Merge branch 'develop' into copilot/add-augmented-submit-fields

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: mvadari <8029314+mvadari@users.noreply.github.com>
Co-authored-by: Mayukha Vadari <mvadari@ripple.com>
Co-authored-by: Ayaz Salikhov <mathbunnyru@users.noreply.github.com>
Co-authored-by: xrplf-ai-reviewer[bot] <266832837+xrplf-ai-reviewer[bot]@users.noreply.github.com>
Co-authored-by: Mayukha Vadari <mvadari@gmail.com>
Co-authored-by: Timur Yalymov <36795566+tyalymov@users.noreply.github.com>
Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: Vito Tumas <5780819+Tapanito@users.noreply.github.com>

.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
@@ -365,6 +366,7 @@ words:
   - xchain
   - ximinez
   - XMACRO
+  - xored
   - xrpkuwait
   - xrpl
   - xrpld

.envrc

@@ -1,3 +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

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

@@ -1,5 +1,5 @@
 {
-  "image_tag": "sha-fecfc0c",
+  "image_tag": "sha-a0074f8",
   "configs": {
     "ubuntu": [
       {

.github/workflows/publish-docs.yml

@@ -41,7 +41,7 @@ env:
 jobs:
   build:
     runs-on: ubuntu-latest
-    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-fecfc0c
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
     steps:
       - name: Checkout repository
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1

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

@@ -34,7 +34,7 @@ jobs:
     needs: [determine-files]
     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/xrpld/nix-debian:sha-fecfc0c"
+    container: "ghcr.io/xrplf/xrpld/nix-debian:sha-a0074f8"
     permissions:
       contents: read
       issues: write

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

@@ -40,7 +40,7 @@ defaults:
 jobs:
   upload:
     runs-on: ubuntu-latest
-    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-fecfc0c
+    container: ghcr.io/xrplf/xrpld/nix-ubuntu:sha-a0074f8
     env:
       REMOTE_NAME: ${{ inputs.remote_name }}
       CONAN_LOGIN_USERNAME_XRPLF: ${{ secrets.remote_username }}

API-CHANGELOG.md

@@ -39,6 +39,7 @@ This section contains changes targeting a future version.
   - `TRANSACTION_FLAGS`: Maps transaction type names to their supported flags and flag values.
   - `LEDGER_ENTRY_FLAGS`: Maps ledger entry type names to their flags and flag values.
   - `ACCOUNT_SET_FLAGS`: Maps AccountSet flag names (asf flags) to their numeric values.
+- `submit`: Augmented response fields (`accepted`, `applied`, `broadcast`, `queued`, `kept`, `account_sequence_next`, `account_sequence_available`, `open_ledger_cost`, `validated_ledger_index`) are now included in sign-and-submit mode. Previously, these fields were only returned when submitting a binary transaction blob.
 
 ### Bugfixes
 
@@ -54,6 +55,8 @@ 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

@@ -4,34 +4,14 @@
 
 ## Minimum Requirements
 
-See [System Requirements](https://xrpl.org/system-requirements.html).
+For the hardware needed to run a node, see
+[System Requirements](https://xrpl.org/system-requirements.html).
 
-Building xrpld generally requires Git, Python, Conan, CMake, and a C++
-compiler.
-
-- [Python](https://www.python.org/downloads/)
-- [Conan](https://conan.io/downloads.html)
-- [CMake](https://cmake.org/download/)
-
-You can verify that the required tools are installed and runnable with:
-
-```bash
-./bin/check-tools.sh
-```
-
-`xrpld` is written in the C++23 dialect. The [tested compiler versions][cpp23-support] are:
-
-| Compiler    | Version         |
-| ----------- | --------------- |
-| GCC         | 15.2            |
-| Clang       | 22              |
-| Apple Clang | 21              |
-| MSVC        | 19.44[^windows] |
+For the software needed to build xrpld, see the
+[environment setup guide](./docs/build/environment.md).
 
 ## Operating Systems
 
-Please see the [environment setup guide](./docs/build/environment.md) for detailed instructions for all platforms.
-
 ### Linux
 
 The Ubuntu Linux distribution has received the highest level of quality
@@ -47,9 +27,8 @@ CI testing is done in macOS 26 (Tahoe), but the build defaults `CMAKE_OSX_DEPLOY
 
 ### Windows
 
-Windows is used by some engineers for development only.
-
-[^windows]: Windows is not recommended for production use.
+Windows is used by some engineers for development only, and is not recommended
+for production use.
 
 ## Steps
 
@@ -74,37 +53,25 @@ 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][conan-getting-started] walkthrough.
-
-#### Profiles
-
-We recommend that you install our Conan profiles:
+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.
 
