 2.5  | Instrument WebSocket handler                                               |
+| 2.6  | PathFinding instrumentation (`pathfind.request`, `pathfind.compute` spans) |
+| 2.7  | TxQ instrumentation (`txq.enqueue`, `txq.apply` spans)                     |
+| 2.8  | Integration tests for RPC tracing                                          |
+| 2.9  | Performance benchmarks                                                     |
+| 2.10 | Documentation                                                              |
+
+### Exit Criteria
+
+- [ ] All RPC commands traced
+- [ ] Trace context propagates from HTTP headers
+- [ ] WebSocket and HTTP both instrumented
+- [ ] <1ms overhead per RPC call
+- [ ] Integration tests passing
+
+---
+
+## 6.4 Phase 3: Transaction Tracing (Weeks 5-6)
+
+**Objective**: Trace transaction lifecycle across network
+
+### Tasks
+
+| Task | Description                                          |
+| ---- | ---------------------------------------------------- |
+| 3.1  | Define `TraceContext` Protocol Buffer message        |
+| 3.2  | Implement protobuf context serialization             |
+| 3.3  | Instrument `PeerImp::handleTransaction()`            |
+| 3.4  | Instrument `NetworkOPs::submitTransaction()`         |
+| 3.5  | Instrument HashRouter integration                    |
+| 3.6  | Fee escalation instrumentation (`fee.escalate` span) |
+| 3.7  | Implement relay context propagation                  |
+| 3.8  | Integration tests (multi-node)                       |
+| 3.9  | Performance benchmarks                               |
+
+### Exit Criteria
+
+- [ ] Transaction traces span across nodes
+- [ ] Trace context in Protocol Buffer messages
+- [ ] HashRouter deduplication visible in traces
+- [ ] Multi-node integration tests passing
+- [ ] <5% overhead on transaction throughput
+
+---
+
+## 6.5 Phase 4: Consensus Tracing (Weeks 7-8)
+
+**Objective**: Full observability into consensus rounds
+
+### Tasks
+
+| Task | Description                                    |
+| ---- | ---------------------------------------------- |
+| 4.1  | Instrument `RCLConsensusAdaptor::startRound()` |
+| 4.2  | Instrument phase transitions                   |
+| 4.3  | Instrument proposal handling                   |
+| 4.4  | Instrument validation handling                 |
+| 4.5  | Add consensus-specific attributes              |
+| 4.6  | Correlate with transaction traces              |
+| 4.7  | Validator list and manifest tracing            |
+| 4.8  | Amendment voting tracing                       |
+| 4.9  | SHAMap sync tracing                            |
+| 4.10 | Multi-validator integration tests              |
+| 4.11 | Performance validation                         |
+
+### Exit Criteria
+
+- [ ] Complete consensus round traces
+- [ ] Phase transitions visible
+- [ ] Proposals and validations traced
+- [ ] No impact on consensus timing
+- [ ] Multi-validator test network validated
+
+### Implementation Status — Phase 4a Plan
+
+Phase 4a (establish-phase gap fill & cross-node correlation) will add:
+
+- **Deterministic trace ID** derived from `previousLedger.id()` so all validators
+  in the same round share the same `trace_id` (switchable via
+  `consensus_trace_strategy` config: `"deterministic"` or `"attribute"`).
+  See [Configuration Reference](./05-configuration-reference.md) for full
+  configuration options.
+- **Round lifecycle spans**: `consensus.round` with round-to-round span links.
+- **Establish phase**: `consensus.establish`, `consensus.update_positions` (with
+  `dispute.resolve` events), `consensus.check` (with threshold tracking).
+- **Mode changes**: `consensus.mode_change` spans.
+- **Validation**: `consensus.validation.send` with span link to round span
+  (thread-safe cross-thread access via `roundSpanContext_` snapshot).
+- **Separation of concerns**: telemetry extracted to private helpers
+  (`startRoundTracing`, `createValidationSpan`, `startEstablishTracing`,
+  `updateEstablishTracing`, `endEstablishTracing`).
+
+The `Phase4_taskList.md` spec document is introduced in the Phase 2 PR (#6424)
+and will contain the full task breakdown and implementation notes.
+
+---
+
+## 6.6 Phase 5: Documentation & Deployment (Week 9)
+
+**Objective**: Production readiness
+
+### Tasks
+
+| Task | Description                   |
+| ---- | ----------------------------- |
+| 5.1  | Operator runbook              |
+| 5.2  | Grafana dashboards            |
+| 5.3  | Alert definitions             |
+| 5.4  | Collector deployment examples |
+| 5.5  | Developer documentation       |
+| 5.6  | Training materials            |
+| 5.7  | Final integration testing     |
+
+---
+
+## 6.7 Risk Assessment
+
+```mermaid
+quadrantChart
+    title Risk Assessment Matrix
+    x-axis Low Impact --> High Impact
+    y-axis Low Likelihood --> High Likelihood
+    quadrant-1 Mitigate Immediately
+    quadrant-2 Plan Mitigation
+    quadrant-3 Accept Risk
+    quadrant-4 Monitor Closely
+
+    SDK Compat: [0.2, 0.18]
+    Protocol Chg: [0.75, 0.72]
+    Perf Overhead: [0.58, 0.42]
+    Context Prop: [0.4, 0.55]
+    Memory Leaks: [0.85, 0.25]
+```
+
+### Risk Details
+
+| Risk                                 | Likelihood | Impact | Mitigation                              |
+| ------------------------------------ | ---------- | ------ | --------------------------------------- |
+| Protocol changes break compatibility | Medium     | High   | Use high field numbers, optional fields |
+| Performance overhead unacceptable    | Medium     | Medium | Sampling, conditional compilation       |
+| Context propagation complexity       | Medium     | Medium | Phased rollout, extensive testing       |
+| SDK compatibility issues             | Low        | Medium | Pin SDK version, fallback to no-op      |
+| Memory leaks in long-running nodes   | Low        | High   | Memory profiling, bounded queues        |
+
+---
+
+## 6.8 Success Metrics
+
+| Metric                   | Target                                                         | Measurement           |
+| ------------------------ | -------------------------------------------------------------- | --------------------- |
+| Trace coverage           | >95% of transaction code paths (independent of sampling ratio) | Sampling verification |
+| CPU overhead             | <3%                                                            | Benchmark tests       |
+| Memory overhead          | <10 MB                                                         | Memory profiling      |
+| Latency impact (p99)     | <2%                                                            | Performance tests     |
+| Trace completeness       | >99% spans with required attrs                                 | Validation script     |
+| Cross-node trace linkage | >90% of multi-hop transactions                                 | Integration tests     |
+
+---
+
+## 6.9 Quick Wins and Crawl-Walk-Run Strategy
+
+> **TxQ** = Transaction Queue
+
+This section outlines a prioritized approach to maximize ROI with minimal initial investment.
+
+### 6.9.1 Crawl-Walk-Run Overview
+
+<div align="center">
+
+```mermaid
+flowchart TB
+    subgraph crawl["🐢 CRAWL (Week 1-2)"]
+        direction LR
+        c1[Core SDK Setup] ~~~ c2[RPC Tracing Only] ~~~ c3[PathFinding + TxQ Tracing] ~~~ c4[Single Node]
+    end
+
+    subgraph walk["🚶 WALK (Week 3-5)"]
+        direction LR
+        w1[Transaction Tracing] ~~~ w2[Fee Escalation Tracing] ~~~ w3[Cross-Node Context] ~~~ w4[Basic Dashboards]
+    end
+
+    subgraph run["🏃 RUN (Week 6-9)"]
+        direction LR
+        r1[Consensus Tracing] ~~~ r2[Validator, Amendment,<br/>SHAMap Tracing] ~~~ r3[Full Correlation] ~~~ r4[Production Deploy]
+    end
+
+    crawl --> walk --> run
+
+    style crawl fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style walk fill:#bf360c,stroke:#8c2809,color:#fff
+    style run fill:#0d47a1,stroke:#082f6a,color:#fff
+    style c1 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style c2 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style c3 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style c4 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style w1 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style w2 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style w3 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style w4 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style r1 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style r2 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style r3 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style r4 fill:#0d47a1,stroke:#082f6a,color:#fff
+```
+
+</div>
+
+**Reading the diagram:**
+
+- **CRAWL (Weeks 1-2)**: Minimal investment -- set up the SDK, instrument RPC and PathFinding/TxQ handlers, and verify on a single node. Delivers immediate latency visibility.
+- **WALK (Weeks 3-5)**: Expand to transaction lifecycle tracing, fee escalation, cross-node context propagation, and basic Grafana dashboards. This is where distributed tracing starts working.
+- **RUN (Weeks 6-9)**: Full consensus instrumentation, validator/amendment/SHAMap tracing, end-to-end correlation, and production deployment with sampling and alerting.
+- **Arrows (crawl → walk → run)**: Each phase builds on the prior one; you cannot skip ahead because later phases depend on infrastructure established earlier.
+
+### 6.9.2 Quick Wins (Immediate Value)
+
+| Quick Win                      | Value  | When to Deploy |
+| ------------------------------ | ------ | -------------- |
+| **RPC Command Tracing**        | High   | Week 2         |
+| **RPC Latency Histograms**     | High   | Week 2         |
+| **Error Rate Dashboard**       | Medium | Week 2         |
+| **Transaction Submit Tracing** | High   | Week 3         |
+| **Consensus Round Duration**   | Medium | Week 6         |
+
+### 6.9.3 CRAWL Phase (Weeks 1-2)
+
+**Goal**: Get basic tracing working with minimal code changes.
+
+**What You Get**:
+
+- RPC request/response traces for all commands
+- Latency breakdown per RPC command
+- PathFinding and TxQ tracing (directly impacts RPC latency)
+- Error visibility with stack traces
+- Basic Grafana dashboard
+
+**Code Changes**: ~15 lines in `ServerHandler.cpp`, ~40 lines in new telemetry module
+
+**Why Start Here**:
+
+- RPC is the lowest-risk, highest-visibility component
+- PathFinding and TxQ are RPC-adjacent and directly affect latency
+- Immediate value for debugging client issues
+- No cross-node complexity
+- Single file modification to existing code
+
+### 6.9.4 WALK Phase (Weeks 3-5)
+
+**Goal**: Add transaction lifecycle tracing across nodes.
+
+**What You Get**:
+
+- End-to-end transaction traces from submit to relay
+- Fee escalation tracing within the transaction pipeline
+- Cross-node correlation (see transaction path)
+- HashRouter deduplication visibility
+- Relay latency metrics
+
+**Code Changes**: ~120 lines across 4 files, plus protobuf extension
+
+**Why Do This Second**:
+
+- Builds on RPC tracing (transactions submitted via RPC)
+- Fee escalation is integral to the transaction processing pipeline
+- Moderate complexity (requires context propagation)
+- High value for debugging transaction issues
+
+### 6.9.5 RUN Phase (Weeks 6-9)
+
+**Goal**: Full observability including consensus.
+
+**What You Get**:
+
+- Complete consensus round visibility
+- Phase transition timing
+- Validator proposal tracking
+- Validator list and manifest tracing
+- Amendment voting tracing
+- SHAMap sync tracing
+- Full end-to-end traces (client → RPC → TX → consensus → ledger)
+
+**Code Changes**: ~100 lines across 3 consensus files, plus validator/amendment/SHAMap modules
+
+**Why Do This Last**:
+
+- Highest complexity (consensus is critical path)
+- Validator, amendment, and SHAMap components are lower priority
+- Requires thorough testing
+- Lower relative value (consensus issues are rarer)
+
+### 6.9.6 ROI Prioritization Matrix
+
+```mermaid
+quadrantChart
+    title Implementation ROI Matrix
+    x-axis Low Effort --> High Effort
+    y-axis Low Value --> High Value
+    quadrant-1 Quick Wins - Do First
+    quadrant-2 Major Projects - Plan Carefully
+    quadrant-3 Nice to Have - Optional
+    quadrant-4 Time Sinks - Avoid
+
+    RPC Tracing: [0.15, 0.92]
+    TX Submit Trace: [0.3, 0.78]
+    TX Relay Trace: [0.5, 0.88]
+    Consensus Trace: [0.72, 0.72]
+    Peer Msg Trace: [0.85, 0.3]
+    Ledger Acquire: [0.55, 0.52]
+```
+
+---
+
+## 6.10 Definition of Done
+
+> **TxQ** = Transaction Queue | **HA** = High Availability
+
+Clear, measurable criteria for each phase.
+
+### 6.10.1 Phase 1: Core Infrastructure
+
+| Criterion       | Measurement                                                | Target                       |
+| --------------- | ---------------------------------------------------------- | ---------------------------- |
+| SDK Integration | `cmake --build` succeeds with `-DXRPL_ENABLE_TELEMETRY=ON` | ✅ Compiles                  |
+| Runtime Toggle  | `enabled=0` produces zero overhead                         | <0.1% CPU difference         |
+| Span Creation   | Unit test creates and exports span                         | Span appears in Tempo        |
+| Configuration   | All config options parsed correctly                        | Config validation tests pass |
+| Documentation   | Developer guide exists                                     | PR approved                  |
+
+**Definition of Done**: All criteria met, PR merged, no regressions in CI.
+
+### 6.10.2 Phase 2: RPC Tracing
+
+| Criterion          | Measurement                        | Target                     |
+| ------------------ | ---------------------------------- | -------------------------- |
+| Coverage           | All RPC commands instrumented      | 100% of commands           |
+| Context Extraction | traceparent header propagates      | Integration test passes    |
+| Attributes         | Command, status, duration recorded | Validation script confirms |
+| Performance        | RPC latency overhead               | <1ms p99                   |
+| Dashboard          | Grafana dashboard deployed         | Screenshot in docs         |
+
+**Definition of Done**: RPC traces visible in Tempo for all commands, dashboard shows latency distribution.
+
+### 6.10.3 Phase 3: Transaction Tracing
+
+| Criterion        | Measurement                     | Target                             |
+| ---------------- | ------------------------------- | ---------------------------------- |
+| Local Trace      | Submit → validate → TxQ traced  | Single-node test passes            |
+| Cross-Node       | Context propagates via protobuf | Multi-node test passes             |
+| Relay Visibility | relay_count attribute correct   | Spot check 100 txs                 |
+| HashRouter       | Deduplication visible in trace  | Duplicate txs show suppressed=true |
+| Performance      | TX throughput overhead          | <5% degradation                    |
+
+**Definition of Done**: Transaction traces span 3+ nodes in test network, performance within bounds.
+
+### 6.10.4 Phase 4: Consensus Tracing
+
+| Criterion            | Measurement                   | Target                    |
+| -------------------- | ----------------------------- | ------------------------- |
+| Round Tracing        | startRound creates root span  | Unit test passes          |
+| Phase Visibility     | All phases have child spans   | Integration test confirms |
+| Proposer Attribution | Proposer ID in attributes     | Spot check 50 rounds      |
+| Timing Accuracy      | Phase durations match PerfLog | <5% variance              |
+| No Consensus Impact  | Round timing unchanged        | Performance test passes   |
+
+**Definition of Done**: Consensus rounds fully traceable, no impact on consensus timing.
+
+### 6.10.5 Phase 5: Production Deployment
+
+| Criterion    | Measurement                  | Target                     |
+| ------------ | ---------------------------- | -------------------------- |
+| Collector HA | Multiple collectors deployed | No single point of failure |
+| Sampling     | Tail sampling configured     | 10% base + errors + slow   |
+| Retention    | Data retained per policy     | 7 days hot, 30 days warm   |
+| Alerting     | Alerts configured            | Error spike, high latency  |
+| Runbook      | Operator documentation       | Approved by ops team       |
+| Training     | Team trained                 | Session completed          |
+
+**Definition of Done**: Telemetry running in production, operators trained, alerts active.
+
+### 6.10.6 Success Metrics Summary
+
+| Phase   | Primary Metric         | Secondary Metric            | Deadline      |
+| ------- | ---------------------- | --------------------------- | ------------- |
+| Phase 1 | SDK compiles and runs  | Zero overhead when disabled | End of Week 2 |
+| Phase 2 | 100% RPC coverage      | <1ms latency overhead       | End of Week 4 |
+| Phase 3 | Cross-node traces work | <5% throughput impact       | End of Week 6 |
+| Phase 4 | Consensus fully traced | No consensus timing impact  | End of Week 8 |
+| Phase 5 | Production deployment  | Operators trained           | End of Week 9 |
+
+---
+
+## 6.11 Recommended Implementation Order
+
+Based on ROI analysis, implement in this exact order:
+
+```mermaid
+flowchart TB
+    subgraph week1["Week 1"]
+        t1[1. OpenTelemetry SDK<br/>Conan/CMake integration]
+        t2[2. Telemetry interface<br/>SpanGuard, config]
+    end
+
+    subgraph week2["Week 2"]
+        t3[3. RPC ServerHandler<br/>instrumentation]
+        t4[4. Basic Tempo setup<br/>for testing]
+    end
+
+    subgraph week3["Week 3"]
+        t5[5. Transaction submit<br/>tracing]
+        t6[6. Grafana dashboard<br/>v1]
+    end
+
+    subgraph week4["Week 4"]
+        t7[7. Protobuf context<br/>extension]
+        t8[8. PeerImp tx.relay<br/>instrumentation]
+    end
+
+    subgraph week5["Week 5"]
+        t9[9. Multi-node<br/>integration tests]
+        t10[10. Performance<br/>benchmarks]
+    end
+
+    subgraph week6_8["Weeks 6-8"]
+        t11[11. Consensus<br/>instrumentation]
+        t12[12. Full integration<br/>testing]
+    end
+
+    subgraph week9["Week 9"]
+        t13[13. Production<br/>deployment]
+        t14[14. Documentation<br/>& training]
+    end
+
+    t1 --> t2 --> t3 --> t4
+    t4 --> t5 --> t6
+    t6 --> t7 --> t8
+    t8 --> t9 --> t10
+    t10 --> t11 --> t12
+    t12 --> t13 --> t14
+
+    style week1 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style week2 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style week3 fill:#bf360c,stroke:#8c2809,color:#fff
+    style week4 fill:#bf360c,stroke:#8c2809,color:#fff
+    style week5 fill:#bf360c,stroke:#8c2809,color:#fff
+    style week6_8 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style week9 fill:#4a148c,stroke:#2e0d57,color:#fff
+    style t1 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style t2 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style t3 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style t4 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style t5 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t6 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t7 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t8 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t9 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t10 fill:#ffe0b2,stroke:#ffcc80,color:#1e293b
+    style t11 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style t12 fill:#0d47a1,stroke:#082f6a,color:#fff
+    style t13 fill:#4a148c,stroke:#2e0d57,color:#fff
+    style t14 fill:#4a148c,stroke:#2e0d57,color:#fff
+```
+
+**Reading the diagram:**
+
+- **Week 1 (tasks 1-2)**: Foundation work -- integrate the OpenTelemetry SDK via Conan/CMake and build the `Telemetry` interface with `SpanGuard` and config parsing.
+- **Week 2 (tasks 3-4)**: First observable output -- instrument `ServerHandler` for RPC tracing and stand up Tempo so developers can see traces immediately.
+- **Weeks 3-5 (tasks 5-10)**: Transaction lifecycle -- add submit tracing, build the first Grafana dashboard, extend protobuf for cross-node context, instrument `PeerImp` relay, then validate with multi-node integration tests and performance benchmarks.
+- **Weeks 6-8 (tasks 11-12)**: Consensus deep-dive -- instrument consensus rounds and phases, then run full integration testing across all instrumented paths.
+- **Week 9 (tasks 13-14)**: Go-live -- deploy to production with sampling/alerting configured, and deliver documentation and operator training.
+- **Arrow chain (t1 → ... → t14)**: Strict sequential dependency; each task's output is a prerequisite for the next.
+
+---
+
+_Previous: [Configuration Reference](./05-configuration-reference.md)_ | _Next: [Observability Backends](./07-observability-backends.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/07-observability-backends.md