-If the default profile is not suitable for your environment, you can create a custom profile and pass it to Conan.
-More information on customizing Conan can be found in the [Advanced Conan configuration](./docs/build/advanced_conan.md).
-
-#### Add xrplf remote
-
-Run the following command to add the `xrplf` remote, which hosts some of our dependencies:
-
-```bash
-conan remote add --index 0 --force xrplf https://conan.xrplf.org/repository/conan/
-```
+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
 
@@ -269,10 +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`
@@ -389,10 +360,14 @@ After any updates or changes to dependencies, you may need to do the following:
 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](#add-xrplf-remote) or re-run `conan export` for [patched recipes](./docs/build/advanced_conan.md#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
 
@@ -412,7 +387,6 @@ 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`
 
-[cpp23-support]: https://en.cppreference.com/w/cpp/compiler_support/23
 [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

bin/check-tools.sh

@@ -15,10 +15,14 @@
 #   - 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, 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.
+# 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.
@@ -26,14 +30,27 @@
 
 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 one aligned line: the status, the name, and the first
-# non-blank line of the probe output (its version). Records <name> as missing
-# if the command is not found or exits non-zero.
+# 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
@@ -43,14 +60,17 @@ check() {
     fi
 
     checked=$((checked + 1))
-    local output version
+    local output version path
+    path="$(tool_path "${name}")"
     if output="$("${probe[@]}" 2>&1)"; then
-        version="$(printf '%s\n' "${output}" | grep -m1 '[^[:space:]]' || true)"
-        printf '  [ ok ] %-20s %s\n' "${name}" "${version}"
+        printf '  ✅ %s\n' "${name}"
     else
-        printf '  [MISS] %s\n' "${name}"
+        printf '  ❌ %s\n' "${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 "$(uname -s)" in
@@ -82,7 +102,9 @@ if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
     echo "Development tooling:"
     check ccache
     check clang
+    check "clang-${llvm_version}"
     check clang++
+    check "clang++-${llvm_version}"
     check ClangBuildAnalyzer
     check curl
     check file
@@ -101,7 +123,14 @@ if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
     # setups, but not in the macOS CI environment. So check them everywhere
     # except when running in CI on macOS.
     if [ "${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} ${tidy_probe}"
         check dot
         check doxygen
         check gcovr
@@ -112,6 +141,7 @@ if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
         # pre-commit, or its alternative implementation prek
         check pre-commit sh -c 'pre-commit --version || prek --version'
         check run-clang-tidy run-clang-tidy --help
+        check "run-clang-tidy-${llvm_version}" "run-clang-tidy-${llvm_version}" --help
     fi
 fi
 
@@ -126,7 +156,7 @@ if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
     check cargo-audit cargo audit --version
     check cargo-llvm-cov cargo llvm-cov --version
     check cargo-nextest cargo nextest --version
-    check clippy clippy-driver --version
+    check clippy-driver
     check rust-analyzer
     check rustc
     check rustfmt
@@ -138,7 +168,11 @@ 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
@@ -163,9 +197,9 @@ else
     checked=$((checked + 1))
     tmp_clone="$(mktemp -d)"
     if git clone --depth 1 https://github.com/XRPLF/actions.git "${tmp_clone}/actions" >/dev/null 2>&1; then
-        printf '  [ ok ] git clone over HTTPS\n'
+        printf '  ✅ git clone over HTTPS\n'
     else
-        printf '  [MISS] git clone over HTTPS\n'
+        printf '  ❌ git clone over HTTPS\n'
         missing+=("git-https-clone")
     fi
     rm -rf "${tmp_clone}"
@@ -173,9 +207,9 @@ fi
 
 echo
 if [ "${#missing[@]}" -eq 0 ]; then
-    echo "All ${checked} checked tools are present and runnable."
+    echo "✅ All ${checked} checked tools are present and runnable."
 else
-    echo "Missing or non-functional tools (${#missing[@]} of ${checked}):" >&2
+    echo "❌ Missing or non-functional tools (${#missing[@]} of ${checked}):" >&2
     for tool in "${missing[@]}"; do
         echo "  - ${tool}" >&2
     done

cmake/XrplCompiler.cmake

@@ -266,10 +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/XrplCov.cmake

@@ -44,6 +44,7 @@ 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"

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/profiles/default

@@ -1,10 +1,7 @@
 {% set os = detect_api.detect_os() %}
 {% set arch = detect_api.detect_arch() %}
 {% set compiler, version, compiler_exe = detect_api.detect_default_compiler() %}
-{% set compiler_version = version %}
-{% if os == "Linux" %}
 {% set compiler_version = detect_api.default_compiler_version(compiler, version) %}
-{% endif %}
 {% if os == "Macos" %}
 {# Minimum macOS the dependencies target. #}
 {# Without this, Conan builds each dependency against the (possibly newer) host SDK, so the #}

docs/build/environment.md

@@ -6,22 +6,52 @@ This document explains how to set one up.
 
 ## Tested compiler versions
 
-`xrpld` is built in the **C++23** dialect by default.
-Make sure your toolchain is recent enough — the compiler versions currently tested in CI are:
+`xrpld` is built in the **C++23** dialect by default, so your toolchain has to
+support it — see [compiler support for C++23][cpp23-support].
+The versions currently tested in CI are:
 
-| Compiler    | Version |
-| ----------- | ------- |
-| GCC         | 15.2    |
-| Clang       | 22      |
-| Apple Clang | 17      |
-| MSVC        | 19.44   |
+| Compiler    | Version            |
+| ----------- | ------------------ |
+| GCC         | 15.2               |
+| Clang       | 22                 |
+| Apple Clang | 21                 |
+| MSVC        | Visual Studio 2026 |
 
 LLVM tools (`clang-tidy` and `clang-format`) are also pinned to version 22.
 
+### Older compilers
+
 Older compilers may fail to build the latest `develop` code: the codebase now
 relies on C++23 features and has been adjusted for `clang-tidy`.
 If the latest code doesn't build for you, update your build toolchain first.
 
+If updating isn't an option for you, we do accept pull requests that fix builds
+on older compilers, as long as the change is small and doesn't make the code
+harder to read. What we can't promise is that older compilers will keep working:
+only the versions in the table above are tested in CI, and we won't hold back
+the use of C++23 features or add invasive workarounds to keep an untested
+compiler building. Treat support for anything outside the table as best-effort.
+
+## Required tools
+
+Besides a compiler, building `xrpld` requires:
+
+| Tool                                        | Minimum version |
+| ------------------------------------------- | --------------- |
+| [Git](https://git-scm.com/downloads)        | any recent      |
+| [Python](https://www.python.org/downloads/) | 3.11            |
+| [Conan](https://conan.io/downloads.html)    | 2.17            |
+| [CMake](https://cmake.org/download/)        | 3.16            |
+
+On Linux and macOS, the [Nix development shell](./nix.md) provides all of them
+(see below). On Windows they have to be installed manually.
+
+Once they are in place, verify that everything is installed and runnable with:
+
+```bash
+./bin/check-tools.sh
+```
+
 ## Linux and macOS
 
 The **recommended way** to get a development environment on Linux and macOS is
@@ -39,20 +69,15 @@ Clang. If you instead opt to use your system-wide Apple Clang (via
 below).
 
 See [Using the Nix development shell](./nix.md) for installation and usage
-details, including how to select a different compiler.
-
-> [!NOTE]
-> Using Nix is not mandatory. Any custom environment (Homebrew packages or
-> anything else) will continue to work, but then it is up to you to keep it in
-> sync with the environment used in CI. Nix unifies the development environment
-> for everyone and synchronizes updates, which is why we recommend it.
+details, including how to select a different compiler and why we recommend Nix
+over a hand-maintained environment.
 