@@ -0,0 +1,407 @@
+# Observability Backend Recommendations
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Implementation Phases](./06-implementation-phases.md) | [Appendix](./08-appendix.md)
+
+---
+
+## 7.1 Development/Testing Backends
+
+> **OTLP** = OpenTelemetry Protocol
+
+| Backend    | Pros                                | Cons                   | Use Case            |
+| ---------- | ----------------------------------- | ---------------------- | ------------------- |
+| **Tempo**  | Cost-effective, Grafana integration | Requires Grafana stack | Local dev, CI, Prod |
+| **Zipkin** | Simple, lightweight                 | Basic features         | Quick prototyping   |
+
+### Quick Start with Tempo
+
+```bash
+# Start Tempo with OTLP support
+docker run -d --name tempo \
+    -p 3200:3200 \
+    -p 4317:4317 \
+    -p 4318:4318 \
+    grafana/tempo:2.6.1
+```
+
+---
+
+## 7.2 Production Backends
+
+> **APM** = Application Performance Monitoring
+
+| Backend           | Pros                                      | Cons                   | Use Case                    |
+| ----------------- | ----------------------------------------- | ---------------------- | --------------------------- |
+| **Grafana Tempo** | Cost-effective, Grafana integration       | Requires Grafana stack | Most production deployments |
+| **Elastic APM**   | Full observability stack, log correlation | Resource intensive     | Existing Elastic users      |
+| **Honeycomb**     | Excellent query, high cardinality         | SaaS cost              | Deep debugging needs        |
+| **Datadog APM**   | Full platform, easy setup                 | SaaS cost              | Enterprise with budget      |
+
+### Backend Selection Flowchart
+
+```mermaid
+flowchart TD
+    start[Select Backend] --> budget{Budget<br/>Constraints?}
+
+    budget -->|Yes| oss[Open Source]
+    budget -->|No| saas{Prefer<br/>SaaS?}
+
+    oss --> existing{Existing<br/>Stack?}
+    existing -->|Grafana| tempo[Grafana Tempo]
+    existing -->|Elastic| elastic[Elastic APM]
+    existing -->|None| tempo
+
+    saas -->|Yes| enterprise{Enterprise<br/>Support?}
+    saas -->|No| oss
+
+    enterprise -->|Yes| datadog[Datadog APM]
+    enterprise -->|No| honeycomb[Honeycomb]
+
+    tempo --> final[Configure Collector]
+    elastic --> final
+    honeycomb --> final
+    datadog --> final
+
+    style start fill:#0f172a,stroke:#020617,color:#fff
+    style budget fill:#334155,stroke:#1e293b,color:#fff
+    style oss fill:#1e293b,stroke:#0f172a,color:#fff
+    style existing fill:#334155,stroke:#1e293b,color:#fff
+    style saas fill:#334155,stroke:#1e293b,color:#fff
+    style enterprise fill:#334155,stroke:#1e293b,color:#fff
+    style final fill:#0f172a,stroke:#020617,color:#fff
+    style tempo fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style elastic fill:#bf360c,stroke:#8c2809,color:#fff
+    style honeycomb fill:#0d47a1,stroke:#082f6a,color:#fff
+    style datadog fill:#4a148c,stroke:#2e0d57,color:#fff
+```
+
+**Reading the diagram:**
+
+- **Budget Constraints? (Yes)**: Leads to open-source options. If you already run Grafana or Elastic, pick the matching backend; otherwise default to Grafana Tempo.
+- **Budget Constraints? (No) → Prefer SaaS?**: If you want a managed service, choose between Datadog (enterprise support) and Honeycomb (developer-focused). If not, fall back to open-source.
+- **Terminal nodes (Tempo / Elastic / Honeycomb / Datadog)**: Each represents a concrete backend choice, all of which feed into the same final step.
+- **Configure Collector**: Regardless of backend, you always finish by configuring the OTel Collector to export to your chosen destination.
+
+---
+
+## 7.3 Recommended Production Architecture
+
+> **OTLP** = OpenTelemetry Protocol | **APM** = Application Performance Monitoring | **HA** = High Availability
+
+```mermaid
+flowchart TB
+    subgraph validators["Validator Nodes"]
+        v1[xrpld<br/>Validator 1]
+        v2[xrpld<br/>Validator 2]
+    end
+
+    subgraph stock["Stock Nodes"]
+        s1[xrpld<br/>Stock 1]
+        s2[xrpld<br/>Stock 2]
+    end
+
+    subgraph collector["OTel Collector Cluster"]
+        c1[Collector<br/>DC1]
+        c2[Collector<br/>DC2]
+    end
+
+    subgraph backends["Storage Backends"]
+        tempo[(Grafana<br/>Tempo)]
+        elastic[(Elastic<br/>APM)]
+        archive[(S3/GCS<br/>Archive)]
+    end
+
+    subgraph ui["Visualization"]
+        grafana[Grafana<br/>Dashboards]
+    end
+
+    v1 -->|OTLP| c1
+    v2 -->|OTLP| c1
+    s1 -->|OTLP| c2
+    s2 -->|OTLP| c2
+
+    c1 --> tempo
+    c1 --> elastic
+    c2 --> tempo
+    c2 --> archive
+
+    tempo --> grafana
+    elastic --> grafana
+
+    %% Note: simplified single-collector-per-DC topology shown for clarity
+
+    style validators fill:#b71c1c,stroke:#7f1d1d,color:#ffffff
+    style stock fill:#0d47a1,stroke:#082f6a,color:#ffffff
+    style collector fill:#bf360c,stroke:#8c2809,color:#ffffff
+    style backends fill:#1b5e20,stroke:#0d3d14,color:#ffffff
+    style ui fill:#4a148c,stroke:#2e0d57,color:#ffffff
+```
+
+**Reading the diagram:**
+
+- **Validator / Stock Nodes**: All xrpld nodes emit trace data via OTLP. Validators and stock nodes are grouped separately because they may reside in different network zones.
+- **Collector Cluster (DC1, DC2)**: Regional collectors receive OTLP from nodes in their datacenter, apply processing (sampling, enrichment), and fan out to multiple backends. Enrichment includes deployment-tier tagging: each collector stamps `deployment.environment` and (as a fallback) `xrpl.network.type` so one Grafana stack can filter data from many collectors by tier.
+- **Storage Backends**: Tempo and Elastic provide queryable trace storage; S3/GCS Archive provides long-term cold storage for compliance or post-incident analysis.
+- **Grafana Dashboards**: The single visualization layer that queries both Tempo and Elastic, giving operators a unified view of all traces.
+- **Data flow direction**: Nodes → Collectors → Storage → Grafana. Each arrow represents a network hop; minimizing collector-to-backend hops reduces latency.
+
+> **Note**: Production deployments should use multiple collector instances behind a load balancer for high availability. The diagram shows a simplified single-collector topology for clarity.
+
+---
+
+## 7.4 Architecture Considerations
+
+### 7.4.1 Collector Placement
+
+| Strategy      | Description          | Pros                     | Cons                    |
+| ------------- | -------------------- | ------------------------ | ----------------------- |
+| **Sidecar**   | Collector per node   | Isolation, simple config | Resource overhead       |
+| **DaemonSet** | Collector per host   | Shared resources         | Complexity              |
+| **Gateway**   | Central collector(s) | Centralized processing   | Single point of failure |
+
+**Recommendation**: Use **Gateway** pattern with regional collectors for xrpld networks:
+
+- One collector cluster per datacenter/region
+- Tail-based sampling at collector level
+- Multiple export destinations for redundancy
+
+### 7.4.2 Sampling Strategy
+
+```mermaid
+flowchart LR
+    subgraph head["Head Sampling (Node)"]
+        hs[Node-level head sampling<br/>fixed at 100%<br/>not configurable]
+    end
+
+    subgraph tail["Tail Sampling (Collector)"]
+        ts1[Keep all errors]
+        ts2[Keep slow >5s]
+        ts3[Keep 10% rest]
+    end
+
+    head --> tail
+
+    ts1 --> final[Final Traces]
+    ts2 --> final
+    ts3 --> final
+
+    style head fill:#0d47a1,stroke:#082f6a,color:#fff
+    style tail fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style hs fill:#0d47a1,stroke:#082f6a,color:#fff
+    style ts1 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style ts2 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style ts3 fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style final fill:#bf360c,stroke:#8c2809,color:#fff
+```
+
+**Reading the diagram:**
+
+- **Head Sampling (Node)**: xrpld pins head sampling at 100% (sample everything) and does not expose a configurable ratio. This is intentional: a per-node ratio would let different nodes make divergent keep/drop decisions for the same distributed trace, producing broken/partial traces. xrpld uses a `ParentBased` sampler so spans inheriting a remote parent honor the upstream decision. Volume reduction is delegated to the collector's tail sampling.
+- **Tail Sampling (Collector)**: The second filter -- the collector inspects completed traces and applies rules: keep all errors, keep anything slower than 5 seconds, and keep 10% of the remainder.
+- **Arrow head → tail**: All head-sampled traces flow to the collector, where tail sampling further reduces volume while preserving the most valuable data.
+- **Final Traces**: The output after both sampling stages; this is what gets stored and queried. The two-stage approach balances cost with debuggability.
+
+### 7.4.3 Data Retention
+
+| Environment | Hot Storage | Warm Storage | Cold Archive |
+| ----------- | ----------- | ------------ | ------------ |
+| Development | 24 hours    | N/A          | N/A          |
+| Staging     | 7 days      | N/A          | N/A          |
+| Production  | 7 days      | 30 days      | many years   |
+
+---
+
+## 7.5 Integration Checklist
+
+- [ ] Choose primary backend (Tempo recommended for cost/features)
+- [ ] Deploy collector cluster with high availability
+- [ ] Configure tail-based sampling for error/latency traces
+- [ ] Set up Grafana dashboards for trace visualization
+- [ ] Configure alerts for trace anomalies
+- [ ] Establish data retention policies
+- [ ] Test trace correlation with logs and metrics
+
+---
+
+## 7.6 Grafana Dashboard Examples
+
+Pre-built dashboards for xrpld observability.
+
+### 7.6.1 Consensus Health Dashboard
+
+A Tempo-backed dashboard (uid `xrpld-consensus-health`) with four panels, all driven by TraceQL:
+
+- **Consensus Round Duration** (timeseries, ms): average `consensus.round` span duration per node instance, with yellow/red thresholds at 4s/5s.
+- **Phase Duration Breakdown** (barchart): average duration of `consensus.phase.*` spans grouped by span name.
+- **Proposers per Round** (stat): average of the `span.proposers` attribute on `consensus.round` spans.
+- **Recent Slow Rounds (>5s)** (table): `consensus.round` spans filtered to `duration > 5s`.
+
+Each panel's TraceQL query is described inline in its bullet above.
+
+### 7.6.2 Node Overview Dashboard
+
+A Tempo-backed dashboard (uid `xrpld-node-overview`) with four panels:
+
+- **Active Nodes** (stat): count of distinct `resource.service.instance.id` values seen for the `xrpld` service.
+- **Total Transactions (1h)** (stat): count of `tx.receive` spans.
+- **Error Rate** (gauge, percent): ratio of `status.code=error` spans to all spans, with yellow/red thresholds at 1%/5%.
+- **Service Map** (nodeGraph): Tempo-generated service dependency graph.
+
+### 7.6.3 Alert Rules
+
+Grafana provisions three TraceQL-based alert rules (group `xrpld-tracing-alerts`, evaluated every 1m) against the Tempo datasource:
+
+- **Consensus Round Slow** (warning, `for: 5m`): fires when average `consensus.round` duration exceeds 5s.
+
+  ```
+  {resource.service.name="xrpld" && name="consensus.round"} | avg(duration) > 5s
+  ```
+
+- **RPC Error Rate Spike** (critical, `for: 2m`): fires when the error rate across `rpc.command.*` spans exceeds 5%. Error _rate_ is a ratio, so it must divide the error-span rate by the total-span rate — a single TraceQL `rate()` returns spans/second, not a percentage, and would fire on traffic volume alone. This uses span metrics emitted by the collector's `spanmetrics` connector (Prometheus datasource), not a TraceQL query:
+
+  ```
+  sum(rate(traces_spanmetrics_calls_total{service_name="xrpld", span_name=~"rpc.command.*", status_code="STATUS_CODE_ERROR"}[5m]))
+  /
+  sum(rate(traces_spanmetrics_calls_total{service_name="xrpld", span_name=~"rpc.command.*"}[5m]))
+  > 0.05
+  ```
+
+- **Transaction Throughput Drop** (warning, `for: 10m`): fires when the `tx.receive` span rate falls below 10/s.
+
+  ```
+  {resource.service.name="xrpld" && name="tx.receive"} | rate() < 10
+  ```
+
+> **Note**: The Consensus Round Slow and Transaction Throughput Drop rules use TraceQL aggregates (`avg(duration)`, `rate()`), which require Tempo 2.3+ with TraceQL metrics enabled. Verify aggregate query support in your Tempo version before provisioning. The RPC Error Rate Spike rule instead queries Prometheus span metrics (collector `spanmetrics` connector), so it needs that connector enabled in the collector pipeline.
+
+---
+
+## 7.7 PerfLog and Insight Correlation
+
+> **OTLP** = OpenTelemetry Protocol
+
+How to correlate OpenTelemetry traces with existing xrpld observability.
+
+### 7.7.1 Correlation Architecture
+
+```mermaid
+flowchart TB
+    subgraph xrpld["xrpld Node"]
+        otel[OpenTelemetry<br/>Spans]
+        perflog[PerfLog<br/>JSON Logs]
+        insight[Beast Insight<br/>StatsD Metrics]
+    end
+
+    subgraph collectors["Data Collection"]
+        otelc[OTel Collector]
+        promtail[Promtail/Fluentd]
+        statsd[StatsD Exporter]
+    end
+
+    subgraph storage["Storage"]
+        tempo[(Tempo)]
+        loki[(Loki)]
+        prom[(Prometheus)]
+    end
+
+    subgraph grafana["Grafana"]
+        traces[Trace View]
+        logs[Log View]
+        metrics[Metrics View]
+        corr[Correlation<br/>Panel]
+    end
+
+    otel -->|OTLP| otelc --> tempo
+    perflog -->|JSON| promtail --> loki
+    insight -->|StatsD| statsd --> prom
+
+    tempo --> traces
+    loki --> logs
+    prom --> metrics
+
+    traces --> corr
+    logs --> corr
+    metrics --> corr
+
+    style xrpld fill:#0d47a1,stroke:#082f6a,color:#fff
+    style collectors fill:#bf360c,stroke:#8c2809,color:#fff
+    style storage fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style grafana fill:#4a148c,stroke:#2e0d57,color:#fff
+    style otel fill:#0d47a1,stroke:#082f6a,color:#fff
+    style perflog fill:#0d47a1,stroke:#082f6a,color:#fff
+    style insight fill:#0d47a1,stroke:#082f6a,color:#fff
+    style otelc fill:#bf360c,stroke:#8c2809,color:#fff
+    style promtail fill:#bf360c,stroke:#8c2809,color:#fff
+    style statsd fill:#bf360c,stroke:#8c2809,color:#fff
+    style tempo fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style loki fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style prom fill:#1b5e20,stroke:#0d3d14,color:#fff
+    style traces fill:#4a148c,stroke:#2e0d57,color:#fff
+    style logs fill:#4a148c,stroke:#2e0d57,color:#fff
+    style metrics fill:#4a148c,stroke:#2e0d57,color:#fff
+    style corr fill:#4a148c,stroke:#2e0d57,color:#fff
+```
+
+**Reading the diagram:**
+
+- **xrpld Node (three sources)**: A single node emits three independent data streams -- OpenTelemetry spans, PerfLog JSON logs, and Beast Insight StatsD metrics.
+- **Data Collection layer**: Each stream has its own collector -- OTel Collector for spans, Promtail/Fluentd for logs, and a StatsD exporter for metrics. They operate independently.
+- **Storage layer (Tempo, Loki, Prometheus)**: Each data type lands in a purpose-built store optimized for its query patterns (trace search, log grep, metric aggregation).
+- **Grafana Correlation Panel**: The key integration point -- Grafana queries all three stores and links them via shared fields (`trace_id`, `tx_hash`, `ledger_seq`), enabling a single-pane debugging experience.
+
+### 7.7.2 Correlation Fields
+
+| Source      | Field               | Link To       | Purpose                    |
+| ----------- | ------------------- | ------------- | -------------------------- |
+| **Trace**   | `trace_id`          | Logs          | Find log entries for trace |
+| **Trace**   | `tx_hash`           | Logs, Metrics | Find TX-related data       |
+| **Trace**   | `ledger_seq`        | Logs          | Find ledger-related logs   |
+| **PerfLog** | `trace_id` (new)    | Traces        | Jump to trace from log     |
+| **PerfLog** | `ledger_seq`        | Traces        | Find consensus trace       |
+| **Insight** | `exemplar.trace_id` | Traces        | Jump from metric spike     |
+
+### 7.7.3 Example: Debugging a Slow Transaction
+
+**Step 1: Find the trace**
+
+```
+# In Grafana Explore with Tempo
+{resource.service.name="xrpld" && span.tx_hash="ABC123..."}
+```
+
+**Step 2: Get the trace_id from the trace view**
+
+```
+Trace ID: 4bf92f3577b34da6a3ce929d0e0e4736
+```
+
+**Step 3: Find related PerfLog entries**
+
+```
+# In Grafana Explore with Loki
+{job="xrpld"} |= "4bf92f3577b34da6a3ce929d0e0e4736"
+```
+
+**Step 4: Check Insight metrics for the time window**
+
+```
+# In Grafana with Prometheus
+rate(xrpld_tx_applied_total[1m])
+  @ timestamp_from_trace
+```
+
+### 7.7.4 Unified Dashboard Example
+
+A single dashboard (uid `xrpld-unified`) that ties traces, metrics, and logs together across the Tempo, Prometheus, and Loki datasources:
+
+- **Transaction Latency (Traces)** (timeseries, Tempo): `histogram_over_time(duration)` of `tx.receive` spans.
+- **Transaction Rate (Metrics)** (timeseries, Prometheus): `rate(xrpld_tx_received_total[5m])` per instance, with a data link that opens the matching `tx.receive` traces in Tempo.
+- **Recent Logs** (logs, Loki): `{job="xrpld"} | json`.
+- **Trace Search** (table, Tempo): all `xrpld` traces, with per-row data links on `traceID` that jump to the trace in Tempo and to the correlated logs in Loki (`{job="xrpld"} |= "<traceID>"`).
+
+The cross-datasource data links are what make this a single-pane debugging view; the correlation fields they rely on are listed in section 7.7.2.
+
+---
+
+_Previous: [Implementation Phases](./06-implementation-phases.md)_ | _Next: [Appendix](./08-appendix.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/08-appendix.md