 ### macOS: managing the Apple Clang version
 
 If you use your system-wide Apple Clang on macOS (via `nix develop .#apple-clang`),
 the compiler version is whatever your installed Xcode (or Command Line Tools)
 provides. The following command should return a version greater than or equal to
-the [minimum required](#tested-compiler-versions):
+the [tested one](#tested-compiler-versions):
 
 ```bash
 clang --version
@@ -89,23 +114,23 @@ building xrpld. You may want to install and pin a specific version of Xcode:
 Nix is not available on Windows, so the required tools have to be installed
 manually:
 
-- [Visual Studio 2022](https://visualstudio.microsoft.com/) with the
+- [Visual Studio 2026](https://visualstudio.microsoft.com/) with the
   **"Desktop development with C++"** workload — this provides MSVC and the
-  "x64 Native Tools Command Prompt".
+  "x64 Native Tools Command Prompt". CI configures CMake with the
+  `Visual Studio 18 2026` generator.
 - [Git for Windows](https://git-scm.com/download/win)
-- [Python 3.11](https://www.python.org/downloads/), or higher
-- [Conan 2.17](https://conan.io/downloads.html), or higher
-- [CMake 3.22](https://cmake.org/download/), or higher
-
-> [!NOTE]
-> Windows is used for development only and is not recommended for production.
+- Python, Conan, and CMake, at the versions listed in
+  [Required tools](#required-tools).
 
 ## Clang-tidy
 
 `clang-tidy` is required to run static analysis checks locally (see
 [CONTRIBUTING.md](../../CONTRIBUTING.md)). It is not required to build the
-project. This project currently uses `clang-tidy` version 22.
+project. The version this project uses is listed in
+[Tested compiler versions](#tested-compiler-versions).
 
-On Linux and macOS, the [Nix development shell](./nix.md) provides `clang-tidy`
-22 out of the box — run it via `run-clang-tidy`. No separate installation is
-needed.
+On Linux and macOS, the [Nix development shell](./nix.md) provides that exact
+version out of the box — run it via `run-clang-tidy`. No separate installation
+is needed.
+
+[cpp23-support]: https://en.cppreference.com/w/cpp/compiler_support/23

docs/build/nix.md

@@ -120,7 +120,7 @@ nix develop -c "$SHELL"
 >
 > If it doesn't, either adjust your shell configuration so it doesn't override `$PATH`, or use [direnv](#automatic-activation-with-direnv) (below), which loads the environment _after_ your shell config and so takes precedence regardless of the shell you use.
 
-## Building xrpld with Nix
+## Building xrpld in the Nix shell
 
 Once inside the Nix development shell, follow the standard [build instructions](../../BUILD.md#steps). The Nix shell provides all necessary tools (CMake, Ninja, Conan, etc.).
 
@@ -128,6 +128,28 @@ Coverage builds (`-Dcoverage=ON`) work in the `gcc` shell (and `gcc-plain` on Li
 each ships a `gcov` matching its compiler, since Nix's cc-wrapper does not expose one.
 The `clang` shells do not include `llvm-cov`, so use a `gcc` shell for coverage.
 
+## Conan configuration
+
+The shell runs [`conan/init.sh`](../../conan/init.sh) on entry, so
+[Set Up Conan](../../BUILD.md#set-up-conan) is already done for you. It installs
+into the shell's own Conan home: `CONAN_HOME=~/.conan2-nix`.
+
+### Prebuilt packages
+
+On **Linux**, the binaries on the `xrplf` remote are built in this same Nix
+environment — CI runs in Docker images that bundle the dev shell's toolchain (see
+[`nix/docker`](../../nix/docker)) — so `.#gcc` and `.#clang` can reuse them. The
+`-plain` shells do not match that toolchain's glibc, so binaries from the remote
+are not a reliable match there.
+
+On **macOS**, CI builds with Apple Clang, so the remote holds nothing for the Nix
+`clang` toolchain and dependencies are compiled locally. We do not publish
+Nix-built macOS binaries because a Conan package ID records the compiler version
+but not the nixpkgs revision.
+
+To compile everything from source, add `--build '*'` to the `conan install`
+command.
+
 ## Automatic Activation with direnv
 
 [direnv](https://direnv.net/) or [nix-direnv](https://github.com/nix-community/nix-direnv) can automatically activate the Nix development shell when you enter the repository directory.
@@ -142,14 +164,6 @@ The repository already ships an `.envrc` at its root that activates the Nix flak
 > [!NOTE]
 > direnv only caches the `.direnv` directory (already listed in `.gitignore`); no other repository files are affected.
 
-## Conan and Prebuilt Packages
-
-Please note that there is no guarantee that binaries from conan cache will work when using nix. If you encounter any errors, please use `--build '*'` to force conan to compile everything from source:
-
-```bash
-conan install .. --output-folder . --build '*' --settings build_type=Release
-```
-
 ## Updating `flake.lock` file
 
 To update `flake.lock` to the latest revision use `nix flake update` command.

docs/sample_chart.doc

@@ -1,24 +0,0 @@
-/*!
-    \page somestatechart Example state diagram
-
-    \startuml SomeState "my state diagram"
-    scale 600 width
-
-    [*] -> State1
-    State1 --> State2 : Succeeded
-    State1 --> [*] : Aborted
-    State2 --> State3 : Succeeded
-    State2 --> [*] : Aborted
-    state State3 {
-      state "Accumulate Enough Data\nLong State Name" as long1
-      long1 : Just a test
-      [*] --> long1
-      long1 --> long1 : New Data
-      long1 --> ProcessData : Enough Data
-    }
-    State3 --> State3 : Failed
-    State3 --> [*] : Succeeded / Save Result
-    State3 --> [*] : Aborted
-
-    \enduml
-*/

include/xrpl/basics/Archive.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <boost/filesystem.hpp>
+#include <filesystem>
 
 namespace xrpl {
 
@@ -13,6 +13,6 @@ namespace xrpl {
  * @throws runtime_error
  */
 void
-extractTarLz4(boost::filesystem::path const& src, boost::filesystem::path const& dst);
+extractTarLz4(std::filesystem::path const& src, std::filesystem::path const& dst);
 
 }  // namespace xrpl

include/xrpl/basics/Buffer.h

@@ -3,6 +3,7 @@
 #include <xrpl/basics/Slice.h>
 #include <xrpl/beast/utility/instrumentation.h>
 
+#include <algorithm>
 #include <cstdint>
 #include <cstring>
 #include <memory>
@@ -156,6 +157,19 @@ public:
     }
     /** @} */
 
+    /**
+     * Set every byte in the buffer to the given value.
+     *
+     * The size is unchanged, and this is a no-op on an empty buffer.
+     *
+     * @param value the byte to write to every position.
+     */
+    void
+    fill(std::uint8_t value) noexcept
+    {
+        std::fill_n(p_.get(), size_, value);
+    }
+
     /**
      * Reset the buffer.
      * All memory is deallocated. The resulting size is 0.
@@ -226,10 +240,4 @@ operator==(Buffer const& lhs, Buffer const& rhs) noexcept
     return std::memcmp(lhs.data(), rhs.data(), lhs.size()) == 0;
 }
 
-inline bool
-operator!=(Buffer const& lhs, Buffer const& rhs) noexcept
-{
-    return !(lhs == rhs);
-}
-
 }  // namespace xrpl

include/xrpl/basics/FileUtilities.h

@@ -1,24 +1,79 @@
 #pragma once
 
-#include <boost/filesystem.hpp>
-#include <boost/system/error_code.hpp>
-
 #include <cstddef>
+#include <filesystem>
 #include <optional>
 #include <string>
+#include <system_error>
 
 namespace xrpl {
 
 std::string
 getFileContents(
-    boost::system::error_code& ec,
-    boost::filesystem::path const& sourcePath,
+    std::error_code& ec,
+    std::filesystem::path const& sourcePath,
     std::optional<std::size_t> maxSize = std::nullopt);
 
 void
 writeFileContents(
-    boost::system::error_code& ec,
-    boost::filesystem::path const& destPath,
+    std::error_code& ec,
+    std::filesystem::path const& destPath,
     std::string const& contents);
 
+/**
+ * Generate a unique, non-existing path under @p base whose filename starts with
+ * @p prefix and ends with a random hex suffix.
+ *
+ * Attempts up to @p maxAttempts paths. Throws `std::runtime_error` if a unique
+ * path cannot be found or if the filesystem returns an error while checking for
+ * existence.
+ */
+std::filesystem::path
+uniqueRandomPath(
+    std::filesystem::path const& base,
+    std::string const& prefix = "",
+    std::size_t maxAttempts = 100);
+
+/**
+ * RAII temporary directory.
+ *
+ * The directory and all its contents are deleted when
+ * the instance of `TempDir` is destroyed.
+ */
+class TempDir
+{
+    std::filesystem::path path_;
+
+public:
+#if !GENERATING_DOCS
+    TempDir(TempDir const&) = delete;
+    TempDir&
+    operator=(TempDir const&) = delete;
+#endif
+
+    /**
+     * Construct a temporary directory.
+     */
+    TempDir();
+
+    /**
+     * Destroy a temporary directory.
+     */
+    ~TempDir();
+
+    /**
+     * Get the native path for the temporary directory.
+     */
+    [[nodiscard]] std::string
+    path() const;
+
+    /**
+     * Get the native path for a file.
+     *
+     * The file does not need to exist.
+     */
+    [[nodiscard]] std::string
+    file(std::string const& name) const;
+};
+
 }  // namespace xrpl

include/xrpl/basics/IntrusivePointer.h

@@ -96,9 +96,6 @@ public:
     SharedIntrusive&
     operator=(SharedIntrusive const& rhs);
 
-    bool
-    operator!=(std::nullptr_t) const;
-
     bool
     operator==(std::nullptr_t) const;
 

include/xrpl/basics/IntrusivePointer.ipp

@@ -111,13 +111,6 @@ SharedIntrusive<T>::operator=(SharedIntrusive<TT>&& rhs)
     return *this;
 }
 
-template <class T>
-bool
-SharedIntrusive<T>::operator!=(std::nullptr_t) const
-{
-    return this->get() != nullptr;
-}
-
 template <class T>
 bool
 SharedIntrusive<T>::operator==(std::nullptr_t) const