@@ -0,0 +1,187 @@
+# Appendix
+
+> **Parent Document**: [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)
+> **Related**: [Observability Backends](./07-observability-backends.md)
+
+---
+
+## 8.1 Glossary
+
+> **OTLP** = OpenTelemetry Protocol | **TxQ** = Transaction Queue
+
+| Term                  | Definition                                                 |
+| --------------------- | ---------------------------------------------------------- |
+| **Span**              | A unit of work with start/end time, name, and attributes   |
+| **Trace**             | A collection of spans representing a complete request flow |
+| **Trace ID**          | 128-bit unique identifier for a trace                      |
+| **Span ID**           | 64-bit unique identifier for a span within a trace         |
+| **Context**           | Carrier for trace/span IDs across boundaries               |
+| **Propagator**        | Component that injects/extracts context                    |
+| **Sampler**           | Decides which traces to record                             |
+| **Exporter**          | Sends spans to backend                                     |
+| **Collector**         | Receives, processes, and forwards telemetry                |
+| **OTLP**              | OpenTelemetry Protocol (wire format)                       |
+| **W3C Trace Context** | Standard HTTP headers for trace propagation                |
+| **Baggage**           | Key-value pairs propagated across service boundaries       |
+| **Resource**          | Entity producing telemetry (service, host, etc.)           |
+| **Instrumentation**   | Code that creates telemetry data                           |
+
+### xrpld-Specific Terms
+
+| Term              | Definition                                                    |
+| ----------------- | ------------------------------------------------------------- |
+| **Overlay**       | P2P network layer managing peer connections                   |
+| **Consensus**     | XRP Ledger consensus algorithm (RCL)                          |
+| **Proposal**      | Validator's suggested transaction set for a ledger            |
+| **Validation**    | Validator's signature on a closed ledger                      |
+| **HashRouter**    | Component for transaction deduplication                       |
+| **JobQueue**      | Thread pool for asynchronous task execution                   |
+| **PerfLog**       | Existing performance logging system in xrpld                  |
+| **Beast Insight** | Existing metrics framework in xrpld                           |
+| **PathFinding**   | Payment path computation engine for cross-currency payments   |
+| **TxQ**           | Transaction queue managing fee-based prioritization           |
+| **LoadManager**   | Dynamic fee escalation based on network load                  |
+| **SHAMap**        | SHA-256 hash-based map (Merkle trie variant) for ledger state |
+
+---
+
+## 8.2 Span Hierarchy Visualization
+
+> **TxQ** = Transaction Queue
+
+```mermaid
+flowchart TB
+    subgraph trace["Trace: Transaction Lifecycle"]
+        rpc["rpc.request<br/>(entry point)"]
+        validate["tx.validate"]
+        relay["tx.relay<br/>(parent span)"]
+
+        subgraph peers["Peer Spans"]
+            p1["peer.send<br/>Peer A"]
+            p2["peer.send<br/>Peer B"]
+            p3["peer.send<br/>Peer C"]
+        end
+
+        subgraph pathfinding["PathFinding Spans"]
+            pathfind["pathfind.request"]
+            pathcomp["pathfind.compute"]
+        end
+
+        consensus["consensus.round"]
+        apply["tx.apply"]
+
+        subgraph txqueue["TxQ Spans"]
+            txq["txq.enqueue"]
+            txqApply["txq.apply"]
+        end
+
+        feeCalc["fee.escalate"]
+    end
+
+    subgraph validators["Validator Spans"]
+        valFetch["validator.list.fetch"]
+        valManifest["validator.manifest"]
+    end
+
+    rpc --> validate
+    rpc --> pathfind
+    pathfind --> pathcomp
+    validate --> relay
+    relay --> p1
+    relay --> p2
+    relay --> p3
+    p1 -.->|"context propagation"| consensus
+    consensus --> apply
+    apply --> txq
+    txq --> txqApply
+    txq --> feeCalc
+
+    style trace fill:#0f172a,stroke:#020617,color:#fff
+    style peers fill:#1e3a8a,stroke:#172554,color:#fff
+    style pathfinding fill:#134e4a,stroke:#0f766e,color:#fff
+    style txqueue fill:#064e3b,stroke:#047857,color:#fff
+    style validators fill:#4c1d95,stroke:#6d28d9,color:#fff
+    style rpc fill:#1d4ed8,stroke:#1e40af,color:#fff
+    style validate fill:#047857,stroke:#064e3b,color:#fff
+    style relay fill:#047857,stroke:#064e3b,color:#fff
+    style p1 fill:#0e7490,stroke:#155e75,color:#fff
+    style p2 fill:#0e7490,stroke:#155e75,color:#fff
+    style p3 fill:#0e7490,stroke:#155e75,color:#fff
+    style consensus fill:#fef3c7,stroke:#fde68a,color:#1e293b
+    style apply fill:#047857,stroke:#064e3b,color:#fff
+    style pathfind fill:#0e7490,stroke:#155e75,color:#fff
+    style pathcomp fill:#0e7490,stroke:#155e75,color:#fff
+    style txq fill:#047857,stroke:#064e3b,color:#fff
+    style txqApply fill:#047857,stroke:#064e3b,color:#fff
+    style feeCalc fill:#047857,stroke:#064e3b,color:#fff
+    style valFetch fill:#6d28d9,stroke:#4c1d95,color:#fff
+    style valManifest fill:#6d28d9,stroke:#4c1d95,color:#fff
+```
+
+**Reading the diagram:**
+
+- **rpc.request (blue, top)**: The entry point — every traced transaction starts as an RPC call; this root span is the parent of all downstream work.
+- **tx.validate and pathfind.request (green/teal, first fork)**: The RPC request fans out into transaction validation and, for cross-currency payments, a PathFinding branch (`pathfind.request` -> `pathfind.compute`).
+- **tx.relay -> Peer Spans (teal, middle)**: After validation, the transaction is relayed to peers A, B, and C in parallel; each `peer.send` is a sibling child span showing fan-out across the network.
+- **context propagation (dashed arrow)**: The dotted line from `peer.send Peer A` to `consensus.round` represents the trace context crossing a node boundary — the receiving validator picks up the same `trace_id` and continues the trace.
+- **consensus.round -> tx.apply -> TxQ Spans (green, lower)**: Once consensus accepts the transaction, it is applied to the ledger; the TxQ spans (`txq.enqueue`, `txq.apply`, `fee.escalate`) capture queue depth and fee escalation behavior.
+- **Validator Spans (purple, detached)**: `validator.list.fetch` and `validator.manifest` are independent workflows for UNL management — they run on their own traces and are linked to consensus via Span Links, not parent-child relationships.
+
+---
+
+## 8.3 References
+
+> **OTLP** = OpenTelemetry Protocol
+
+### OpenTelemetry Resources
+
+1. [OpenTelemetry C++ SDK](https://github.com/open-telemetry/opentelemetry-cpp)
+2. [OpenTelemetry Specification](https://opentelemetry.io/docs/specs/otel/)
+3. [OpenTelemetry Collector](https://opentelemetry.io/docs/collector/)
+4. [OTLP Protocol Specification](https://opentelemetry.io/docs/specs/otlp/)
+
+### Standards
+
+5. [W3C Trace Context](https://www.w3.org/TR/trace-context/)
+6. [W3C Baggage](https://www.w3.org/TR/baggage/)
+7. [Protocol Buffers](https://protobuf.dev/)
+
+### xrpld Resources
+
+8. [xrpld Source Code](https://github.com/XRPLF/rippled)
+9. [XRP Ledger Documentation](https://xrpl.org/docs/)
+10. [xrpld Overlay README](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/overlay/README.md)
+11. [xrpld RPC README](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/rpc/README.md)
+12. [xrpld Consensus README](https://github.com/XRPLF/rippled/blob/develop/src/xrpld/app/consensus/README.md)
+
+---
+
+## 8.4 Version History
+
+| Version | Date       | Author | Changes                                                        |
+| ------- | ---------- | ------ | -------------------------------------------------------------- |
+| 1.0     | 2026-02-12 | -      | Initial implementation plan                                    |
+| 1.1     | 2026-02-13 | -      | Refactored into modular documents                              |
+| 1.2     | 2026-03-24 | -      | Review fixes: accuracy corrections, cross-document consistency |
+
+---
+
+## 8.5 Document Index
+
+### Plan Documents
+
+| Document                                                         | Description                                  |
+| ---------------------------------------------------------------- | -------------------------------------------- |
+| [OpenTelemetryPlan.md](./OpenTelemetryPlan.md)                   | Master overview and executive summary        |
+| [00-tracing-fundamentals.md](./00-tracing-fundamentals.md)       | Distributed tracing concepts and OTel primer |
+| [01-architecture-analysis.md](./01-architecture-analysis.md)     | xrpld architecture and trace points          |
+| [02-design-decisions.md](./02-design-decisions.md)               | SDK selection, exporters, span conventions   |
+| [03-implementation-strategy.md](./03-implementation-strategy.md) | Directory structure, performance analysis    |
+| [05-configuration-reference.md](./05-configuration-reference.md) | xrpld config, CMake, Collector configs       |
+| [06-implementation-phases.md](./06-implementation-phases.md)     | Timeline, tasks, risks, success metrics      |
+| [07-observability-backends.md](./07-observability-backends.md)   | Backend selection and architecture           |
+| [08-appendix.md](./08-appendix.md)                               | Glossary, references, version history        |
+
+---
+
+_Previous: [Observability Backends](./07-observability-backends.md)_ | _Back to: [Overview](./OpenTelemetryPlan.md)_

OpenTelemetryPlan/OpenTelemetryPlan.md

@@ -0,0 +1,199 @@
+# [OpenTelemetry](00-tracing-fundamentals.md) Distributed Tracing Implementation Plan for xrpld
+
+## Executive Summary
+
+> **OTLP** = OpenTelemetry Protocol
+
+This document provides a comprehensive implementation plan for integrating OpenTelemetry distributed tracing into the xrpld XRP Ledger node software. The plan addresses the unique challenges of a decentralized peer-to-peer system where trace context must propagate across network boundaries between independent nodes.
+
+### Key Benefits
+
+- **End-to-end transaction visibility**: Track transactions from submission through consensus to ledger inclusion
+- **Consensus round analysis**: Understand timing and behavior of consensus phases across validators
+- **RPC performance insights**: Identify slow handlers and optimize response times
+- **Network topology understanding**: Visualize message propagation patterns between peers
+- **Incident debugging**: Correlate events across distributed nodes during issues
+
+### Estimated Performance Overhead
+
+| Metric        | Overhead   | Notes                                            |
+| ------------- | ---------- | ------------------------------------------------ |
+| CPU           | 1-3%       | Span creation and attribute setting              |
+| Memory        | <10 MB     | SDK statics + batch buffer + worker thread stack |
+| Network       | 10-50 KB/s | Compressed OTLP export to collector              |
+| Latency (p99) | <2%        | With proper sampling configuration               |
+
+---
+
+## Document Structure
+
+This implementation plan is organized into modular documents for easier navigation:
+
+<div align="center">
+
+```mermaid
+flowchart TB
+    overview["📋 OpenTelemetryPlan.md<br/>(This Document)"]
+
+    subgraph fundamentals["Fundamentals"]
+        fund["00-tracing-fundamentals.md"]
+    end
+
+    subgraph analysis["Analysis & Design"]
+        arch["01-architecture-analysis.md"]
+        design["02-design-decisions.md"]
+    end
+
+    subgraph impl["Implementation"]
+        strategy["03-implementation-strategy.md"]
+        config["05-configuration-reference.md"]
+    end
+
+    subgraph deploy["Deployment & Planning"]
+        phases["06-implementation-phases.md"]
+        backends["07-observability-backends.md"]
+        appendix["08-appendix.md"]
+    end
+
+    overview --> fundamentals
+    overview --> analysis
+    overview --> impl
+    overview --> deploy
+
+    fund --> arch
+    arch --> design
+    design --> strategy
+    strategy --> config
+    config --> phases
+    phases --> backends
+    backends --> appendix
+
+    style overview fill:#1b5e20,stroke:#0d3d14,color:#fff,stroke-width:2px
+    style fundamentals fill:#00695c,stroke:#004d40,color:#fff
+    style fund fill:#00695c,stroke:#004d40,color:#fff
+    style analysis fill:#0d47a1,stroke:#082f6a,color:#fff
+    style impl fill:#bf360c,stroke:#8c2809,color:#fff
+    style deploy fill:#4a148c,stroke:#2e0d57,color:#fff
+    style arch fill:#0d47a1,stroke:#082f6a,color:#fff
+    style design fill:#0d47a1,stroke:#082f6a,color:#fff
+    style strategy fill:#bf360c,stroke:#8c2809,color:#fff
+    style config fill:#bf360c,stroke:#8c2809,color:#fff
+    style phases fill:#4a148c,stroke:#2e0d57,color:#fff
+    style backends fill:#4a148c,stroke:#2e0d57,color:#fff
+    style appendix fill:#4a148c,stroke:#2e0d57,color:#fff
+```
+
+</div>
+
+---
+
+## Table of Contents
+
+| Section | Document                                                   | Description                                                            |
+| ------- | ---------------------------------------------------------- | ---------------------------------------------------------------------- |
+| **0**   | [Tracing Fundamentals](./00-tracing-fundamentals.md)       | Distributed tracing concepts, span relationships, context propagation  |
+| **1**   | [Architecture Analysis](./01-architecture-analysis.md)     | xrpld component analysis, trace points, instrumentation priorities     |
+| **2**   | [Design Decisions](./02-design-decisions.md)               | SDK selection, exporters, span naming, attributes, context propagation |
+| **3**   | [Implementation Strategy](./03-implementation-strategy.md) | Directory structure, key principles, performance optimization          |
+| **5**   | [Configuration Reference](./05-configuration-reference.md) | xrpld config, CMake integration, Collector configurations              |
+| **6**   | [Implementation Phases](./06-implementation-phases.md)     | 5-phase timeline, tasks, risks, success metrics                        |
+| **7**   | [Observability Backends](./07-observability-backends.md)   | Backend selection guide and production architecture                    |
+| **8**   | [Appendix](./08-appendix.md)                               | Glossary, references, version history                                  |
+
+---
+
+## 0. Tracing Fundamentals
+
+This document introduces distributed tracing concepts for readers unfamiliar with the domain. It covers what traces and spans are, how parent-child and follows-from relationships model causality, how context propagates across service boundaries, and how sampling controls data volume. It also maps these concepts to xrpld-specific scenarios like transaction relay and consensus.
+
+➡️ **[Read Tracing Fundamentals](./00-tracing-fundamentals.md)**
+
+---
+
+## 1. Architecture Analysis
+
+> **WS** = WebSocket | **TxQ** = Transaction Queue
+
+The xrpld node consists of several key components that require instrumentation for comprehensive distributed tracing. The main areas include the RPC server (HTTP/WebSocket), Overlay P2P network, Consensus mechanism (RCLConsensus), JobQueue for async task execution, PathFinding, Transaction Queue (TxQ), fee escalation (LoadManager), ledger acquisition, validator management, and existing observability infrastructure (PerfLog, Insight/StatsD, Journal logging).
+
+Key trace points span across transaction submission via RPC, peer-to-peer message propagation, consensus round execution, ledger building, path computation, transaction queue behavior, fee escalation, and validator health. The implementation prioritizes high-value, low-risk components first: RPC handlers provide immediate value with minimal risk, while consensus tracing requires careful implementation to avoid timing impacts.
+
+➡️ **[Read full Architecture Analysis](./01-architecture-analysis.md)**
+
+---
+
+## 2. Design Decisions
+
+> **OTLP** = OpenTelemetry Protocol | **CNCF** = Cloud Native Computing Foundation
+
+The OpenTelemetry C++ SDK is selected for its CNCF backing, active development, and native performance characteristics. Traces are exported via OTLP/HTTP to an OpenTelemetry Collector, which provides flexible routing and sampling. OTLP/gRPC is planned future work (see design decisions §2.2.2).
+
+Span naming follows a hierarchical `<component>.<operation>` convention (e.g., `rpc.submit`, `tx.relay`, `consensus.round`). Context propagation uses W3C Trace Context headers for HTTP and embedded Protocol Buffer fields for P2P messages. The implementation coexists with existing PerfLog and Insight observability systems through correlation IDs.
+
+**Data Collection & Privacy**: Telemetry collects only operational metadata (timing, counts, hashes) — never sensitive content (private keys, balances, amounts, raw payloads). Privacy protection includes account hashing, configurable redaction, sampling, and collector-level filtering. Node operators retain full control over telemetry configuration.
+
+➡️ **[Read full Design Decisions](./02-design-decisions.md)**
+
+---
+
+## 3. Implementation Strategy
+
+The telemetry code is organized under `include/xrpl/telemetry/` for headers and `src/libxrpl/telemetry/` for implementation. Key principles include RAII-based span management via `SpanGuard`, conditional compilation with `XRPL_ENABLE_TELEMETRY`, and minimal runtime overhead through batch processing and efficient sampling.
+
+Performance optimization strategies include head sampling fixed at 100% (intentionally not configurable, so trace keep/drop decisions stay coherent across nodes), tail-based sampling at the collector for errors and slow traces to reduce volume, batch export to reduce network overhead, and conditional instrumentation that compiles to no-ops when disabled.
+
+➡️ **[Read full Implementation Strategy](./03-implementation-strategy.md)**
+
+---
+
+## 5. Configuration Reference
+
+> **OTLP** = OpenTelemetry Protocol | **APM** = Application Performance Monitoring
+
+Configuration is handled through the `[telemetry]` section in `xrpld.cfg` with options for enabling/disabling, exporter selection, endpoint configuration, and component-level filtering. Head sampling is fixed at 1.0 (not operator-configurable); volume reduction is done by tail sampling in the collector. CMake integration includes a `XRPL_ENABLE_TELEMETRY` option for compile-time control.
+
+OpenTelemetry Collector configurations are provided for development and production (with tail-based sampling, Tempo, and Elastic APM). Docker Compose examples enable quick local development environment setup.
+
+➡️ **[View full Configuration Reference](./05-configuration-reference.md)**
+
+---
+
+## 6. Implementation Phases
+
+The implementation spans 9 weeks across 5 phases:
+
+| Phase | Duration  | Focus               | Key Deliverables                                    |
+| ----- | --------- | ------------------- | --------------------------------------------------- |
+| 1     | Weeks 1-2 | Core Infrastructure | SDK integration, Telemetry interface, Configuration |
+| 2     | Weeks 3-4 | RPC Tracing         | HTTP context extraction, Handler instrumentation    |
+| 3     | Weeks 5-6 | Transaction Tracing | Protocol Buffer context, Relay propagation          |
+| 4     | Weeks 7-8 | Consensus Tracing   | Round spans, Proposal/validation tracing            |
+| 5     | Week 9    | Documentation       | Runbook, Dashboards, Training                       |
+
+**Total Effort**: 47 person-days (2 developers working in parallel)
+
+➡️ **[View full Implementation Phases](./06-implementation-phases.md)**
+
+---
+
+## 7. Observability Backends
+
+> **APM** = Application Performance Monitoring | **GCS** = Google Cloud Storage
+
+Grafana Tempo is recommended for all environments due to its cost-effectiveness and Grafana integration, while Elastic APM is ideal for organizations with existing Elastic infrastructure.
+
+The recommended production architecture uses a gateway collector pattern with regional collectors performing tail-based sampling, routing traces to multiple backends (Tempo for primary storage, Elastic for log correlation, S3/GCS for long-term archive).
+
+➡️ **[View Observability Backend Recommendations](./07-observability-backends.md)**
+
+---
+
+## 8. Appendix
+
+The appendix contains a glossary of OpenTelemetry and xrpld-specific terms, references to external documentation and specifications, version history for this implementation plan, and a complete document index.
+
+➡️ **[View Appendix](./08-appendix.md)**
+
+---
+
+_This document provides a comprehensive implementation plan for integrating OpenTelemetry distributed tracing into the xrpld XRP Ledger node software. For detailed information on any section, follow the links to the corresponding sub-documents._

README.md

@@ -54,6 +54,7 @@ Here are some good places to start learning the source code:
 | `./docs`   | Source documentation files and doxygen config. |
 | `./cfg`    | Example configuration files.                   |
 | `./src`    | Source code.                                   |
+| `./crates` | Rust source code.                              |
 
 Some of the directories under `src` are external repositories included using
 git-subtree. See those directories' README files for more details.

bin/check-nix-store-refs.sh

@@ -0,0 +1,111 @@
+#!/usr/bin/env bash
+# Fail if a binary under <path> records a /nix/store path it resolves at run
+# time. See docs/build/nix.md#prebuilt-packages for why that matters.
+#
+# <path> is a file or a directory. macOS: nothing may reference the store, so
+# point it at whole trees. Linux: the toolchain always writes the store into
+# PT_INTERP and RUNPATH, so only at what cmake/PatchNixBinary.cmake retargets.
+#
+# Only Mach-O / ELF is inspected. Static archives hold store paths in debug info
+# alone; the scripts in a Conan cache are all git hook samples and autotools
+# scratch, 36 false positives to 0 real.
+#
+# Usage: bin/check-nix-store-refs.sh <path>
+
+set -euo pipefail
+
+if [ "$#" -ne 1 ]; then
+    echo "usage: $0 <path>" >&2
+    exit 2
+fi
+
+if [ ! -e "$1" ]; then
+    echo "$0: no such path: $1" >&2
+    exit 2
+fi
+
+case "$(uname -s)" in
+    Darwin)
+        format=Mach-O
+        recorded_paths=macho_recorded_paths
+        tool=otool
+        ;;
+    Linux)
+        format=ELF
+        recorded_paths=elf_recorded_paths
+        tool=readelf
+        ;;
+    *)
+        echo "Unsupported OS - skipping the Nix store reference check."
+        exit 0
+        ;;
+esac
+
+# `pipefail` would catch this too, but only as a bare nonzero exit.
+if ! command -v "${tool}" >/dev/null; then
+    echo "$0: ${tool} not found; cannot inspect binaries" >&2
+    exit 2
+fi
+
+# Both list what the file records. `ldd` would answer what this machine resolves
+# now, which is wrong both ways: store paths for a correctly patched binary,
+# silence for a store RUNPATH that resolves nowhere.
+
+# `name` covers LC_ID_DYLIB and LC_LOAD*_DYLIB, `path` covers LC_RPATH.
+macho_recorded_paths() {
+    otool -l "$1" | sed -nE 's#^ *(name|path) ([^ ]*).*#\2#p'
+}
+
+# RPATH and RUNPATH are colon-separated.
+elf_recorded_paths() {
+    readelf -ldW "$1" |
+        sed -nE \
+            -e 's#.*program interpreter: ([^]]*)\].*#\1#p' \
+            -e 's#.*\((RPATH|RUNPATH|NEEDED)\).*\[([^]]*)\].*#\2#p' |
+        tr ':' '\n'
+}
+
+checked=0
+skipped=0
+leaked=0
+
+while IFS= read -r file; do
+    case "$(file -b "${file}" 2>/dev/null)" in
+        *"${format}"*) ;;
+        *)
+            skipped=$((skipped + 1))
+            continue
+            ;;
+    esac
+    checked=$((checked + 1))
+
+    # Filter after extracting, or a search path starting elsewhere ($ORIGIN)
+    # hides the rest. `sed` not `grep`: grep calls "no matches" a failure, and
+    # the `|| true` that would need masks a broken pipeline too.
+    refs="$("${recorded_paths}" "${file}" | sed -n '\#^/nix/store/#p' | sort -u)"
+    if [ -n "${refs}" ]; then
+        leaked=$((leaked + 1))
+        echo "::error file=${file}::references the Nix store at run time"
+        echo "${file}"
+        echo "${refs}" | sed 's/^/    /'
+    fi
+done < <(find "$1" -type f \( -perm -u+x -o -name '*.dylib' -o -name '*.so*' \))
+
+echo "$1: checked ${checked}, skipped ${skipped}, ${leaked} with Nix store references."
+
+if [ "${leaked}" -ne 0 ]; then
+    cat >&2 <<'EOF'
+
+Fixes, in order of preference:
+  - A Conan package built before this check existed: drop it
+    (`conan remove '<name>/*'`) and rebuild.
+  - A binary that should have been retargeted to the system loader: check that
+    cmake/PatchNixBinary.cmake ran for it.
+  - Link the macOS system library instead of the Nix one - see
+    libresolvSystemStub in nix/darwin.nix.
+  - No system library exists (libstdc++): link it statically.
+  - None of the above: pin the toolchain into the package ID, following
+    `user.package:libc_version` in conan/profiles/ci.
+EOF
+    exit 1
+fi