include/xrpl/basics/Log.h

@@ -3,8 +3,8 @@
 #include <xrpl/beast/utility/Journal.h>
 
 #include <boost/beast/core/string.hpp>
-#include <boost/filesystem.hpp>
 
+#include <filesystem>
 #include <fstream>
 #include <map>
 #include <memory>
@@ -84,7 +84,7 @@ private:
          * @return `true` if the file was opened.
          */
         bool
-        open(boost::filesystem::path const& path);
+        open(std::filesystem::path const& path);
 
         /**
          * Close and re-open the system file associated with the log
@@ -133,7 +133,7 @@ private:
 
     private:
         std::unique_ptr<std::ofstream> stream_;
-        boost::filesystem::path path_;
+        std::filesystem::path path_;
     };
 
     std::mutex mutable mutex_;
@@ -152,7 +152,7 @@ public:
     virtual ~Logs() = default;
 
     bool
-    open(boost::filesystem::path const& pathToLogFile);
+    open(std::filesystem::path const& pathToLogFile);
 
     beast::Journal::Sink&
     get(std::string const& name);

include/xrpl/basics/Number.h

@@ -304,7 +304,7 @@ concept Integral64 = std::is_same_v<T, std::int64_t> || std::is_same_v<T, std::u
  *      on-ledger are non-negative. This is due to implementation details of
  *      several operations which use unsigned arithmetic internally. This is
  *      sufficient to represent all valid XRP values (where the absolute value
- *      can not exceed INITIAL_XRP: 10^17), and MPT values (where the absolute
+ *      can not exceed kInitialXRP: 10^17), and MPT values (where the absolute
  *      value can not exceed maxMPTokenAmount: 2^63-1).
  *
  * ---- Mantissa Range Switching ----
@@ -449,12 +449,6 @@ public:
             x.exponent_ == y.exponent_;
     }
 
-    friend constexpr bool
-    operator!=(Number const& x, Number const& y) noexcept
-    {
-        return !(x == y);
-    }
-
     friend constexpr bool
     operator<(Number const& l, Number const& r) noexcept
     {

include/xrpl/basics/SHAMapHash.h

@@ -85,12 +85,6 @@ public:
     }
 };
 
-inline bool
-operator!=(SHAMapHash const& x, SHAMapHash const& y)
-{
-    return !(x == y);
-}
-
 template <>
 inline std::size_t
 extract(SHAMapHash const& key)

include/xrpl/basics/Slice.h

@@ -208,12 +208,6 @@ operator==(Slice const& lhs, Slice const& rhs) noexcept
     return std::memcmp(lhs.data(), rhs.data(), lhs.size()) == 0;
 }
 
-inline bool
-operator!=(Slice const& lhs, Slice const& rhs) noexcept
-{
-    return !(lhs == rhs);
-}
-
 inline bool
 operator<(Slice const& lhs, Slice const& rhs) noexcept
 {

include/xrpl/basics/StringUtilities.h

@@ -2,7 +2,6 @@
 
 #include <xrpl/basics/Blob.h>
 
-#include <boost/format.hpp>
 #include <boost/utility/string_view.hpp>
 
 #include <array>
@@ -125,9 +124,31 @@ struct ParsedUrl
 bool
 parseUrl(ParsedUrl& pUrl, std::string const& strUrl);
 
+/**
+ * Remove leading and trailing ASCII whitespace.
+ *
+ * Whitespace is the fixed set " \t\n\v\f\r"; the current locale is not
+ * consulted, so the result depends only on the input.
+ *
+ * @param str The string to trim.
+ * @return @p str without leading or trailing whitespace.
+ */
 std::string
 trimWhitespace(std::string str);
 
+/**
+ * Fold ASCII upper case letters to lower case.
+ *
+ * Only 'A' through 'Z' are remapped; every other byte is left alone and the
+ * current locale is not consulted, so the result depends only on the input.
+ *
+ * @param str The string to fold.
+ * @return @p str with each ASCII upper case letter replaced by its lower case
+ *         equivalent.
+ */
+std::string
+toLower(std::string str);
+
 std::optional<std::uint64_t>
 toUInt64(std::string const& s);
 

include/xrpl/basics/partitioned_unordered_map.h

@@ -116,12 +116,6 @@ public:
         {
             return lhs.map == rhs.map && lhs.ait == rhs.ait && lhs.mit == rhs.mit;
         }
-
-        friend bool
-        operator!=(Iterator const& lhs, Iterator const& rhs)
-        {
-            return !(lhs == rhs);
-        }
     };
 
     struct ConstIterator
@@ -189,12 +183,6 @@ public:
         {
             return lhs.map == rhs.map && lhs.ait == rhs.ait && lhs.mit == rhs.mit;
         }
-
-        friend bool
-        operator!=(ConstIterator const& lhs, ConstIterator const& rhs)
-        {
-            return !(lhs == rhs);
-        }
     };
 
 private:

include/xrpl/beast/container/detail/aged_ordered_container.h

@@ -1038,25 +1038,6 @@ public:
                Compare,
                OtherAllocator> const& other) const;
 
-    template <
-        bool OtherIsMulti,
-        bool OtherIsMap,
-        class OtherT,
-        class OtherDuration,
-        class OtherAllocator>
-    bool
-    operator!=(AgedOrderedContainer<
-               OtherIsMulti,
-               OtherIsMap,
-               Key,
-               OtherT,
-               OtherDuration,
-               Compare,
-               OtherAllocator> const& other) const
-    {
-        return !(this->operator==(other));
-    }
-
     template <
         bool OtherIsMulti,
         bool OtherIsMap,

include/xrpl/beast/container/detail/aged_unordered_container.h

@@ -1340,28 +1340,6 @@ public:
                OtherAllocator> const& other) const
         requires MaybeMulti;
 
-    template <
-        bool OtherIsMulti,
-        bool OtherIsMap,
-        class OtherKey,
-        class OtherT,
-        class OtherDuration,
-        class OtherHash,
-        class OtherAllocator>
-    bool
-    operator!=(AgedUnorderedContainer<
-               OtherIsMulti,
-               OtherIsMap,
-               OtherKey,
-               OtherT,
-               OtherDuration,
-               OtherHash,
-               KeyEqual,
-               OtherAllocator> const& other) const
-    {
-        return !(this->operator==(other));
-    }
-
 private:
     bool
     wouldExceed(size_type additional) const

include/xrpl/beast/core/List.h

@@ -82,13 +82,6 @@ public:
         return node_ == other.node_;
     }
 
-    template <typename M>
-    bool
-    operator!=(ListIterator<M> const& other) const noexcept
-    {
-        return !((*this) == other);
-    }
-
     reference
     operator*() const noexcept
     {

include/xrpl/beast/net/IPEndpoint.h

@@ -110,12 +110,6 @@ public:
     operator==(Endpoint const& lhs, Endpoint const& rhs);
     friend bool
     operator<(Endpoint const& lhs, Endpoint const& rhs);
-
-    friend bool
-    operator!=(Endpoint const& lhs, Endpoint const& rhs)
-    {
-        return !(lhs == rhs);
-    }
     friend bool
     operator>(Endpoint const& lhs, Endpoint const& rhs)
     {

include/xrpl/beast/rfc2616.h

@@ -11,6 +11,7 @@
 #include <cstddef>
 #include <iterator>
 #include <string>
+#include <string_view>
 #include <vector>
 
 namespace beast::rfc2616 {
@@ -186,7 +187,7 @@ splitCommas(FwdIt first, FwdIt last)
 
 template <class Result = std::vector<std::string>>
 Result
-splitCommas(boost::beast::string_view const& s)
+splitCommas(std::string_view s)
 {
     return splitCommas(s.begin(), s.end());
 }
@@ -229,12 +230,6 @@ public:
         return other.it_ == it_ && other.end_ == end_ && other.value_.size() == value_.size();
     }
 
-    bool
-    operator!=(ListIterator const& other) const
-    {
-        return !(*this == other);
-    }
-
     reference
     operator*() const
     {

include/xrpl/beast/unit_test/reporter.h

@@ -8,7 +8,6 @@
 #include <xrpl/beast/unit_test/runner.h>
 #include <xrpl/beast/unit_test/suite_info.h>
 
-#include <boost/lexical_cast.hpp>
 #include <boost/optional.hpp>
 
 #include <algorithm>
@@ -188,7 +187,7 @@ Reporter<Unused>::fmtdur(clock_type::duration const& d)
     using namespace std::chrono;
     auto const ms = duration_cast<milliseconds>(d);
     if (ms < seconds{1})
-        return boost::lexical_cast<std::string>(ms.count()) + "ms";
+        return std::to_string(ms.count()) + "ms";
     std::stringstream ss;
     ss << std::fixed << std::setprecision(1) << (ms.count() / 1000.) << "s";
     return ss.str();

include/xrpl/beast/unit_test/suite.h

@@ -6,11 +6,10 @@
 
 #include <xrpl/beast/unit_test/runner.h>
 
-#include <boost/filesystem.hpp>
-#include <boost/lexical_cast.hpp>
 #include <boost/throw_exception.hpp>
 
 #include <exception>
+#include <filesystem>
 #include <memory>
 #include <ostream>
 #include <sstream>
@@ -27,10 +26,10 @@ makeReason(String const& reason, char const* file, int line)
     std::string s(reason);
     if (!s.empty())
         s.append(": ");
-    namespace fs = boost::filesystem;
+    namespace fs = std::filesystem;
     s.append(fs::path{file}.filename().string());
     s.append("(");
-    s.append(boost::lexical_cast<std::string>(line));
+    s.append(std::to_string(line));
     s.append(")");
     return s;
 }

include/xrpl/beast/utility/temp_dir.h

@@ -1,71 +0,0 @@
-#pragma once
-
-#include <boost/filesystem.hpp>
-
-#include <string>
-
-namespace beast {
-
-/**
- * RAII temporary directory.
- *
- * The directory and all its contents are deleted when
- * the instance of `temp_dir` is destroyed.
- */
-class TempDir
-{
-    boost::filesystem::path path_;
-
-public:
-#if !GENERATING_DOCS
-    TempDir(TempDir const&) = delete;
-    TempDir&
-    operator=(TempDir const&) = delete;
-#endif
-
-    /**
-     * Construct a temporary directory.
-     */
-    TempDir()
-    {
-        auto const dir = boost::filesystem::temp_directory_path();
-        do
-        {
-            path_ = dir / boost::filesystem::unique_path();
-        } while (boost::filesystem::exists(path_));
-        boost::filesystem::create_directory(path_);
-    }
-
-    /**
-     * Destroy a temporary directory.