bin/check-tools.sh

@@ -0,0 +1,217 @@
+#!/usr/bin/env bash
+#
+# check-tools.sh — verify the xrpld development tooling is present and runnable.
+#
+# Works on Linux, macOS, and Windows (Git Bash / MSYS). For every expected tool
+# it runs a version probe, collecting anything that is missing or fails to run,
+# and prints a summary at the end (exiting non-zero if anything is missing).
+#
+# The tool set is platform-aware:
+#   - Linux:   the full Nix CI environment (see nix/packages.nix, nix/ci-env.nix),
+#              with GCC, Clang and the sanitizer/coverage tooling. This script is
+#              run during the Nix Docker image build (nix/docker/Dockerfile), so
+#              the Linux list is kept in sync with that environment.
+#   - macOS:   the same tooling, minus GCC/g++/gcov/mold
+#   - Windows: the core build tools only (CMake, Conan, Git, Python).
+#              MSVC is expected to be provided separately and is not checked here.
+#
+# Some tools (clang-format, clang-tidy, doxygen, gcovr, gh, git-cliff, gpg,
+# pre-commit, run-clang-tidy) are present in our Linux CI images and in local
+# development setups, but not in the macOS CI environment. They are checked
+# everywhere except when running in CI on macOS.
+#
+# Tools that Nix also exposes under a version-suffixed name (`clang-tidy-22`,
+# `g++-15`, ...) are probed under both names: a suffixed name can break while
+# the plain one still works (see mkVersionedToolLinks in nix/packages.nix).
+#
+# Environment variables:
+#   CI                      if set, skip the tools above when on macOS.
+#   CHECK_TOOLS_SKIP_CLONE  if set, skip the git-over-HTTPS connectivity check.
+
+set -uo pipefail
+
+# Version suffixes of the Nix tool links, tracking nix/packages.nix.
+gcc_version=15
+llvm_version=22
+
+missing=()
+checked=0
+
+# tool_path <name>
+# Fully resolved path of a tool, so the snapshots record which derivation
+# provides it. Prints nothing when it isn't on PATH.
+tool_path() {
+    local path
+    path="$(command -v "$1" 2>/dev/null)" || return 0
+    readlink -f "${path}" 2>/dev/null || printf '%s' "${path}"
+}
+
+# check <name> [probe-command...]
+# Runs the probe (default: "<name> --version"), capturing both stdout and
+# stderr, and prints three lines: the status and name, the first non-blank line
+# of the probe output (its version, or the error when it failed), and the tool's
+# resolved path. Records <name> as missing if it is not found or exits non-zero.
+check() {
+    local name="$1"
+    shift
+    local -a probe=("$@")
+    if [ "${#probe[@]}" -eq 0 ]; then
+        probe=("${name}" --version)
+    fi
+
+    checked=$((checked + 1))
+    local output version path
+    path="$(tool_path "${name}")"
+    if output="$("${probe[@]}" 2>&1)"; then
+        printf '  ✅ %s\n' "${name}"
+    else
+        printf '  ❌ %s\n' "${name}"
+        missing+=("${name}")
+    fi
+    version="$(printf '%s\n' "${output}" | grep -m1 '[^[:space:]]' || true)"
+    printf '     %s\n' "${version:-(no output)}"
+    printf '     %s\n' "${path:-(not found)}"
+}
+
+case "$(uname -s)" in
+    Linux*) os=linux ;;
+    Darwin*) os=macos ;;
+    MINGW* | MSYS* | CYGWIN*) os=windows ;;
+    *)
+        echo "Unknown OS: $(uname -s)" >&2
+        exit 1
+        ;;
+esac
+
+echo "Detected OS: ${os} ($(uname -s) $(uname -m))"
+echo
+echo "Core build tools:"
+check cmake
+check conan
+check git
+if [ "${os}" = "windows" ]; then
+    check python python --version
+else
+    check python3
+fi
+
+# The full development toolchain. Available from Nix on Linux and macOS; on
+# Windows these are typically not installed, so they are skipped.
+if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
+    echo
+    echo "Development tooling:"
+    check ccache
+    check clang
+    check "clang-${llvm_version}"
+    check clang++
+    check "clang++-${llvm_version}"
+    check ClangBuildAnalyzer
+    check curl
+    check file
+    check less
+    check make
+    # net-tools netstat reports "net-tools X.Y"; macOS ships BSD netstat with no
+    # version flag, so fall back to a presence marker there.
+    check netstat sh -c 'command -v netstat >/dev/null && { netstat --version 2>&1 | grep -m1 -oE "net-tools [0-9.]+" || echo present; }'
+    check ninja
+    check perl perl -e 'print "$^V\n"'
+    check pkg-config
+    check vim
+    check zip bash -c 'zip --version 2>&1 | grep -m1 -oE "Zip [0-9.]+"'
+
+    # These tools are present in our Linux CI images and in local development
+    # setups, but not in the macOS CI environment. So check them everywhere
+    # except when running in CI on macOS.
+    if [ "${os}" = "linux" ] || [ -z "${CI:-}" ]; then
+        check clang-apply-replacements
+        check "clang-apply-replacements-${llvm_version}"
+        check clang-format
+        check "clang-format-${llvm_version}"
+        # clang-tidy leads --version with the LLVM banner, not the version.
+        tidy_probe="--version | grep -m1 -oE 'LLVM version [0-9.]+'"
+        check clang-tidy sh -c "clang-tidy ${tidy_probe}"
+        check "clang-tidy-${llvm_version}" sh -c "clang-tidy-${llvm_version} ${tidy_probe}"
+        check dot
+        check doxygen
+        check gcovr
+        check gh
+        check git-cliff
+        check git-lfs
+        check gpg
+        # pre-commit, or its alternative implementation prek
+        check pre-commit sh -c 'pre-commit --version || prek --version'
+        check run-clang-tidy run-clang-tidy --help
+        check "run-clang-tidy-${llvm_version}" "run-clang-tidy-${llvm_version}" --help
+    fi
+fi
+
+# Rust toolchain. Part of the Nix commonPackages, so available on both Linux
+# and macOS. The cargo plugins are invoked through cargo (`cargo <sub>`), which
+# resolves the matching `cargo-<sub>` binary on PATH; `--version` is offline and
+# does not need a Cargo project.
+if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
+    echo
+    echo "Rust toolchain:"
+    check cargo
+    check cargo-audit cargo audit --version
+    check cargo-llvm-cov cargo llvm-cov --version
+    check cargo-nextest cargo nextest --version
+    check clippy-driver
+    check rust-analyzer
+    check rustc
+    check rustfmt
+fi
+
+# GCC is the default compiler on Linux. macOS uses the system Apple Clang
+# instead, so GCC/g++/gcov are not expected there.
+if [ "${os}" = "linux" ]; then
+    echo
+    echo "GCC toolchain:"
+    check gcc
+    check "gcc-${gcc_version}"
+    check g++
+    check "g++-${gcc_version}"
+    check cpp
+    check "cpp-${gcc_version}"
+    check gcov
+
+    echo
+    echo "Mold:"
+    check mold
+fi
+
+if [ "${os}" = "windows" ]; then
+    echo
+    echo "Note: on Windows the C++ compiler is MSVC, which is provided"
+    echo "      separately (e.g. via Visual Studio) and is not checked here."
+fi
+
+# A simple test to verify that git can clone a repository over HTTPS
+# (i.e. the CA bundle is wired up). Clone to a temp dir and clean up.
+if [ -n "${CHECK_TOOLS_SKIP_CLONE:-}" ]; then
+    echo
+    echo "Skipping git-over-HTTPS check (CHECK_TOOLS_SKIP_CLONE is set)."
+else
+    echo
+    echo "Connectivity check:"
+    checked=$((checked + 1))
+    tmp_clone="$(mktemp -d)"
+    if git clone --depth 1 https://github.com/XRPLF/actions.git "${tmp_clone}/actions" >/dev/null 2>&1; then
+        printf '  ✅ git clone over HTTPS\n'
+    else
+        printf '  ❌ git clone over HTTPS\n'
+        missing+=("git-https-clone")
+    fi
+    rm -rf "${tmp_clone}"
+fi
+
+echo
+if [ "${#missing[@]}" -eq 0 ]; then
+    echo "✅ All ${checked} checked tools are present and runnable."
+else
+    echo "❌ Missing or non-functional tools (${#missing[@]} of ${checked}):" >&2
+    for tool in "${missing[@]}"; do
+        echo "  - ${tool}" >&2
+    done
+    exit 1
+fi

bin/default-loader-path.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+case "$(uname -m)" in
+    x86_64) LOADER=/lib64/ld-linux-x86-64.so.2 ;;
+    aarch64) LOADER=/lib/ld-linux-aarch64.so.1 ;;
+    *)
+        echo "Unsupported arch: $(uname -m)" >&2
+        exit 1
+        ;;
+esac
+
+echo "${LOADER}"

bin/filter-clang-tidy.py

@@ -0,0 +1,102 @@
+#!/usr/bin/env python3
+
+"""
+Reduce run-clang-tidy output to its unique errors.
+
+It does two things:
+
+  1. Filters the raw output down to diagnostics and their source-context lines
+     (the indented "  103 | ..." / "      | ^" lines clang-tidy prints),
+     matching the "path:line:col: error:" diagnostic shape.
+
+  2. Deduplicates. The same diagnostic in a header is reported once per
+     translation unit that includes it, so identical error blocks are collapsed
+     to their first occurrence.
+
+An "error block" is an "error:" line together with the indented context lines
+and any "note:" lines that follow it (up to the next "error:" line). Blocks are
+compared as a whole, so an error stays attached to its own context, and
+first-occurrence order is preserved.
+
+The deduplicated output goes to stdout; a summary of unique error counts per
+check is printed to stderr.
+
+Usage:
+  bin/filter-clang-tidy.py [INPUT_FILE]            # read from file, or
+  run-clang-tidy ... | bin/filter-clang-tidy.py    # read from stdin
+"""
+
+import re
+import sys
+from collections import Counter
+
+# A clang-tidy diagnostic line looks like "path:line:col: error: msg [check]".
+# Matching on that shape (rather than a loose "error" substring) avoids treating
+# progress lines whose paths contain "error" as diagnostics, e.g.
+#   [284/850][0.7s] /nix/.../clang-tidy ... src/.../error.cpp
+DIAG_RE = re.compile(r":\d+:\d+: (?:error|warning|note):")
+ERROR_RE = re.compile(r":\d+:\d+: error:")
+CHECK_RE = re.compile(r" error: .*\[([^\],]+)")
+
+
+def filter_and_dedup(lines: list[str]) -> list[str]:
+    """Keep diagnostics with their context, then drop duplicate error blocks."""
+    blocks: list[str] = []
+    seen: set[str] = set()
+    current: list[str] = []
+
+    def flush() -> None:
+        if not current:
+            return
+        block = "".join(current)
+        if block not in seen:
+            seen.add(block)
+            blocks.append(block)
+
+    for line in lines:
+        # Keep only diagnostics and their indented source-context lines; drop
+        # progress/status output and blank lines.
+        if not (DIAG_RE.search(line) or line[:1] in (" ", "\t")):
+            continue
+        # An "error:" line starts a new block; its context and any following
+        # "note:" lines (and their context) belong to it.
+        if ERROR_RE.search(line):
+            flush()
+            current = []
+        current.append(line)
+    flush()
+
+    return blocks
+
+
+def summarize(blocks: list[str]) -> Counter[str]:
+    """Count unique errors per check name (e.g. "bugprone-branch-clone")."""
+    counts: Counter[str] = Counter()
+    for block in blocks:
+        # The error line is the first line of the block.
+        match = CHECK_RE.search(block.splitlines()[0])
+        if match:
+            counts[match.group(1)] += 1
+    return counts
+
+
+def main() -> int:
+    if len(sys.argv) > 1 and sys.argv[1] != "-":
+        with open(sys.argv[1], encoding="utf-8") as f:
+            lines = f.readlines()
+    else:
+        lines = sys.stdin.readlines()
+
+    blocks = filter_and_dedup(lines)
+    # Blank line between blocks so distinct errors are easy to tell apart.
+    sys.stdout.write("\n".join(blocks))
+
+    print("\nUnique errors per check:", file=sys.stderr)
+    for check, count in summarize(blocks).most_common():
+        print(f"{count:>4} {check}", file=sys.stderr)
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())

bin/install-sanitizer-libs.sh

@@ -0,0 +1,113 @@
+#!/bin/bash
+# Install sanitizer runtime libraries required to run binaries compiled with:
+#   -fsanitize=address   → libasan.so.8
+#   -fsanitize=thread    → libtsan.so.2
+#   -fsanitize=undefined → libubsan.so.1
+#
+# The exact SONAMEs required depend on the compiler toolchain used to build the
+# test binaries (see nix/ci-env.nix). If the toolchain is bumped and SONAMEs
+# change, update the list below (or detect them from the binaries).
+#
+# Supported base images:
+#   debian:bookworm
+#   ubuntu:20.04
+#   rhel:9
+#   nixos/nix        — tests are skipped; this script is not called
+
+set -euo pipefail
+
+if [ ! -f /etc/os-release ]; then
+    echo "ERROR: /etc/os-release not found; cannot detect OS" >&2
+    exit 1
+fi
+
+# shellcheck source=/dev/null
+. /etc/os-release
+
+echo "Detected OS: ${ID} ${VERSION_ID:-}"
+
+case "${ID}" in
+    ubuntu | debian | rhel | centos | rocky | almalinux)
+        echo "Supported OS detected: ${ID}"
+        ;;
+    *)
+        echo "ERROR: unsupported OS '${ID}'. Supported: debian, ubuntu, rhel-family" >&2
+        exit 1
+        ;;
+esac
+
+function preinstall() {
+    case "${ID}" in
+        ubuntu)
+            apt-get update -y
+            apt-get install -y --no-install-recommends \
+                gnupg \
+                software-properties-common
+            add-apt-repository -y ppa:ubuntu-toolchain-r/test
+            ;;
+    esac
+}
+
+function install() {
+    case "${ID}" in
+        debian | ubuntu)
+            apt-get update -y
+            apt-get install -y --no-install-recommends \
+                libasan8 \
+                libtsan2 \
+                libubsan1
+            ;;
+
+        rhel | centos | rocky | almalinux)
+            dnf install -y \
+                libasan8 \
+                libtsan2 \
+                libubsan
+            ;;
+    esac
+}
+
+function postinstall() {
+    # Don't clear cache in non-CI environments
+    if [ -z "${CI:-}" ]; then
+        echo "Not running in CI environment; skipping cache cleanup"
+        return
+    fi
+
+    case "${ID}" in
+        debian | ubuntu)
+            apt-get clean
+            rm -rf /var/lib/apt/lists/*
+            ;;
+
+        rhel | centos | rocky | almalinux)
+            dnf clean -y all
+            rm -rf /var/cache/dnf/*
+            ;;
+    esac
+}
+
+function verify() {
+    # Verify that every expected library is now resolvable by the dynamic linker.
+    missing=0
+    for lib in libasan.so.8 libtsan.so.2 libubsan.so.1; do
+        if ldconfig -p | grep -q "${lib}"; then
+            echo "OK: ${lib} found"
+        else
+            echo "ERROR: ${lib} not found after installation" >&2
+            missing=$((missing + 1))
+        fi
+    done
+
+    if [ "${missing}" -ne 0 ]; then
+        echo "ERROR: ${missing} library/libraries missing" >&2
+        exit 1
+    fi
+}
+
+preinstall
+install
+postinstall
+verify
+
+echo "All sanitizer runtime libraries installed successfully."

bin/pre-commit/Dockerfile

@@ -0,0 +1,55 @@
+ARG BASE_IMAGE=ubuntu:26.04
+
+FROM ${BASE_IMAGE}
+
+SHELL ["/bin/bash", "-e", "-o", "pipefail", "-c"]
+ENTRYPOINT ["/bin/bash"]
+
+ARG DEBIAN_FRONTEND=noninteractive
+
+RUN <<EOF
+pkgs=()
+pkgs+=(curl)         # Required to install nix.
+pkgs+=(doxygen)      # Needed for Clio's check-doxygen-docs.sh.
+pkgs+=(git)          # Required for prepare-runner.
+pkgs+=(libatomic1)   # Required to run pre-commit provided `node`.
+pkgs+=(python3)      # Python 3 interpreter.
+pkgs+=(python3-pip)  # Package manager for Python applications.
+pkgs+=(xz-utils)     # Required to install nix
+
+apt-get update
+apt-get install -y --no-install-recommends "${pkgs[@]}"
+apt-get clean
+rm -rf /var/lib/apt/lists/*
+EOF
+
+ARG PRE_COMMIT_VERSION=4.6.0
+RUN pip install --no-cache --break-system-packages \
+    pre-commit==${PRE_COMMIT_VERSION}
+
+RUN sh <(curl --proto '=https' --tlsv1.2 -L https://nixos.org/nix/install) --daemon --yes
+
+# Add nix to PATH and set NIX environment variables,
+# so nix is available in all shells including non-interactive shells (e.g., GitHub Actions).
+ENV PATH="/nix/var/nix/profiles/default/bin:${PATH}"
+ENV NIX_PROFILES="/nix/var/nix/profiles/default"
+ENV NIX_SSL_CERT_FILE="/nix/var/nix/profiles/default/etc/ssl/certs/ca-bundle.crt"
+
+# Verify nix installation
+RUN nix --version
+
+ENV RUSTUP_HOME="/opt/rust/rustup"
+ENV CARGO_HOME="/opt/rust/cargo"
+ENV PATH="/opt/rust/cargo/bin:${PATH}"
+
+WORKDIR /tmp
+COPY rust-toolchain.toml /tmp/rust-toolchain.toml
+RUN <<EOF
+curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs \
+    | sh -s -- -y --no-modify-path --profile minimal --default-toolchain none
+rustup toolchain install
+rustup show
+cargo fmt --version
+EOF
+
+WORKDIR /

bin/pre-commit/check_doxygen_style.py

@@ -0,0 +1,440 @@
+#!/usr/bin/env python3
+"""
+Check C++ Doxygen comment style.
+
+Enforces the house convention for documentation comments:
+
+  * Use ``/** ... */`` blocks, not ``///``, ``//!`` or ``/*! ... */``; a plain
+    ``/* ... */`` that contains Doxygen commands is a doc comment missing its
+    second star. Trailing member-after comments use ``///<`` (not ``//!<``,
+    ``/*!< ... */`` or ``/**< ... */`` -- the block forms get reflowed and
+    mis-attached by clang-format on packed enum values, the line form does not).
+  * ``/**`` sits alone on its line; the closing ``*/`` sits alone on its line.
+  * Every content line is prefixed with `` * `` (no bare-indented continuation).
+  * The first content line is flush (not over-indented).
+  * Doxygen commands use the ``@cmd`` form, not ``\\cmd``.
+  * Use ``@return`` / ``@throws`` rather than prose ``Returns:`` / ``Throws:``.
+  * A plain ``//`` comment carrying a block-level ``@command`` (``@param``,
+    ``@return``, ``@see``, ...) is documentation and must be a ``/** ... */``
+    block (Doxygen ignores ``//``).
+  * Use canonical command spellings: ``@return`` (not ``@returns``),
+    ``@throws`` (not ``@throw``), ``@see`` (not ``@sa``).
+  * Order block tags ``@tparam`` -> ``@param`` -> ``@return``. (Whether
+    ``@param`` order matches the signature is not checked here -- too fragile to
+    parse; Doxygen's WARN_IF_DOC_ERROR covers name mismatches.)
+  * One-liners are expanded to three lines, EXCEPT bare markers ``@{`` / ``@}``
+    / ``@cond [label]`` / ``@endcond`` / ``@file [name]`` which stay on one line.
+
+Left intentionally alone (recognized, valid Doxygen that is not this style's
+concern):
+
+  * ``///<`` trailing "member-after" comments (the house form).
+  * Divider lines made only of slashes (``//////////``).
+  * Plain ``/* ... */`` (non-Doxygen) comments.
+
+Usage:
+    check_doxygen_style.py [FILE ...]      # explicit files
+    check_doxygen_style.py                 # default: src/ and include/ trees
+
+Exit status is non-zero if any violation is found.
+"""
+
+import argparse
+import re
+import sys
+from collections.abc import Iterable, Iterator
+from dataclasses import dataclass
+from enum import Enum
+from pathlib import Path
+
+
+class Category(Enum):
+    """A kind of style violation: a printed ``label`` and its ``description``.
+
+    The description is the default message; a few categories whose wording
+    depends on the offending text (see ``Finding.detail``) override it.
+    """
+
+    def __init__(self, label: str, description: str) -> None:
+        self.label = label
+        self.description = description
+
+    BACKSLASH_COMMAND = ("backslash-command", "use the @cmd form, not \\cmd")
+    WRONG_COMMAND = ("wrong-command", "use the canonical command spelling")
+    TRIPLE_SLASH = ("triple-slash", "use a /** ... */ block instead of ///")
+    QT_MEMBER = ("qt-member", "use ///< instead of //!<")
+    QT_LINE = ("qt-line", "use a /** ... */ block instead of //!")
+    BLOCK_MEMBER = ("block-member", "use ///< instead of /**<")
+    QT_BLOCK_MEMBER = ("qt-block-member", "use ///< instead of /*!<")
+    DOC_IN_LINE_COMMENT = (
+        "doc-in-line-comment",
+        "use a /** ... */ block for documentation, not //",
+    )
+    QT_COMMENT = ("qt-comment", "use /** instead of /*!")
+    SINGLE_LINE_BLOCK = (
+        "single-line-block",
+        "expand one-line /** ... */ to a multi-line block "
+        "(markers @{ @} @cond @endcond @file may stay)",
+    )
+    TEXT_ON_OPENER = ("text-on-opener", "move text off the /** opener line")
+    BARE_CONTINUATION = ("bare-continuation", 'prefix continuation lines with " * "')
+    OVER_INDENTED = ("over-indented", "first content line is over-indented")
+    OVER_INDENTED_TAG = (
+        "over-indented-tag",
+        'Doxygen tag over-indented; use a single space after "*"',
+    )
+    COMBINED_MARKER = (
+        "combined-marker",
+        "scope marker @{ / @} should be its own single-line /** @{ */ block",
+    )
+    PROSE_LABEL = ("prose-label", "use a Doxygen tag instead of a prose label")
+    CONTENT_ON_CLOSER = ("content-on-closer", "move content off the closing */ line")
+    PLAIN_BLOCK_DOC = (
+        "plain-block-doc",
+        "documentation comment must open with /** not /*",
+    )
+    TAG_ORDER = (
+        "tag-order",
+        "block tags out of order; expected @tparam, then @param, then @return",
+    )
+
+
+@dataclass(frozen=True)
+class Finding:
+    """A single style violation at a 1-based line number.
+
+    ``detail`` overrides the category's default description when the message
+    depends on the offending text (e.g. which command was misspelled).
+    """
+
+    line: int
+    category: Category
+    detail: str | None = None
+
+    @property
+    def message(self) -> str:
+        return self.detail if self.detail is not None else self.category.description
+
+
+DEFAULT_ROOTS = ("src", "include")
+EXTS = {".h", ".hpp", ".cpp", ".ipp", ".cxx", ".cc"}
+
+# Every Doxygen command we recognize when written with a backslash (\cmd).
+_ALL_COMMANDS = (
+    "brief|param|tparam|return|returns|retval|note|warning|pre|post|see|sa|ref|"
+    "throw|throws|exception|deprecated|details|code|endcode|verbatim|endverbatim|"
+    "li|arg|c|internal|since|todo|attention|remark|remarks|ingroup|defgroup"
+)
+# Block-level tags whose over-indentation we flag inside a block body.
+_BLOCK_TAGS = (
+    "param|tparam|returns?|retval|brief|throws?|note|warning|"
+    "pre|post|see|sa|details|deprecated"
+)
+# Tags that, appearing anywhere in a comment, mark it as documentation.
+_ANY_DOC_TAGS = (
+    "param|tparam|returns?|retval|brief|throws?|note|warning|pre|post|see|sa"
+)
+# Tags that make a plain // comment a mis-styled doc comment.
+_LINE_DOC_TAGS = "brief|param|tparam|returns?|retval|throws?|note|see|pre|post"
+
+# \cmd that should be @cmd.
+RE_BACKSLASH_CMD = re.compile(r"\\(" + _ALL_COMMANDS + r")\b")
+# Bare markers that may legitimately stay on a single line.
+RE_MARKER = re.compile(r"^@(\{|\}|cond(\s.*)?|endcond|file(\s.*)?)$")
+# Prose section labels that should be Doxygen tags.
+RE_PROSE_LABEL = re.compile(r"^\*\s(Returns|Throws|Exceptions):\s*$")
+# An over-indented block tag: "*" followed by 2+ spaces then the tag.
+RE_OVERINDENTED_TAG = re.compile(r"^\*\s{2,}@(" + _BLOCK_TAGS + r")\b")
+# Any documentation tag (used to spot a doc comment hiding in a plain /* */).
+RE_ANY_DOC_TAG = re.compile(r"@(" + _ANY_DOC_TAGS + r")\b")
+# A documentation tag inside a // comment.
+RE_LINE_DOC_TAG = re.compile(r"@(" + _LINE_DOC_TAGS + r")\b")
+# Order-relevant tags, for the @tparam -> @param -> @return ordering check.
+RE_ORDER_TAG = re.compile(r"^\*\s*@(param|tparam|returns?|retval)\b")
+# First content line indented by 2+ spaces after the "*".
+RE_FIRST_OVERINDENT = re.compile(r"^\s*\*\s{2,}\S")
+# A scope marker @{ / @} sharing a comment with other text.
+RE_COMBINED_MARKER = re.compile(r"^\*\s*@[{}]\s*$")
+
+# Non-canonical command spellings -> the house spelling (bare command names).
+# Used both to flag a wrong @form and to suggest the right @form for a \wrong.
+CANONICAL_COMMAND = {"returns": "return", "throw": "throws", "sa": "see"}
+WRONG_SPELLINGS = [
+    (re.compile(rf"@{wrong}\b"), f"@{right}")
+    for wrong, right in CANONICAL_COMMAND.items()
+]
+
+# Order block tags should appear in; a body out of this order is a violation.
+EXPECTED_TAG_ORDER = ("tparam", "param", "return")
+
+
+def is_doxy_open(stripped: str) -> bool:
+    """True for a line-start Doxygen block opener we should normalize."""
+    if stripped.startswith("/*!"):  # Qt-style Doxygen
+        return not stripped.startswith("/*!<")  # member-after, leave inline
+    return (
+        stripped.startswith("/**")
+        and not stripped.startswith("/***")
+        and not stripped.startswith("/**/")
+        and not stripped.startswith("/**<")
+    )
+
+
+def _flag_commands(raw_line: str, stripped: str, index: int) -> list[Finding]:
+    """Flag \\cmd and misspelled @cmd on a comment line (opener, body, or closer)."""
+    if not stripped.startswith(("*", "//", "/*")):
+        return []
+    findings: list[Finding] = []
+    backslash = RE_BACKSLASH_CMD.search(raw_line)
+    if backslash:
+        command = backslash.group(1)
+        canonical = CANONICAL_COMMAND.get(command, command)
+        findings.append(
+            Finding(
+                index + 1,
+                Category.BACKSLASH_COMMAND,
+                f"use @{canonical} instead of \\{command}",
+            )
+        )
+    for pattern, replacement in WRONG_SPELLINGS:
+        wrong = pattern.search(raw_line)
+        if wrong:
+            findings.append(
+                Finding(
+                    index + 1,
+                    Category.WRONG_COMMAND,
+                    f"use {replacement} instead of {wrong.group(0)}",
+                )
+            )
+    return findings
+
+
+def _flag_line_comment(raw_line: str, stripped: str, index: int) -> Finding | None:
+    """Return the finding for a single-line comment form (///, //!, /**<, ...), else None."""
+    if stripped.startswith("///") and not stripped.startswith(("////", "///<")):
+        return Finding(index + 1, Category.TRIPLE_SLASH)
+    if "//!<" in raw_line:
+        return Finding(index + 1, Category.QT_MEMBER)
+    if stripped.startswith("//!"):
+        return Finding(index + 1, Category.QT_LINE)
+    if "/**<" in raw_line:
+        return Finding(index + 1, Category.BLOCK_MEMBER)
+    if "/*!<" in raw_line:
+        return Finding(index + 1, Category.QT_BLOCK_MEMBER)
+    if stripped.startswith("//") and RE_LINE_DOC_TAG.search(stripped):
+        return Finding(index + 1, Category.DOC_IN_LINE_COMMENT)
+    return None
+
+
+def _flag_single_line_block(stripped: str, line_no: int, is_qt: bool) -> list[Finding]:
+    """Findings for a whole /** ... */ or /*! ... */ block on one line."""
+    inner = re.sub(r"^/\*[*!]", "", stripped)
+    inner = re.sub(r"\*/\s*$", "", inner).strip()
+    findings: list[Finding] = []
+    if is_qt:
+        findings.append(Finding(line_no, Category.QT_COMMENT))
+    if inner and not RE_MARKER.match(inner):
+        findings.append(Finding(line_no, Category.SINGLE_LINE_BLOCK))
+    return findings
+
+
+def _canonical_order_tag(body: str) -> str | None:
+    """The order-relevant tag (tparam/param/return) a body line opens with, if any."""
+    match = RE_ORDER_TAG.match(body)
+    if match is None:
+        return None
+    command = match.group(1)
+    return "return" if command in ("return", "returns", "retval") else command
+
+
+def _flag_body_line(
+    body_line: str, line_no: int, is_first_content: bool
+) -> list[Finding]:
+    """Findings for one interior line of a multi-line block."""
+    body = body_line.strip()
+    findings: list[Finding] = []
+    if body and not body.startswith("*"):
+        findings.append(Finding(line_no, Category.BARE_CONTINUATION))
+    if body.startswith("*"):
+        if is_first_content and RE_FIRST_OVERINDENT.match(body_line):
+            findings.append(Finding(line_no, Category.OVER_INDENTED))
+        if RE_OVERINDENTED_TAG.match(body):
+            findings.append(Finding(line_no, Category.OVER_INDENTED_TAG))
+        if RE_COMBINED_MARKER.match(body):
+            findings.append(Finding(line_no, Category.COMBINED_MARKER))
+        label = RE_PROSE_LABEL.match(body)
+        if label:
+            suggested_tag = "@return" if label.group(1) == "Returns" else "@throws"
+            findings.append(
+                Finding(
+                    line_no,
+                    Category.PROSE_LABEL,
+                    f'use {suggested_tag} instead of prose "{label.group(1)}:"',
+                )
+            )
+    return findings
+
+
+def _flag_closer(closer_line: str, line_no: int) -> list[Finding]:
+    """Findings for content sharing the closing */ line."""
+    before = closer_line[: closer_line.index("*/")].strip()
+    if before and before != "*":
+        return [Finding(line_no, Category.CONTENT_ON_CLOSER)]
+    return []
+
+
+def _flag_tag_order(first_tag_line: dict[str, int]) -> list[Finding]:
+    """One finding if the present block tags are not in EXPECTED_TAG_ORDER."""
+    tag_lines = [
+        first_tag_line[tag] for tag in EXPECTED_TAG_ORDER if tag in first_tag_line
+    ]
+    if tag_lines != sorted(tag_lines):
+        return [Finding(min(tag_lines), Category.TAG_ORDER)]
+    return []
+
+
+def _flag_doxy_block(lines: list[str], start: int) -> tuple[int, list[Finding]]:
+    """Handle a /** or /*! block opening at ``start``; return (next index, findings)."""
+    raw_line = lines[start]
+    stripped = raw_line.lstrip()
+    open_pos = raw_line.index("/*")
+    is_qt = stripped.startswith("/*!")
+
+    # A whole block on one line: /** ... */.
+    if "*/" in raw_line[open_pos + 2 :]:
+        return start + 1, _flag_single_line_block(stripped, start + 1, is_qt)
+
+    # Multi-line block: opener, then scan the body to the closer.
+    findings: list[Finding] = []
+    if is_qt:
+        findings.append(Finding(start + 1, Category.QT_COMMENT))
+    if raw_line[open_pos + 3 :].strip():
+        findings.append(Finding(start + 1, Category.TEXT_ON_OPENER))
+
+    line_count = len(lines)
+    cursor = start + 1
+    is_first_content = True
+    first_tag_line: dict[str, int] = {}  # canonical tag -> 1-based first line
+    while cursor < line_count and "*/" not in lines[cursor]:
+        body_line = lines[cursor]
+        body = body_line.strip()
+        findings.extend(_flag_commands(body_line, body, cursor))
+        tag = _canonical_order_tag(body)
+        if tag is not None:
+            first_tag_line.setdefault(tag, cursor + 1)
+        findings.extend(_flag_body_line(body_line, cursor + 1, is_first_content))
+        if body.startswith("*"):
+            is_first_content = False
+        cursor += 1
+
+    if cursor < line_count:
+        closer_line = lines[cursor]
+        findings.extend(_flag_commands(closer_line, closer_line.strip(), cursor))
+        findings.extend(_flag_closer(closer_line, cursor + 1))
+    findings.extend(_flag_tag_order(first_tag_line))
+
+    return cursor + 1, findings
+
+
+def _flag_plain_block(lines: list[str], start: int) -> tuple[int, list[Finding]]:
+    """Handle a line-start plain /* ... */ block; return (next index, findings).
+
+    Only flagged when it hides a documentation command (a missing second star).
+    """
+    line_count = len(lines)
+    cursor = start
+    while cursor < line_count and "*/" not in lines[cursor]:
+        cursor += 1
+    findings: list[Finding] = []
+    # The opener (start) is command-checked by check_file; check the rest here.
+    for i in range(start + 1, min(cursor + 1, line_count)):
+        findings.extend(_flag_commands(lines[i], lines[i].strip(), i))
+    block_text = "\n".join(
+        lines[start : cursor + 1] if cursor < line_count else lines[start:]
+    )
+    if RE_ANY_DOC_TAG.search(block_text):
+        findings.append(Finding(start + 1, Category.PLAIN_BLOCK_DOC))
+    next_index = cursor + 1 if cursor < line_count else line_count
+    return next_index, findings
+
+
+def check_source(text: str) -> list[Finding]:
+    """Return all style violations found in the given source text."""
+    lines = text.split("\n")
+    findings: list[Finding] = []
+    line_count = len(lines)
+    index = 0
+    in_plain_block = False  # inside a mid-line, non-Doxygen /* ... */
+    while index < line_count:
+        raw_line = lines[index]
+        stripped = raw_line.lstrip()
+
+        # Skip the interior of a plain block opened on an earlier line.
+        if in_plain_block:
+            in_plain_block = "*/" not in raw_line
+            index += 1
+            continue
+
+        findings.extend(_flag_commands(raw_line, stripped, index))
+
+        line_finding = _flag_line_comment(raw_line, stripped, index)
+        if line_finding is not None:
+            findings.append(line_finding)
+            index += 1
+        elif is_doxy_open(stripped):
+            index, block_findings = _flag_doxy_block(lines, index)
+            findings.extend(block_findings)
+        elif stripped.startswith("/*"):
+            index, block_findings = _flag_plain_block(lines, index)
+            findings.extend(block_findings)
+        else:
+            # A /* that opens mid-line without closing starts a plain block.
+            if "/*" in raw_line and not stripped.startswith("//"):
+                if "*/" not in raw_line[raw_line.index("/*") + 2 :]:
+                    in_plain_block = True
+            index += 1
+    return findings
+
+
+def check_file(path: Path) -> list[Finding]:
+    """Return all style violations found in one file."""
+    return check_source(path.read_text(encoding="utf-8"))
+
+
+def iter_files(paths: Iterable[str]) -> Iterator[Path]:
+    """Yield every C++ source file among the given files and directories."""
+    for raw_path in paths:
+        path = Path(raw_path)
+        if path.is_dir():
+            for candidate in path.rglob("*"):
+                if candidate.is_file() and candidate.suffix in EXTS:
+                    yield candidate
+        elif path.suffix in EXTS:
+            yield path
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Check Doxygen comment style.")
+    parser.add_argument(
+        "files", nargs="*", help="files or directories (default: src/ include/)"
+    )
+    parser.add_argument(
+        "-q", "--quiet", action="store_true", help="only print the summary count"
+    )
+    args = parser.parse_args()
+    roots = args.files or [root for root in DEFAULT_ROOTS if Path(root).is_dir()]
+
+    total = 0
+    for path in sorted(set(iter_files(roots)), key=str):
+        for finding in check_file(path):
+            total += 1
+            if not args.quiet:
+                print(
+                    f"{path}:{finding.line}: {finding.category.label}: {finding.message}"
+                )
+    print(f"\n{total} doxygen-style violation(s)", file=sys.stderr)
+    return 1 if total else 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())

bin/pre-commit/clang_tidy_check.py

@@ -1,24 +1,46 @@
 #!/usr/bin/env python3
-"""Pre-commit hook that runs clang-tidy on changed files using run-clang-tidy."""
+"""Pre-commit hook that runs clang-tidy on staged files using run-clang-tidy.
+
+The script determines the staged files itself (see `pass_filenames: false` in
+.pre-commit-config.yaml) so run-clang-tidy is run once and handles parallelism
+internally: pre-commit would otherwise split the files across parallel hook
+invocations that race when fixes edit a shared header.
+
+Fixes are collected with `-export-fixes` and applied by clang-apply-replacements
+in a separate step rather than with run-clang-tidy's `-fix`. The `add_module`
+build isolates each module's headers behind a per-module symlink directory
+(build/modules/<module>/...), so a header reachable from several translation
+units is referenced through different paths that all resolve to the same source
+file. clang-apply-replacements deduplicates identical replacements by their
+literal path, so those paths must be canonicalised to the real source path
+first; otherwise the same fix is applied once per path and corrupts the header.
+"""
 
 from __future__ import annotations
 
-import json
 import os
 import re
 import shutil
 import subprocess
 import sys
-from collections import defaultdict
+import tempfile
 from pathlib import Path
 
-HEADER_EXTENSIONS = {".h", ".hpp", ".ipp"}
-SOURCE_EXTENSIONS = {".cpp"}
-INCLUDE_RE = re.compile(r"^\s*#\s*include\s*[<\"]([^>\"]+)[>\"]")
+CLANG_TIDY_VERSION = 22
+
+# Extensions run-clang-tidy can analyse: `.cpp` translation units and, thanks to
+# the `verify_headers` build option, `.h`/`.hpp` headers (each has its own
+# compile_commands.json entry). `.ipp` fragments have no entry and are skipped.
+TIDY_EXTENSIONS = {".cpp", ".h", ".hpp"}
+
+# A single-quoted `FilePath:` entry in an -export-fixes YAML file, allowing the
+# `- ` marker that precedes it inside a `Replacements:` sequence. clang-tidy
+# emits paths single-quoted and doubles any embedded quote per YAML rules.
+FILEPATH_RE = re.compile(r"^(\s*(?:-\s+)?FilePath:\s*)'((?:[^']|'')*)'\s*$")
 
 
-def find_run_clang_tidy() -> str | None:
-    for candidate in ("run-clang-tidy-21", "run-clang-tidy"):
+def find_tool(name: str) -> str | None:
+    for candidate in (f"{name}-{CLANG_TIDY_VERSION}", name):
         if path := shutil.which(candidate):
             return path
     return None
@@ -32,136 +54,37 @@ def find_build_dir(repo_root: Path) -> Path | None:
     return None
 
 
-def build_include_graph(build_dir: Path, repo_root: Path) -> tuple[dict, set]:
+def staged_files(repo_root: Path) -> list[Path]:
+    """Return absolute paths of staged, lint-able C/C++ files.
+
+    `--diff-filter=d` excludes deletions so we never lint a removed file.
     """
-    Scan all files reachable from compile_commands.json and build an inverted include graph.
-
-    Returns:
-        inverted: header_path -> set of files that include it
-        source_files: set of all TU paths from compile_commands.json
-    """
-    with open(build_dir / "compile_commands.json") as f:
-        db = json.load(f)
-
-    source_files = {Path(e["file"]).resolve() for e in db}
-    include_roots = [repo_root / "include", repo_root / "src"]
-    inverted: dict[Path, set[Path]] = defaultdict(set)
-
-    to_scan: set[Path] = set(source_files)
-    scanned: set[Path] = set()
-
-    while to_scan:
-        file = to_scan.pop()
-        if file in scanned or not file.exists():
-            continue
-        scanned.add(file)
-
-        content = file.read_text()
-
-        for line in content.splitlines():
-            m = INCLUDE_RE.match(line)
-            if not m:
-                continue
-            for root in include_roots:
-                candidate = (root / m.group(1)).resolve()
-                if candidate.exists():
-                    inverted[candidate].add(file)
-                    if candidate not in scanned:
-                        to_scan.add(candidate)
-                    break
-
-    return inverted, source_files
-
-
-def find_tus_for_headers(
-    headers: list[Path],
-    inverted: dict[Path, set[Path]],
-    source_files: set[Path],
-) -> set[Path]:
-    """
-    For each header, pick one TU that transitively includes it.
-    Prefers a TU whose stem matches the header's stem, otherwise picks the first found.
-    """
-    result: set[Path] = set()
-
-    for header in headers:
-        preferred: Path | None = None
-        visited: set[Path] = {header}
-        stack: list[Path] = [header]
-
-        while stack:
-            h = stack.pop()
-            for inc in inverted.get(h, ()):
-                if inc in source_files:
-                    if inc.stem == header.stem:
-                        preferred = inc
-                        break
-                    if preferred is None:
-                        preferred = inc
-                if inc not in visited:
-                    visited.add(inc)
-                    stack.append(inc)
-            if preferred is not None and preferred.stem == header.stem:
-                break
-
-        if preferred is not None:
-            result.add(preferred)
-
-    return result
-
-
-def resolve_files(
-    input_files: list[str], build_dir: Path, repo_root: Path
-) -> list[str]:
-    """
-    Split input into source files and headers. Source files are passed through;
-    headers are resolved to the TUs that transitively include them.
-    """
-    sources: list[Path] = []
-    headers: list[Path] = []
-
-    for f in input_files:
-        p = Path(f).resolve()
-        if p.suffix in SOURCE_EXTENSIONS:
-            sources.append(p)
-        elif p.suffix in HEADER_EXTENSIONS:
-            headers.append(p)
-
-    if not headers:
-        return [str(p) for p in sources]
-
-    print(
-        f"Resolving {len(headers)} header(s) to compilation units...", file=sys.stderr
-    )
-    inverted, source_files = build_include_graph(build_dir, repo_root)
-    tus = find_tus_for_headers(headers, inverted, source_files)
-
-    if not tus:
-        print(
-            "Warning: no compilation units found that include the modified headers; "
-            "skipping clang-tidy for headers.",
-            file=sys.stderr,
-        )
-
-    return sorted({str(p) for p in (*sources, *tus)})
-
-
-def staged_files(repo_root: Path) -> list[str]:
-    result = subprocess.run(
-        ["git", "diff", "--staged", "--name-only", "--diff-filter=d"],
-        capture_output=True,
+    output = subprocess.check_output(
+        ["git", "diff", "--staged", "--name-only", "--diff-filter=d", "--"]
+        + [f"*{ext}" for ext in TIDY_EXTENSIONS],
         text=True,
         cwd=repo_root,
     )
-    if result.returncode != 0:
-        print(
-            "clang-tidy check failed: 'git diff --staged' command failed.",
-            file=sys.stderr,
-        )
-        if result.stderr:
-            print(result.stderr, file=sys.stderr)
-        sys.exit(result.returncode or 1)
-    return [str(repo_root / p) for p in result.stdout.splitlines() if p]
+    return [repo_root / rel for rel in output.splitlines() if rel]
+
+
+def canonicalize_fix_paths(fixes_dir: Path) -> None:
+    """Rewrite every `FilePath` in the exported fixes to its real source path.
+
+    A header included through a module's isolation symlink is recorded under that
+    symlink's path; collapsing all paths to the same real file lets
+    clang-apply-replacements recognise the per-translation-unit duplicates and
+    apply each fix once.
+    """
+    for yaml in fixes_dir.glob("*.yaml"):
+        lines = []
+        for line in yaml.read_text().splitlines():
+            if m := FILEPATH_RE.match(line):
+                path = m.group(2).replace("''", "'")
+                real = os.path.realpath(path).replace("'", "''")
+                line = f"{m.group(1)}'{real}'"
+            lines.append(line)
+        yaml.write_text("\n".join(lines) + "\n")
 
 
 def main():
@@ -175,15 +98,25 @@ def main():
             text=True,
         ).strip()
     )
+
     files = staged_files(repo_root)
     if not files:
         return 0
 
-    run_clang_tidy = find_run_clang_tidy()
-    if not run_clang_tidy:
+    run_clang_tidy = find_tool("run-clang-tidy")
+    clang_apply_replacements = find_tool("clang-apply-replacements")
+    missing = [
+        name
+        for name, path in (
+            ("run-clang-tidy", run_clang_tidy),
+            ("clang-apply-replacements", clang_apply_replacements),
+        )
+        if not path
+    ]
+    if missing:
         print(
-            "clang-tidy check failed: TIDY is enabled but neither "
-            "'run-clang-tidy-21' nor 'run-clang-tidy' was found in PATH.",
+            f"clang-tidy check failed: TIDY is enabled but {' and '.join(missing)} "
+            f"was not found in PATH (tried the '-{CLANG_TIDY_VERSION}' suffix too).",
             file=sys.stderr,
         )
         return 1
@@ -197,15 +130,27 @@ def main():
         )
         return 1
 
-    tidy_files = resolve_files(files, build_dir, repo_root)
-    if not tidy_files:
-        return 0
+    with tempfile.TemporaryDirectory() as fixes_dir:
+        result = subprocess.run(
+            [
+                run_clang_tidy,
+                "-quiet",
+                "-p",
+                build_dir,
+                "-export-fixes",
+                fixes_dir,
+                "-allow-no-checks",
+            ]
+            + files
+        )
+        canonicalize_fix_paths(Path(fixes_dir))
+        # `FormatStyle` in .clang-tidy does not reach this path,
+        # so ask for the repository style here.
+        applied = subprocess.run(
+            [clang_apply_replacements, "--format", "--style=file", fixes_dir]
+        )
 
-    result = subprocess.run(
-        [run_clang_tidy, "-quiet", "-p", str(build_dir), "-fix", "-allow-no-checks"]
-        + tidy_files
-    )
-    return result.returncode
+    return result.returncode or applied.returncode
 
 
 if __name__ == "__main__":

bin/pre-commit/fix_pragma_once.py

@@ -0,0 +1,34 @@
+#!/usr/bin/env python3
+
+"""
+Adds "#pragma once" to the top of header files that don't already have it.
+
+Usage: ./bin/pre-commit/fix_pragma_once.py <file1> <file2> ...
+"""
+
+import sys
+from pathlib import Path
+
+PRAGMA_ONCE = "#pragma once\n\n"
+
+
+def fix_pragma_once(path: Path) -> bool:
+    original = path.read_text(encoding="utf-8")
+    if PRAGMA_ONCE not in original:
+        path.write_text(PRAGMA_ONCE + original, encoding="utf-8")
+        return False
+    return True
+
+
+def main() -> int:
+    files = [Path(f) for f in sys.argv[1:]]
+    success = True
+
+    for path in files:
+        success &= fix_pragma_once(path)
+
+    return 0 if success else 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())

bin/pre-commit/test_check_doxygen_style.py

@@ -0,0 +1,406 @@
+#!/usr/bin/env python3
+"""
+Tests for check_doxygen_style.py.
+
+Run directly (no test framework needed):
+    ./bin/pre-commit/test_check_doxygen_style.py
+or under pytest:
+    pytest bin/pre-commit/test_check_doxygen_style.py
+"""
+
+import sys
+import textwrap
+
+from check_doxygen_style import Finding, check_source
+
+
+def findings_for(text: str) -> list[Finding]:
+    """Return the style violations for the given source text.
+
+    The text is dedented and its leading newline stripped, so fixtures can be
+    written as indented triple-quoted here-docs while keeping honest 1-based
+    line numbers.
+    """
+    text = textwrap.dedent(text).lstrip("\n")
+    return check_source(text)
+
+
+def labels_for(text: str) -> list[str]:
+    return [f.category.label for f in findings_for(text)]
+
+
+def messages_for(text: str) -> list[str]:
+    return [f.message for f in findings_for(text)]
+
+
+# --- well-formed input produces nothing -------------------------------------
+
+
+def test_clean_block_ok() -> None:
+    code = """
+    /**
+     * Brief.
+     *
+     * @tparam T a type
+     * @param x the x
+     * @return the result
+     */
+    """
+    assert findings_for(code) == []
+
+
+def test_blank_lines_inside_block_ok() -> None:
+    code = """
+    /**
+     * a
+     *
+     * b
+     */
+    """
+    assert findings_for(code) == []
+
+
+def test_member_and_divider_allowed() -> None:
+    assert findings_for("int x;  ///< ok member\n") == []
+    assert findings_for("//////////\n") == []
+    assert findings_for("//// text\n") == []
+
+
+# --- line-comment forms ------------------------------------------------------
+
+
+def test_triple_slash() -> None:
+    code = "/// doc\n"
+    assert labels_for(code) == ["triple-slash"]
+
+
+def test_qt_line() -> None:
+    code = "//! doc\n"
+    assert labels_for(code) == ["qt-line"]
+
+
+def test_qt_member() -> None:
+    code = "int x;  //!< doc\n"
+    assert labels_for(code) == ["qt-member"]
+
+
+def test_block_member() -> None:
+    code = "int x;  /**< doc */\n"
+    assert labels_for(code) == ["block-member"]
+
+
+def test_qt_block_member() -> None:
+    code = "int x;  /*!< doc */\n"
+    assert labels_for(code) == ["qt-block-member"]
+
+
+def test_doc_in_line_comment() -> None:
+    code = "// @param x\n"
+    assert labels_for(code) == ["doc-in-line-comment"]
+
+
+# --- block forms -------------------------------------------------------------
+
+
+def test_qt_comment() -> None:
+    code = """
+    /*!
+     * brief
+     */
+    """
+    assert labels_for(code) == ["qt-comment"]
+
+
+def test_qt_comment_single_line() -> None:
+    # /*! ... */ on one line -> qt-comment (plus single-line-block)
+    code = "/*! brief */\n"
+    assert labels_for(code) == ["qt-comment", "single-line-block"]
+
+
+def test_single_line_block() -> None:
+    code = "/** brief */\n"
+    assert labels_for(code) == ["single-line-block"]
+
+
+def test_single_line_markers_allowed() -> None:
+    for marker in ("@{", "@}", "@cond LABEL", "@endcond", "@file foo.h"):
+        code = f"/** {marker} */\n"
+        assert findings_for(code) == [], marker
+
+
+def test_text_on_opener() -> None:
+    code = """
+    /** text here
+     * more
+     */
+    """
+    assert labels_for(code) == ["text-on-opener"]
+
+
+def test_bare_continuation() -> None:
+    code = """
+    /**
+     * a
+       bare line
+     */
+    """
+    assert labels_for(code) == ["bare-continuation"]
+
+
+def test_over_indented_first_line() -> None:
+    code = """
+    /**
+     *   over
+     */
+    """
+    assert labels_for(code) == ["over-indented"]
+
+
+def test_over_indented_tag() -> None:
+    # a flush first line consumes "first content", isolating the tag check
+    code = """
+    /**
+     * brief
+     *   @param x
+     */
+    """
+    assert labels_for(code) == ["over-indented-tag"]
+
+
+def test_combined_marker() -> None:
+    code = """
+    /**
+     * @{
+     */
+    """
+    assert labels_for(code) == ["combined-marker"]
+
+
+def test_prose_label() -> None:
+    for word in ("Returns", "Throws", "Exceptions"):
+        code = f"""
+        /**
+         * {word}:
+         */
+        """
+        assert labels_for(code) == ["prose-label"], word
+
+
+def test_content_on_closer() -> None:
+    code = """
+    /**
+     * a
+     * b */
+    """
+    assert labels_for(code) == ["content-on-closer"]
+
+
+def test_plain_block_doc() -> None:
+    assert labels_for("/* @param x */\n") == ["plain-block-doc"]
+    assert findings_for("/* just an ordinary note */\n") == []
+
+
+def test_tag_order() -> None:
+    out_of_order = """
+    /**
+     * @param x
+     * @tparam T
+     */
+    """
+    assert labels_for(out_of_order) == ["tag-order"]
+
+    correct = """
+    /**
+     * @tparam T
+     * @param x
+     * @return r
+     */
+    """
+    assert findings_for(correct) == []
+
+    single = """
+    /**
+     * @param x
+     */
+    """
+    assert findings_for(single) == []  # single tag: never out of order
+
+
+# --- command spelling (must work on body/closer lines, not just the opener) --
+
+
+def test_backslash_command_on_body_line() -> None:
+    code = r"""
+    /**
+     * \brief x
+     */
+    """
+    assert labels_for(code) == ["backslash-command"]
+
+
+def test_backslash_command_suggests_canonical_spelling() -> None:
+    # a backslash + non-canonical spelling is fixed in one pass, not two:
+    # \sa -> @see (not @sa), \returns -> @return (not @returns)
+    sa = r"""
+    /**
+     * \sa other
+     */
+    """
+    assert messages_for(sa) == [r"use @see instead of \sa"]
+
+    returns = r"""
+    /**
+     * \returns x
+     */
+    """
+    assert messages_for(returns) == [r"use @return instead of \returns"]
+
+
+def test_wrong_command_on_body_line() -> None:
+    code = """
+    /**
+     * @returns x
+     */
+    """
+    assert labels_for(code) == ["wrong-command"]
+
+
+def test_body_line_commands_regression() -> None:
+    # regression: these live on body lines of a multi-line block
+    code = r"""
+    /**
+     * @returns bad
+     * @throw ex
+     * @sa other
+     * \param y
+     */
+    """
+    assert labels_for(code) == [
+        "wrong-command",
+        "wrong-command",
+        "wrong-command",
+        "backslash-command",
+    ]
+
+
+def test_command_on_closer_line() -> None:
+    code = """
+    /**
+     * a
+     * @sa b */
+    """
+    assert labels_for(code) == ["wrong-command", "content-on-closer"]
+
+
+def test_no_double_count_across_opener_body_closer() -> None:
+    code = """
+    /** @returns opener
+     * @throw body
+     * @sa closer */
+    """
+    assert labels_for(code).count("wrong-command") == 3
+
+
+def test_code_with_word_allowed() -> None:
+    # @code{.cpp} is valid Doxygen and must not be flagged
+    code = """
+    /**
+     * @code{.cpp}
+     * int x;
+     * @endcode
+     */
+    """
+    assert findings_for(code) == []
+
+
+# --- rendered message text ---------------------------------------------------
+
+
+def test_message_uses_category_description() -> None:
+    # a static category renders its default description
+    code = "/// doc\n"
+    assert messages_for(code) == ["use a /** ... */ block instead of ///"]
+
+
+def test_message_detail_overrides() -> None:
+    # dynamic categories render the offending text via Finding.detail
+    backslash = r"""
+    /**
+     * \param y
+     */
+    """
+    assert messages_for(backslash) == [r"use @param instead of \param"]
+
+    wrong = """
+    /**
+     * @returns x
+     */
+    """
+    assert messages_for(wrong) == ["use @return instead of @returns"]
+
+    prose = """
+    /**
+     * Throws:
+     */
+    """
+    assert messages_for(prose) == ['use @throws instead of prose "Throws:"']
+
+
+# --- robustness --------------------------------------------------------------
+
+
+def test_empty_file_no_crash() -> None:
+    assert findings_for("") == []
+
+
+def test_mid_line_plain_block_skipped() -> None:
+    # a /* opened mid-line (after code) and spanning lines is skipped, so its
+    # comment-like contents are not analyzed
+    code = """
+    int x = 0;  /* note: @returns is not a real tag here
+     * @param also not real
+     */
+    int y = 0;
+    """
+    assert findings_for(code) == []
+
+
+def test_unclosed_block_scanned_to_eof() -> None:
+    # an unterminated /** block is still scanned to EOF (no crash, body checked)
+    code = """
+    /**
+     * @returns x
+    """
+    assert labels_for(code) == ["wrong-command"]
+
+
+def test_banner_and_empty_comment_not_flagged() -> None:
+    code = """
+    /***
+     * banner
+     ***/
+    """
+    assert findings_for(code) == []
+    assert findings_for("/**/\n") == []
+
+
+def main() -> int:
+    tests = sorted(
+        (name, fn)
+        for name, fn in globals().items()
+        if name.startswith("test_") and callable(fn)
+    )
+    failed = 0
+    for name, fn in tests:
+        try:
+            fn()
+            print(f"PASS {name}")
+        except AssertionError as exc:
+            failed += 1
+            print(f"FAIL {name}: {exc!r}")
+    print(f"\n{len(tests) - failed}/{len(tests)} passed")
+    return 1 if failed else 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())

cfg/xrpld-example.cfg

@@ -488,6 +488,17 @@
 #   Must be a number between 100 and 1000, defaults to 250
 #
 #
+# [max_subscriptions_per_connection]
+#
+#   Maximum number of account, real-time account, and account-history
+#   subscriptions a single client connection may hold at once. Bounds the
+#   per-connection state torn down when the connection disconnects. Book
+#   subscriptions are tracked separately and are not counted here.
+#
+#   Defaults to 100000 if not set; large enough for legitimate power users
+#   such as block explorers.
+#
+#
 # [overlay]
 #
 #   Controls settings related to the peer to peer overlay.
@@ -538,6 +549,45 @@
 #       only be used for local testing and debugging. Do not disable
 #       on mainnet.
 #
+#   max_untrusted_count = <number>
+#
+#       The number of manifests the server keeps for validators it does not
+#       list, and the number it sends and processes in a single peer protocol
+#       message. Once the server holds this many, a manifest for a new
+#       unlisted validator is rejected, so peer gossip cannot grow the cache
+#       without end.
+#
+#       This option can take any value between 50 and 1000, inclusive. If
+#       the option is not present the server uses its built-in value.
+#
+#       The current default (which is subject to change) is 300.
+#
+#   max_trusted_count = <number>
+#
+#       The number of manifests for listed validators to allow for when
+#       sizing peer protocol messages. Manifests for listed validators are
+#       never dropped, whether sending or receiving, because doing so would
+#       delay a validator key change reaching this server. Set this above the
+#       number of validators the server lists.
+#
+#       Together the two counts above set the largest manifest message the
+#       server accepts: bigger messages are discarded without reading them,
+#       and without penalising the sender. Raising either means the server
+#       accepts and sends bigger messages than a peer using the defaults, and
+#       those peers will discard what this server sends. Lowering either below
+#       what peers send makes this server discard their manifest messages,
+#       which it does without recording anything.
+#
+#       This option can take any value between 50 and 1000, inclusive. If
+#       the option is not present the server uses its built-in value.
+#
+#       The current default (which is subject to change) is 300.
+#
+#       NOTE: These two options (max_untrusted_count and max_trusted_count)
+#       are transitional. They exist to bound manifest-message size and cache
+#       growth during the network upgrade. They may be removed in a future
+#       release once the fleet has upgraded, and should not be relied upon as
+#       stable configuration.
 #
 # [transaction_queue] EXPERIMENTAL
 #

cmake/CompilationEnv.cmake

@@ -29,6 +29,27 @@ if(CMAKE_GENERATOR STREQUAL "Xcode")
     set(is_xcode TRUE)
 endif()
 
+# --------------------------------------------------------------------
+# Nix toolchain detection
+# --------------------------------------------------------------------
+# True when the C++ compiler resolves into the Nix store. CMAKE_CXX_COMPILER may
+# be referenced through a symlink outside the store (a Nix profile, a /usr/bin
+# alternative, ...), so resolve the real path before matching.
+set(is_nix_compiler FALSE)
+get_filename_component(_cxx_real "${CMAKE_CXX_COMPILER}" REALPATH)
+if(_cxx_real MATCHES "^/nix/store/")
+    set(is_nix_compiler TRUE)
+endif()
+unset(_cxx_real)
+
+# True inside the Nix CI Docker image, identified by the /nix/ci-env tree it
+# ships (see nix/docker/Dockerfile). The dev shell and bare systems don't have
+# it, so it distinguishes the CI image from other Nix-compiler environments.
+set(is_ci_image FALSE)
+if(EXISTS "/nix/ci-env/bin")
+    set(is_ci_image TRUE)
+endif()
+
 # --------------------------------------------------------------------
 # Operating system detection
 # --------------------------------------------------------------------
@@ -56,3 +77,16 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|arm64|ARM64")
 else()
     message(FATAL_ERROR "Unknown architecture: ${CMAKE_SYSTEM_PROCESSOR}")
 endif()
+
+# --------------------------------------------------------------------
+# Sanitizers
+# --------------------------------------------------------------------
+# SANITIZERS is injected by the Conan toolchain when a sanitizer build is
+# requested (see conan/profiles/sanitizers). The flags are applied to the
+# 'common' target in XrplSanitizers; this flag lets other modules know a
+# sanitizer build is active without depending on that module.
+if(DEFINED SANITIZERS)
+    set(SANITIZERS_ENABLED TRUE)
+else()
+    set(SANITIZERS_ENABLED FALSE)
+endif()

cmake/PatchNixBinary.cmake

@@ -0,0 +1,90 @@
+#[===================================================================[
+   Patch executables to run in non-Nix environments.
+
+   The Nix toolchain links binaries against an ELF interpreter (loader)
+   that lives in the Nix store, so the resulting binaries don't run elsewhere
+   (including once installed from the .deb package). `patch_nix_binary` resets
+   the interpreter to the system default loader and drops the rpath, once the
+   binary has been linked.
+
+   This runs by default for Nix-toolchain builds (determined by whether the compiler resolves under /nix/store/).
+   Those builds are where binaries get a Nix-store loader.
+   It is opted out of by setting the XRPLD_NO_PATCH_NIX_BINARY environment variable —
+   the plain Nix dev shells set it, since their binaries link a newer glibc
+   and must not be retargeted to the system loader.
+
+   Non-Nix builds (a system compiler, already using the system loader) and sanitizer builds
+   (runtime libraries resolved through the rpath) are skipped too.
+   Everywhere else `patch_nix_binary` is a no-op.
+
+   The default loader is resolved by bin/default-loader-path.sh.
+#]===================================================================]
+
+include_guard(GLOBAL)
+
+include(CompilationEnv)
+
+# Resolves the system default ELF loader path for the current architecture.
+set(_loader_path_script "${CMAKE_SOURCE_DIR}/bin/default-loader-path.sh")
+
+if(
+    is_linux
+    AND NOT SANITIZERS_ENABLED
+    AND is_nix_compiler
+    AND NOT DEFINED ENV{XRPLD_NO_PATCH_NIX_BINARY}
+)
+    execute_process(
+        COMMAND "${_loader_path_script}"
+        OUTPUT_VARIABLE DEFAULT_LOADER_PATH
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+        COMMAND_ERROR_IS_FATAL ANY
+    )
+    find_program(PATCHELF_COMMAND patchelf REQUIRED)
+    set(PATCH_NIX_BINARIES TRUE)
+    message(
+        STATUS
+        "Binaries will be patched to use loader '${DEFAULT_LOADER_PATH}'"
+    )
+else()
+    set(PATCH_NIX_BINARIES FALSE)
+endif()
+
+function(patch_nix_binary target)
+    if(NOT PATCH_NIX_BINARIES)
+        return()
+    endif()
+
+    set(patch_command
+        "${PATCHELF_COMMAND}"
+        --set-interpreter
+        "${DEFAULT_LOADER_PATH}"
+        --remove-rpath
+        "$<TARGET_FILE:${target}>"
+    )
+    set(comment "Patching ${target}: set default loader, remove rpath")
+
+    # POST_BUILD is the cheap way to do this: it runs only when the binary is
+    # relinked. It is also only available in the directory that defined the
+    # target, so for a target from elsewhere (e.g. a FetchContent subproject)
+    # fall back to a custom target that runs after the binary is linked. That
+    # one runs on every build, which is harmless because patchelf is idempotent.
+    get_target_property(target_source_dir ${target} SOURCE_DIR)
+    if("${target_source_dir}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
+        add_custom_command(
+            TARGET ${target}
+            POST_BUILD
+            COMMAND ${patch_command}
+            COMMENT "${comment}"
+            VERBATIM
+        )
+    else()
+        add_custom_target(
+            ${target}-patch-nix
+            ALL
+            COMMAND ${patch_command}
+            COMMENT "${comment}"
+            VERBATIM
+        )
+        add_dependencies(${target}-patch-nix ${target})
+    endif()
+endfunction()

cmake/XrplAddBenchmark.cmake

@@ -0,0 +1,38 @@
+include_guard()
+
+include(isolate_headers)
+
+# Define a benchmark executable for the module `name`.
+#
+# This follows the same general pattern as other build helpers in this repo
+# (e.g. `add_module`): create a target and isolate headers, but here the target
+# is a benchmark executable and no `add_test(...)` is registered.
+#
+# `isolate_headers` exposes only `${CMAKE_CURRENT_SOURCE_DIR}/${name}` on the
+# include path, rooted at `src`, so a benchmark's own headers are reached as
+# `<benchmarks/.../${name}/...>` and nothing else in the tree leaks in.
+function(xrpl_add_benchmark name)
+    set(target ${PROJECT_NAME}.bench.${name})
+
+    file(
+        GLOB_RECURSE sources
+        CONFIGURE_DEPENDS
+        "${CMAKE_CURRENT_SOURCE_DIR}/${name}/*.cpp"
+        "${CMAKE_CURRENT_SOURCE_DIR}/${name}.cpp"
+    )
+    add_executable(${target} ${ARGN} ${sources})
+
+    # Benchmark sources register cases through Google Benchmark's static
+    # registrars (anonymous-namespace lambdas). Merging several such files into
+    # one unity translation unit collides those internal-linkage entities, so
+    # keep benchmarks out of the unity build - mirroring xrpl.libpb in
+    # XrplCore.cmake. Each file compiles fine on its own.
+    set_target_properties(${target} PROPERTIES UNITY_BUILD OFF)
+
+    isolate_headers(
+        ${target}
+        "${CMAKE_SOURCE_DIR}/src"
+        "${CMAKE_CURRENT_SOURCE_DIR}/${name}"
+        PRIVATE
+    )
+endfunction()

cmake/XrplAddTest.cmake

@@ -1,22 +0,0 @@
-include(isolate_headers)
-
-function(xrpl_add_test name)
-    set(target ${PROJECT_NAME}.test.${name})
-
-    file(
-        GLOB_RECURSE sources
-        CONFIGURE_DEPENDS
-        "${CMAKE_CURRENT_SOURCE_DIR}/${name}/*.cpp"
-        "${CMAKE_CURRENT_SOURCE_DIR}/${name}.cpp"
-    )
-    add_executable(${target} ${ARGN} ${sources})
-
-    isolate_headers(
-        ${target}
-        "${CMAKE_SOURCE_DIR}"
-        "${CMAKE_SOURCE_DIR}/tests/${name}"
-        PRIVATE
-    )
-
-    add_test(NAME ${target} COMMAND ${target})
-endfunction()

cmake/XrplCompiler.cmake

@@ -145,13 +145,47 @@ else()
         INTERFACE
             -rdynamic
             $<$<BOOL:${is_linux}>:-Wl,-z,relro,-z,now,--build-id>
-            # link to static libc/c++ iff: * static option set and * NOT APPLE (AppleClang does not support static
-            # libc/c++) and * NOT SANITIZERS (sanitizers typically don't work with static libc/c++)
-            $<$<AND:$<BOOL:${static}>,$<NOT:$<BOOL:${APPLE}>>,$<NOT:$<BOOL:${SANITIZERS_ENABLED}>>>:
+            # link to static libc/c++ if:
+            # * static option set and
+            # * NOT APPLE (AppleClang does not support static libc/c++)
+            $<$<AND:$<BOOL:${static}>,$<NOT:$<BOOL:${APPLE}>>>:
             -static-libstdc++
             -static-libgcc
             >
     )
+
+    # On aarch64, libatomic is required for atomic operations. It is not needed on x86_64.
+    # Linking it statically on Linux
+    if(is_arm64 AND is_linux)
+        target_link_options(
+            common
+            INTERFACE -Wl,--push-state -Wl,-Bstatic -latomic -Wl,--pop-state
+        )
+    endif()
+
+    # Keep -stdlib=libstdc++ off the compile commands, but preserve it for linking.
+    #
+    # Conan turns `compiler.libcxx=libstdc++` into `-stdlib=libstdc++` and puts it in
+    # CMAKE_CXX_FLAGS, which CMake passes to BOTH compile and link steps. On a normal Clang
+    # the compile step consumes it while choosing the C++ stdlib include paths. The Nixpkgs
+    # Clang wrapper supplies those paths itself (via -nostdinc++), so at compile time the
+    # flag is unused -> Clang errors under our -Werror. At link time the flag IS consumed
+    # (it selects the C++ runtime), so we move it there instead of dropping it entirely.
+    if(
+        is_nix_compiler
+        AND is_linux
+        AND is_clang
+        AND CMAKE_CXX_FLAGS MATCHES "stdlib=libstdc"
+    )
+        string(
+            REPLACE "-stdlib=libstdc++"
+            ""
+            CMAKE_CXX_FLAGS
+            "${CMAKE_CXX_FLAGS}"
+        )
+        string(STRIP "${CMAKE_CXX_FLAGS}" CMAKE_CXX_FLAGS)
+        add_link_options($<$<LINK_LANGUAGE:CXX>:-stdlib=libstdc++>)
+    endif()
 endif()
 
 # Antithesis instrumentation will only be built and deployed using machines running Linux.
@@ -232,10 +266,50 @@ elseif(use_lld)
     )
     if("${LD_VERSION}" MATCHES "LLD")
         target_link_libraries(common INTERFACE -fuse-ld=lld)
+        # remembered for the linker flag probe below
+        set(fuse_ld_flag "-fuse-ld=lld")
     endif()
     unset(LD_VERSION)
 endif()
 
+# Linker warnings are errors where we control the toolchain and the dependencies: CI and the Nix dev shell.
+# On non-Nix macOS we suppress the deployment target warning: an old Conan profile may not pin os.version.
+# Only the new Apple linker understands the flag, so probe the actual linker (lld may be selected above).
+if(is_macos OR is_linux)
+    if(is_ci OR is_nix_compiler)
+        if(is_macos)
+            set(fatal_warnings_flag "-Wl,-fatal_warnings")
+        else()
+            set(fatal_warnings_flag "-Wl,--fatal-warnings")
+        endif()
+        message(
+            STATUS
+            "Treating all linker warnings as errors (${fatal_warnings_flag})"
+        )
+        target_link_options(common INTERFACE "${fatal_warnings_flag}")
+        unset(fatal_warnings_flag)
+    elseif(is_macos)
+        set(silence_flag "-Wl,-deployment_target_mismatches,suppress")
+        set(probe_flags ${fuse_ld_flag} "${silence_flag}")
+        include(CheckLinkerFlag)
+        check_linker_flag(
+            CXX
+            "${probe_flags}"
+            have_deployment_target_mismatches
+        )
+        if(have_deployment_target_mismatches)
+            message(
+                STATUS
+                "Silencing macOS deployment target mismatch warnings (${silence_flag})"
+            )
+            target_link_options(common INTERFACE "${silence_flag}")
+        endif()
+        unset(probe_flags)
+        unset(silence_flag)
+    endif()
+endif()
+unset(fuse_ld_flag)
+
 if(assert)
     foreach(var_ CMAKE_C_FLAGS_RELEASE CMAKE_CXX_FLAGS_RELEASE)
         string(REGEX REPLACE "[-/]DNDEBUG" "" ${var_} "${${var_}}")

cmake/XrplCore.cmake

@@ -51,6 +51,8 @@ target_compile_options(
 
 target_link_libraries(xrpl.libpb PUBLIC protobuf::libprotobuf gRPC::grpc++)
 
+add_dependencies(tidy_prerequisites xrpl.libpb)
+
 # TODO: Clean up the number of library targets later.
 add_library(xrpl.imports.main INTERFACE)
 
@@ -94,6 +96,9 @@ add_module(xrpl basics)
 target_link_libraries(xrpl.libxrpl.basics PUBLIC xrpl.libxrpl.beast)
 
 # Level 03
+add_module(xrpl config)
+target_link_libraries(xrpl.libxrpl.config PUBLIC xrpl.libxrpl.basics)
+
 add_module(xrpl json)
 target_link_libraries(xrpl.libxrpl.json PUBLIC xrpl.libxrpl.basics)
 
@@ -120,6 +125,7 @@ target_link_libraries(
     xrpl.libxrpl.core
     PUBLIC
         xrpl.libxrpl.basics
+        xrpl.libxrpl.config
         xrpl.libxrpl.json
         xrpl.libxrpl.protocol
         xrpl.libxrpl.protocol_autogen
@@ -129,6 +135,12 @@ target_link_libraries(
 add_module(xrpl resource)
 target_link_libraries(xrpl.libxrpl.resource PUBLIC xrpl.libxrpl.protocol)
 
+add_module(xrpl peerfinder)
+target_link_libraries(
+    xrpl.libxrpl.peerfinder
+    PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.protocol
+)
+
 # Level 08
 add_module(xrpl net)
 target_link_libraries(
@@ -143,7 +155,11 @@ target_link_libraries(
 add_module(xrpl nodestore)
 target_link_libraries(
     xrpl.libxrpl.nodestore
-    PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.json xrpl.libxrpl.protocol
+    PUBLIC
+        xrpl.libxrpl.basics
+        xrpl.libxrpl.config
+        xrpl.libxrpl.json
+        xrpl.libxrpl.protocol
 )
 
 add_module(xrpl shamap)
@@ -159,13 +175,14 @@ target_link_libraries(
 add_module(xrpl rdb)
 target_link_libraries(
     xrpl.libxrpl.rdb
-    PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.core
+    PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.config xrpl.libxrpl.core
 )
 
 add_module(xrpl server)
 target_link_libraries(
     xrpl.libxrpl.server
     PUBLIC
+        xrpl.libxrpl.config
         xrpl.libxrpl.protocol
         xrpl.libxrpl.core
         xrpl.libxrpl.rdb
@@ -192,6 +209,16 @@ target_link_libraries(
 add_module(xrpl tx)
 target_link_libraries(xrpl.libxrpl.tx PUBLIC xrpl.libxrpl.ledger)
 
+add_module(xrpl consensus)
+target_link_libraries(
+    xrpl.libxrpl.consensus
+    PUBLIC
+        xrpl.libxrpl.basics
+        xrpl.libxrpl.json
+        xrpl.libxrpl.protocol
+        xrpl.libxrpl.ledger
+)
+
 add_library(xrpl.libxrpl)
 set_target_properties(xrpl.libxrpl PROPERTIES OUTPUT_NAME xrpl)
 
@@ -210,6 +237,8 @@ target_link_modules(
     basics
     beast
     conditions
+    config
+    consensus
     core
     crypto
     git
@@ -217,6 +246,7 @@ target_link_modules(
     ledger
     net
     nodestore
+    peerfinder
     protocol
     protocol_autogen
     rdb
@@ -237,6 +267,7 @@ target_link_modules(
 
 if(xrpld)
     add_executable(xrpld)
+    patch_nix_binary(xrpld)
     if(tests)
         target_compile_definitions(xrpld PUBLIC ENABLE_TESTS)
         target_compile_definitions(
@@ -282,4 +313,13 @@ if(xrpld)
             PRIVATE ${CMAKE_SOURCE_DIR}/external/antithesis-sdk
         )
     endif()
+
+    # The xrpld headers are not built with add_module, so verify them against
+    # the executable's own compile environment.
+    if(verify_headers)
+        verify_target_headers(xrpld "${CMAKE_CURRENT_SOURCE_DIR}/src/xrpld")
+        if(tests)
+            verify_target_headers(xrpld "${CMAKE_CURRENT_SOURCE_DIR}/src/test")
+        endif()
+    endif()
 endif()

cmake/XrplCov.cmake

@@ -44,10 +44,11 @@ setup_target_for_coverage_gcovr(
     EXCLUDE
         "src/test"
         "src/tests"
+        "src/benchmarks"
         "include/xrpl/beast/test"
         "include/xrpl/beast/unit_test"
         "${CMAKE_BINARY_DIR}/pb-xrpl.libpb"
-    DEPENDENCIES xrpld xrpl.tests
+    DEPENDENCIES xrpld xrpl_tests
 )
 
 add_code_coverage_to_target(opts INTERFACE)

cmake/XrplPackaging.cmake

@@ -25,10 +25,22 @@ if(NOT (RPMBUILD_EXECUTABLE OR DPKG_BUILDPACKAGE_EXECUTABLE))
     return()
 endif()
 
+if(NOT TARGET xrpld)
+    message(STATUS "xrpld=ON is required; 'package' target not available")
+    return()
+endif()
+
+if(NOT TARGET validator-keys)
+    message(
+        STATUS
+        "validator_keys=ON is required; 'package' target not available"
+    )
+    return()
+endif()
+
 set(package_env
     SRC_DIR=${CMAKE_SOURCE_DIR}
     BUILD_DIR=${CMAKE_BINARY_DIR}
-    PKG_VERSION=${xrpld_version}
     PKG_RELEASE=${pkg_release}
 )
 
@@ -38,7 +50,7 @@ add_custom_target(
         ${CMAKE_COMMAND} -E env ${package_env}
         ${CMAKE_SOURCE_DIR}/package/build_pkg.sh
     WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
-    DEPENDS xrpld
+    DEPENDS xrpld validator-keys
     COMMENT "Building Linux package (deb/rpm inferred from host tooling)"
     VERBATIM
 )

cmake/XrplProtocolAutogen.cmake

@@ -2,21 +2,22 @@
    Protocol Autogen - Code generation for protocol wrapper classes
 #]===================================================================]
 
+# The repository root, derived from the location of this file rather than from
+# the including project, so that the targets below can also be offered on their
+# own by cmake/codegen/CMakeLists.txt.
+get_filename_component(XRPL_ROOT "${CMAKE_CURRENT_LIST_DIR}/.." ABSOLUTE)
+
 set(CODEGEN_VENV_DIR
-    "${CMAKE_CURRENT_SOURCE_DIR}/.venv"
+    "${XRPL_ROOT}/.venv"
     CACHE PATH
     "Path to a Python virtual environment for code generation. A venv will be created here by setup_code_gen and used to run generation scripts."
 )
 
 # Directory paths
-set(MACRO_DIR "${CMAKE_CURRENT_SOURCE_DIR}/include/xrpl/protocol/detail")
-set(AUTOGEN_HEADER_DIR
-    "${CMAKE_CURRENT_SOURCE_DIR}/include/xrpl/protocol_autogen"
-)
-set(AUTOGEN_TEST_DIR
-    "${CMAKE_CURRENT_SOURCE_DIR}/src/tests/libxrpl/protocol_autogen"
-)
-set(SCRIPTS_DIR "${CMAKE_CURRENT_SOURCE_DIR}/cmake/scripts/codegen")
+set(MACRO_DIR "${XRPL_ROOT}/include/xrpl/protocol/detail")
+set(AUTOGEN_HEADER_DIR "${XRPL_ROOT}/include/xrpl/protocol_autogen")
+set(AUTOGEN_TEST_DIR "${XRPL_ROOT}/src/tests/libxrpl/protocol_autogen")
+set(SCRIPTS_DIR "${XRPL_ROOT}/cmake/scripts/codegen")
 
 # Input macro files
 set(TRANSACTIONS_MACRO "${MACRO_DIR}/transactions.macro")
@@ -114,14 +115,14 @@ if(CODEGEN_VENV_DIR)
         setup_code_gen
         COMMAND ${Python3_EXECUTABLE} -m venv "${CODEGEN_VENV_DIR}"
         COMMAND ${CODEGEN_PYTHON} -m pip install -r "${REQUIREMENTS_FILE}"
-        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        WORKING_DIRECTORY "${XRPL_ROOT}"
         COMMENT "Creating venv and installing code generation dependencies..."
     )
 else()
     add_custom_target(
         setup_code_gen
         COMMAND ${Python3_EXECUTABLE} -m pip install -r "${REQUIREMENTS_FILE}"
-        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        WORKING_DIRECTORY "${XRPL_ROOT}"
         COMMENT "Installing code generation dependencies..."
     )
 endif()
@@ -139,8 +140,8 @@ add_custom_target(
         -DSFIELDS_MACRO=${SFIELDS_MACRO}
         -DAUTOGEN_HEADER_DIR=${AUTOGEN_HEADER_DIR}
         -DAUTOGEN_TEST_DIR=${AUTOGEN_TEST_DIR} -P
-        "${CMAKE_CURRENT_SOURCE_DIR}/cmake/XrplProtocolAutogenRun.cmake"
-    WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        "${CMAKE_CURRENT_LIST_DIR}/XrplProtocolAutogenRun.cmake"
+    WORKING_DIRECTORY "${XRPL_ROOT}"
     COMMENT "Running protocol code generation..."
     SOURCES ${ALL_INPUT_FILES}
 )

cmake/XrplSanitizers.cmake

@@ -14,11 +14,9 @@
 include_guard(GLOBAL)
 include(CompilationEnv)
 
-if(NOT DEFINED SANITIZERS)
-    set(SANITIZERS_ENABLED FALSE)
+if(NOT SANITIZERS_ENABLED)
     return()
 endif()
-set(SANITIZERS_ENABLED TRUE)
 
 message(STATUS "=== Configuring Sanitizers ===")
 message(STATUS "  SANITIZERS: ${SANITIZERS}")

cmake/XrplSanity.cmake

@@ -36,6 +36,19 @@ elseif(is_gcc)
     endif()
 endif()
 
+# A Nix compiler is only meant to be used from a managed environment: the xrpld
+# dev shell (which exports XRPL_DEVSHELL) or the CI image. Using one from a bare
+# shell usually means a leaked toolchain (picked up via PATH or a Conan profile)
+# and leads to confusing breakage, so fail early with guidance.
+if(is_nix_compiler AND NOT is_ci_image AND NOT DEFINED ENV{XRPL_DEVSHELL})
+    message(
+        FATAL_ERROR
+        "A Nix compiler (${CMAKE_CXX_COMPILER}) is being used outside the xrpld "
+        "dev shell. Enter it with `nix develop` (see docs/build/nix.md) before "
+        "configuring the build."
+    )
+endif()
+
 # check for in-source build and fail
 if("${CMAKE_CURRENT_SOURCE_DIR}" STREQUAL "${CMAKE_BINARY_DIR}")
     message(

cmake/XrplSettings.cmake

@@ -30,6 +30,30 @@ if(tests)
     endif()
 endif()
 
+option(benchmark "Build benchmarks" ON)
+
+# When OFF, the crates directory is not added to the build at all: no Rust
+# toolchain is required, no cxxbridge bindings are generated, and the C++ tests
+# that consume those bindings are left out of the build tree.
+option(rust "Build the Rust crates and the C++ code that depends on them" OFF)
+
+# Enabled by default so every header is compiled on its own as the main file of
+# its own compile_commands.json entry - this is what lets clang-tidy (and clangd
+# and IDEs) analyse a header's own includes directly. The per-header objects are
+# EXCLUDE_FROM_ALL (see cmake/verify_headers.cmake) and the aggregate target
+# below is not part of `all`, so a normal `cmake --build` never compiles them.
+option(
+    verify_headers
+    "Compile every header on its own to verify it is self-contained."
+    ON
+)
+if(verify_headers)
+    # Aggregate target that builds every per-module header-verification library
+    # created by add_module (see cmake/verify_headers.cmake). Build it with:
+    #   cmake --build . --target verify-headers
+    add_custom_target(verify-headers)
+endif()
+
 option(unity "Creates a build using UNITY support in cmake." OFF)
 if(unity)
     if(NOT is_ci)

cmake/XrplValidatorKeys.cmake

@@ -5,22 +5,39 @@ option(
 )
 
 if(validator_keys)
-    git_branch(current_branch)
-    # default to tracking VK master branch unless we are on release
-    if(NOT (current_branch STREQUAL "release"))
-        set(current_branch "master")
-    endif()
-    message(STATUS "Tracking ValidatorKeys branch: ${current_branch}")
+    # Own the install destination below rather than relying on another module
+    # having pulled this in first.
+    include(GNUInstallDirs)
+
+    # Pinned to an exact commit, not a branch: the tool ships inside our
+    # packages, so the same xrpld version must always package the same
+    # validator-keys. Bump this deliberately.
+    set(validator_keys_commit "4c0fb75eec9601c711645998c904507e87e910ae")
+    message(STATUS "Using ValidatorKeys commit: ${validator_keys_commit}")
 
     FetchContent_Declare(
         validator_keys
         GIT_REPOSITORY https://github.com/ripple/validator-keys-tool.git
-        GIT_TAG "${current_branch}"
+        GIT_TAG "${validator_keys_commit}"
     )
     FetchContent_MakeAvailable(validator_keys)
+    # The tool's own CMakeLists excludes the target from 'all' when it is built
+    # as a subproject. Undo that, so validator_keys=ON really does build it.
     set_target_properties(
         validator-keys
-        PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}"
+        PROPERTIES
+            RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}"
+            EXCLUDE_FROM_ALL OFF
+            EXCLUDE_FROM_DEFAULT_BUILD OFF
+    )
+    # We ship this binary, so like xrpld it must not keep the Nix store's ELF
+    # loader, or it cannot run on the target distro at all.
+    patch_nix_binary(validator-keys)
+
+    configure_file(
+        "${validator_keys_SOURCE_DIR}/LICENSE"
+        "${CMAKE_BINARY_DIR}/validator-keys-LICENSE"
+        COPYONLY
     )
     install(TARGETS validator-keys RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 endif()

cmake/add_module.cmake

@@ -1,4 +1,5 @@
 include(isolate_headers)
+include(verify_headers)
 
 # Create an OBJECT library target named
 #
@@ -37,4 +38,20 @@ function(add_module parent name)
         "${CMAKE_CURRENT_SOURCE_DIR}/src/lib${parent}/${name}"
         PRIVATE
     )
+    # protocol_autogen contains generated headers that are deliberately exempt
+    # from clang-tidy (see ExcludeHeaderFilterRegex in .clang-tidy), so we do not
+    # verify them either.
+    if(
+        verify_headers
+        AND NOT "${parent}/${name}" STREQUAL "xrpl/protocol_autogen"
+    )
+        verify_target_headers(
+            ${target}
+            "${CMAKE_CURRENT_SOURCE_DIR}/include/${parent}/${name}"
+        )
+        verify_target_headers(
+            ${target}
+            "${CMAKE_CURRENT_SOURCE_DIR}/src/lib${parent}/${name}"
+        )
+    endif()
 endfunction()

cmake/codegen/CMakeLists.txt

@@ -0,0 +1,21 @@
+#[===================================================================[
+   Protocol Autogen - Standalone project
+
+   Exposes the 'setup_code_gen' and 'code_gen' targets on their own, without
+   configuring the rest of xrpl. Code generation is pure Python, so this needs
+   neither the dependencies nor a compiler, which makes it usable in CI and by
+   contributors who only want to regenerate the protocol wrapper classes:
+
+     cmake -S cmake/codegen -B build/codegen
+     cmake --build build/codegen --target setup_code_gen
+     cmake --build build/codegen --target code_gen
+
+   The targets are identical to the ones offered by the top-level build, since
+   both come from cmake/XrplProtocolAutogen.cmake.
+#]===================================================================]
+
+cmake_minimum_required(VERSION 3.16)
+
+project(xrpl_codegen LANGUAGES NONE)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../XrplProtocolAutogen.cmake")

cmake/scripts/codegen/templates/LedgerEntry.h.mako

@@ -33,7 +33,7 @@ public:
      * @brief Construct a ${name} ledger entry wrapper from an existing SLE object.
      * @throws std::runtime_error if the ledger entry type doesn't match.
      */
-    explicit ${name}(std::shared_ptr<SLE const> sle)
+    explicit ${name}(SLE::const_pointer sle)
         : LedgerEntryBase(std::move(sle))
     {
         // Verify ledger entry type
@@ -168,7 +168,7 @@ ${field['typeData']['setter_type']} ${field['paramName']}${',' if i < len(requir
      * @param sle The existing ledger entry to copy from.
      * @throws std::runtime_error if the ledger entry type doesn't match.
      */
-    ${name}Builder(std::shared_ptr<SLE const> sle)
+    ${name}Builder(SLE::const_pointer sle)
     {
         if (sle->at(sfLedgerEntryType) != ${tag})
         {
@@ -177,7 +177,9 @@ ${field['typeData']['setter_type']} ${field['paramName']}${',' if i < len(requir
         object_ = *sle;
     }
 
-    /** @brief Ledger entry-specific field setters */
+    /**
+     * @brief Ledger entry-specific field setters
+     */
 % for field in fields:
 
     /**

cmake/scripts/codegen/templates/Transaction.h.mako

@@ -185,7 +185,9 @@ public:
         object_ = *tx;
     }
 
-    /** @brief Transaction-specific field setters */
+    /**
+     * @brief Transaction-specific field setters
+     */
 % for field in fields:
 
     /**

cmake/verify_headers.cmake

@@ -0,0 +1,84 @@
+# Our normal build only ever compiles `.cpp` files, so a header is only ever
+# checked through whatever translation unit happens to include it. A header that
+# is missing an `#include` is never caught as long as every `.cpp` that uses it
+# includes its missing dependency first. To check a header on its own we compile
+# it directly as a translation unit.
+#
+# Compiling the header itself - rather than a `.cpp` wrapper that includes it -
+# gives two checks at once:
+#   * the compiler fails if the header is not self-contained, i.e. it uses a
+#     declaration that is not available (directly or transitively); and
+#   * the header is the *main file* of its `compile_commands.json` entry, so
+#     clang-tidy's misc-include-cleaner analyses (and can --fix) the header's own
+#     includes - flagging a dependency that is only available transitively, which
+#     a plain compile cannot catch. A wrapper would be the main file instead, and
+#     include-cleaner never looks inside the headers a main file includes.
+#
+# The objects are never linked anywhere; we build them only for these checks.
+
+# Verify that the headers under headers_dir compile on their own, using the
+# compile environment of an existing target so each header is compiled exactly as
+# that target compiles it. This works for both add_module libraries and the xrpld
+# and test binaries: a library's isolated public and private include directories
+# and a binary's `-I src` both live in its INCLUDE_DIRECTORIES, and the modules or
+# libraries it links live in its LINK_LIBRARIES. We copy those usage requirements
+# through generator expressions (rather than linking ${target}, which is
+# impossible for an executable), evaluated at generation time so they capture
+# requirements the caller adds after this runs. The verify library is created
+# once; call this repeatedly to add more header directories.
+#
+# verify_target_headers(target headers_dir)
+function(verify_target_headers target headers_dir)
+    set(verify ${target}.verify)
+    if(NOT TARGET ${verify})
+        add_library(${verify} OBJECT EXCLUDE_FROM_ALL)
+        # A unity build would concatenate the headers into a single translation
+        # unit, where a header missing an include could be satisfied by one that
+        # precedes it in the blob - exactly the bug we want to catch.
+        set_target_properties(${verify} PROPERTIES UNITY_BUILD OFF)
+        target_include_directories(
+            ${verify}
+            PRIVATE $<TARGET_PROPERTY:${target},INCLUDE_DIRECTORIES>
+        )
+        target_compile_definitions(
+            ${verify}
+            PRIVATE $<TARGET_PROPERTY:${target},COMPILE_DEFINITIONS>
+        )
+        target_compile_options(
+            ${verify}
+            PRIVATE $<TARGET_PROPERTY:${target},COMPILE_OPTIONS>
+        )
+        target_link_libraries(
+            ${verify}
+            PRIVATE $<TARGET_PROPERTY:${target},LINK_LIBRARIES>
+        )
+        add_dependencies(verify-headers ${verify})
+    endif()
+    _verify_add_headers(${verify} "${headers_dir}")
+endfunction()
+
+# Add every .h/.hpp under dir to target as a directly-compiled C++ translation
+# unit. .ipp files are inline-implementation fragments included by their owning
+# header (often after a class declaration), so they are not self-contained on
+# their own and are verified transitively when that header is verified.
+function(_verify_add_headers target dir)
+    file(GLOB_RECURSE headers CONFIGURE_DEPENDS "${dir}/*.h" "${dir}/*.hpp")
+    if(NOT headers)
+        return()
+    endif()
+    # `-xc++` forces the header to be compiled as a C++ translation unit; a lone
+    # `.h` is otherwise treated as a header to precompile. `#pragma once` is
+    # harmless (and warns) when the header is the main file, so silence it.
+    # Compiled on its own, a header legitimately defines constants and static or
+    # template functions that nothing in this single translation unit uses (they
+    # exist for the files that include it), so the resulting unused-entity
+    # warnings are expected and must not fail the build under -Werror.
+    set_source_files_properties(
+        ${headers}
+        PROPERTIES
+            LANGUAGE CXX
+            COMPILE_OPTIONS
+                "-xc++;-Wno-pragma-once-outside-header;-Wno-unused-const-variable;-Wno-unused-function"
+    )
+    target_sources(${target} PRIVATE ${headers})
+endfunction()

conan.lock

@@ -1,43 +1,47 @@
 {
     "version": "0.5",
     "requires": [
-        "zlib/1.3.2#1cb806da49011867778ffb6ac7190fcb%1777558780.503",
-        "xxhash/0.8.3#681d36a0a6111fc56e5e45ea182c19cc%1765850149.987",
-        "sqlite3/3.53.0#324ada52333108388a9a6108bfa96734%1776096494.149",
-        "soci/4.0.3#fe32b9ad5eb47e79ab9e45a68f363945%1774450067.231",
-        "snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1765850147.878",
-        "secp256k1/0.7.1#481881709eb0bdd0185a12b912bbe8ad%1770910500.329",
-        "rocksdb/10.5.1#4a197eca381a3e5ae8adf8cffa5aacd0%1765850186.86",
-        "re2/20251105#8579cfd0bda4daf0683f9e3898f964b4%1774398111.888",
-        "protobuf/6.33.5#d96d52ba5baaaa532f47bda866ad87a5%1774467363.12",
-        "openssl/3.6.2#4789bbf131b77d0515d15e094c8f697f%1778071755.506",
-        "nudb/2.0.9#11149c73f8f2baff9a0198fe25971fc7%1775040983.408",
-        "lz4/1.10.0#59fc63cac7f10fbe8e05c7e62c2f3504%1765850143.914",
-        "libiconv/1.17#1e65319e945f2d31941a9d28cc13c058%1765842973.492",
-        "libbacktrace/cci.20210118#a7691bfccd8caaf66309df196790a5a1%1765842973.03",
-        "libarchive/3.8.7#c446109bd1f1d8ba7936c94189bc50e6%1776147552.838",
+        "zlib/1.3.2#1cb806da49011867778ffb6ac7190fcb%1782392402.122708",
+        "xxhash/0.8.3#681d36a0a6111fc56e5e45ea182c19cc%1782392402.420688",
+        "sqlite3/3.53.0#324ada52333108388a9a6108bfa96734%1782392403.185447",
+        "soci/4.0.3#e726491a03468795453f7c83fc924a96%1782392402.679521",
+        "snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1782307151.633168",
+        "secp256k1/0.7.1#b1f450b7f78a36fff75bb6934a356f3a%1782338841.3729",
+        "rocksdb/10.5.1#4a197eca381a3e5ae8adf8cffa5aacd0%1782392413.075713",
+        "re2/20251105#8579cfd0bda4daf0683f9e3898f964b4%1782392402.431897",
+        "protobuf/6.33.5#ff253ead763bd8d9904a52979cd21e81%1782392410.233933",
+        "openssl/3.6.3#f806de8933e3bf6f01016c6a888cee2e%1783945160.863288",
+        "nudb/2.0.9#11149c73f8f2baff9a0198fe25971fc7%1782392402.297166",
+        "mpt-crypto/1.0.2#b313cef0c1a493eb970ad185b2e9bab7%1784285108.866483",
+        "lz4/1.10.0#982d9b673900f665a1da109e09c17cab%1782392402.164188",
+        "libiconv/1.17#9923bc6dc6f106646d6967e0039a5ada%1782392792.775744",
+        "libbacktrace/cci.20210118#a7691bfccd8caaf66309df196790a5a1%1782392402.420732",
+        "libarchive/3.8.7#c446109bd1f1d8ba7936c94189bc50e6%1782392403.066892",
         "jemalloc/5.3.1#1fc58d55316041f10fbc1e8a2eae632a%1776700028.228",
-        "gtest/1.17.0#5224b3b3ff3b4ce1133cbdd27d53ee7d%1768312129.152",
-        "grpc/1.78.1#b1a9e74b145cc471bed4dc64dc6eb2c1%1774467387.342",
-        "ed25519/2015.03#ae761bdc52730a843f0809bdf6c1b1f6%1765850143.772",
-        "date/3.0.4#862e11e80030356b53c2c38599ceb32b%1765850143.772",
-        "c-ares/1.34.6#545240bb1c40e2cacd4362d6b8967650%1774439234.681",
-        "bzip2/1.0.8#c470882369c2d95c5c77e970c0c7e321%1765850143.837",
-        "boost/1.91.0#ea540ca2133d831b560036aa24dece3c%1778050991.9",
-        "abseil/20250127.0#bb0baf1f362bc4a725a24eddd419b8f7%1774365460.196"
+        "gtest/1.17.0#5224b3b3ff3b4ce1133cbdd27d53ee7d%1782392402.791979",
+        "grpc/1.81.1#f729f6d75992d20f9c72828e9142d62f%1783945160.094135",
+        "fast_float/8.2.10#f6f28d6bb22112078e7dbda611caf681%1782494504.298",
+        "ed25519/2015.03#ae761bdc52730a843f0809bdf6c1b1f6%1782307148.15562",
+        "date/3.0.4#862e11e80030356b53c2c38599ceb32b%1782392402.538492",
+        "corrosion/0.6.1#bfa292df0a957bc70a450ff316cd9435%1786119416.131296",
+        "c-ares/1.34.6#545240bb1c40e2cacd4362d6b8967650%1782392402.681654",
+        "bzip2/1.0.8#c470882369c2d95c5c77e970c0c7e321%1782392402.296732",
+        "boost/1.91.0#ea540ca2133d831b560036aa24dece3c%1782392419.475605",
+        "benchmark/1.9.5#b885dc73ad67b40a55d45684d1c88ad1%1782736613.864841",
+        "abseil/20250127.0#9ef01c1451a8340f9022e46238c0fbb6%1783945159.651047"
     ],
     "build_requires": [
-        "zlib/1.3.2#1cb806da49011867778ffb6ac7190fcb%1777558780.503",
-        "strawberryperl/5.32.1.1#8d114504d172cfea8ea1662d09b6333e%1774447376.964",
-        "protobuf/6.33.5#d96d52ba5baaaa532f47bda866ad87a5%1774467363.12",
-        "nasm/2.16.01#31e26f2ee3c4346ecd347911bd126904%1765850144.707",
+        "zlib/1.3.2#1cb806da49011867778ffb6ac7190fcb%1782392402.122708",
+        "strawberryperl/5.32.1.1#8d114504d172cfea8ea1662d09b6333e%1782395692.540639",
+        "protobuf/6.33.5#ff253ead763bd8d9904a52979cd21e81%1782392410.233933",
+        "nasm/2.16.01#31e26f2ee3c4346ecd347911bd126904%1782395690.33162",
         "msys2/cci.latest#d22fe7b2808f5fd34d0a7923ace9c54f%1770657326.649",
-        "m4/1.4.19#4523e4347b55cd26ae918bd5770cab9a%1778062762.471",
-        "cmake/4.3.0#b939a42e98f593fb34d3a8c5cc860359%1774439249.183",
-        "b2/5.4.2#ffd6084a119587e70f11cd45d1a386e2%1774439233.447",
+        "m4/1.4.19#1727f439cf74e83826ec96d0b4904eee%1784541921.659",
+        "cmake/4.3.3#840cf00ea09777e05c2050a50a82c722%1782392418.696091",
+        "b2/5.4.2#ffd6084a119587e70f11cd45d1a386e2%1782392402.624226",
         "automake/1.16.5#b91b7c384c3deaa9d535be02da14d04f%1755524470.56",
         "autoconf/2.71#51077f068e61700d65bb05541ea1e4b0%1731054366.86",
-        "abseil/20250127.0#bb0baf1f362bc4a725a24eddd419b8f7%1774365460.196"
+        "abseil/20250127.0#9ef01c1451a8340f9022e46238c0fbb6%1783945159.651047"
     ],
     "python_requires": [],
     "overrides": {
@@ -57,7 +61,7 @@
             "boost/1.91.0"
         ],
         "lz4/[>=1.9.4 <2]": [
-            "lz4/1.10.0#59fc63cac7f10fbe8e05c7e62c2f3504"
+            "lz4/1.10.0#982d9b673900f665a1da109e09c17cab"
         ]
     },
     "config_requires": []

conan/init.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Install our Conan configuration, profiles and the xrplf remote into CONAN_HOME.
+# Safe to re-run; never deletes the Conan home.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
+CONAN_DIR="$(conan config home)"
+
+echo "Installing Conan configuration into ${CONAN_DIR}"
+conan config install "${SCRIPT_DIR}/global.conf"
+conan config install "${SCRIPT_DIR}/profiles" -tf "${CONAN_DIR}/profiles"
+# This script manages these files, so make them read-only - Conan does not
+# preserve the source mode. Only the files: the directories must stay writable
+# for `conan config install` to replace them.
+chmod a-w "${CONAN_DIR}/global.conf"
+find "${CONAN_DIR}/profiles" -type f -exec chmod a-w {} +
+
+echo "Adding the xrplf Conan remote"
+# --index 0: our patched recipes must win over Conan Center.
+conan remote add --index 0 --force xrplf https://conan.xrplf.org/repository/conan/

conan/lockfile/linux.profile

@@ -2,7 +2,7 @@
 arch=x86_64
 build_type=Release
 compiler=gcc
-compiler.cppstd=20
+compiler.cppstd=23
 compiler.libcxx=libstdc++11
 compiler.version=13
 os=Linux

conan/lockfile/macos.profile

@@ -2,7 +2,7 @@
 arch=armv8
 build_type=Release
 compiler=apple-clang
-compiler.cppstd=20
+compiler.cppstd=23
 compiler.libcxx=libc++
 compiler.version=17.0
 os=Macos