-     */
-    ~TempDir()
-    {
-        // use non-throwing calls in the destructor
-        boost::system::error_code ec;
-        boost::filesystem::remove_all(path_, ec);
-        // TODO: warn/notify if ec set ?
-    }
-
-    /**
-     * Get the native path for the temporary directory
-     */
-    [[nodiscard]] std::string
-    path() const
-    {
-        return path_.string();
-    }
-
-    /**
-     * Get the native path for the a file.
-     *
-     * The file does not need to exist.
-     */
-    [[nodiscard]] std::string
-    file(std::string const& name) const
-    {
-        return (path_ / name).string();
-    }
-};
-
-}  // namespace beast

include/xrpl/conditions/Condition.h

@@ -92,10 +92,4 @@ operator==(Condition const& lhs, Condition const& rhs)
         lhs.fingerprint == rhs.fingerprint;
 }
 
-inline bool
-operator!=(Condition const& lhs, Condition const& rhs)
-{
-    return !(lhs == rhs);
-}
-
 }  // namespace xrpl::cryptoconditions

include/xrpl/conditions/Fulfillment.h

@@ -93,12 +93,6 @@ operator==(Fulfillment const& lhs, Fulfillment const& rhs)
         lhs.fingerprint() == rhs.fingerprint();
 }
 
-inline bool
-operator!=(Fulfillment const& lhs, Fulfillment const& rhs)
-{
-    return !(lhs == rhs);
-}
-
 /**
  * Determine whether the given fulfillment and condition match
  */

include/xrpl/config/BasicConfig.h

@@ -2,7 +2,6 @@
 
 #include <xrpl/basics/contract.h>
 
-#include <boost/beast/core/string.hpp>
 #include <boost/lexical_cast.hpp>
 
 #include <algorithm>

include/xrpl/core/PerfLog.h

@@ -4,10 +4,9 @@
 #include <xrpl/core/Job.h>
 #include <xrpl/json/json_value.h>
 
-#include <boost/filesystem.hpp>
-
 #include <chrono>
 #include <cstdint>
+#include <filesystem>
 #include <functional>
 #include <memory>
 #include <string>
@@ -44,7 +43,7 @@ public:
      */
     struct Setup
     {
-        boost::filesystem::path perfLog;
+        std::filesystem::path perfLog;
         // log_interval is in milliseconds to support faster testing.
         milliseconds logInterval{seconds(1)};
     };
@@ -149,7 +148,7 @@ public:
 };
 
 PerfLog::Setup
-setupPerfLog(Section const& section, boost::filesystem::path const& configDir);
+setupPerfLog(Section const& section, std::filesystem::path const& configDir);
 
 std::unique_ptr<PerfLog>
 makePerfLog(

include/xrpl/json/Output.h

@@ -1,20 +1,19 @@
 #pragma once
 
-#include <boost/beast/core/string.hpp>
-
 #include <functional>
 #include <string>
+#include <string_view>
 
 namespace json {
 
 class Value;
 
-using Output = std::function<void(boost::beast::string_view const&)>;
+using Output = std::function<void(std::string_view)>;
 
 inline Output
 stringOutput(std::string& s)
 {
-    return [&](boost::beast::string_view const& b) { s.append(b.data(), b.size()); };
+    return [&](std::string_view b) { s.append(b.data(), b.size()); };
 }
 
 /**

include/xrpl/json/json_value.h

@@ -4,6 +4,7 @@
 #include <xrpl/json/json_forwards.h>
 
 #include <cstring>
+#include <iterator>
 #include <limits>
 #include <map>
 #include <string>
@@ -72,36 +73,18 @@ operator==(StaticString x, StaticString y)
     return strcmp(x.cStr(), y.cStr()) == 0;
 }
 
-inline bool
-operator!=(StaticString x, StaticString y)
-{
-    return !(x == y);
-}
-
 inline bool
 operator==(std::string const& x, StaticString y)
 {
     return strcmp(x.c_str(), y.cStr()) == 0;
 }
 
-inline bool
-operator!=(std::string const& x, StaticString y)
-{
-    return !(x == y);
-}
-
 inline bool
 operator==(StaticString x, std::string const& y)
 {
     return y == x;
 }
 
-inline bool
-operator!=(StaticString x, std::string const& y)
-{
-    return !(y == x);
-}
-
 /**
  * @brief Represents a <a HREF="http://www.json.org">JSON</a> value.
  *
@@ -489,12 +472,6 @@ toJson(xrpl::Number const& number)
 bool
 operator==(Value const&, Value const&);
 
-inline bool
-operator!=(Value const& x, Value const& y)
-{
-    return !(x == y);
-}
-
 bool
 operator<(Value const&, Value const&);
 
@@ -548,6 +525,7 @@ public:
 class ValueIteratorBase
 {
 public:
+    using iterator_category = std::bidirectional_iterator_tag;
     using size_t = unsigned int;
     using difference_type = int;
     using SelfType = ValueIteratorBase;
@@ -562,12 +540,6 @@ public:
         return isEqual(other);
     }
 
-    bool
-    operator!=(SelfType const& other) const
-    {
-        return !isEqual(other);
-    }
-
     /**
      * Return either the index or the member name of the referenced value as a
      * Value.

include/xrpl/ledger/BookDirs.h

@@ -49,12 +49,6 @@ public:
     bool
     operator==(const_iterator const& other) const;
 
-    bool
-    operator!=(const_iterator const& other) const
-    {
-        return !(*this == other);
-    }
-
     reference
     operator*() const;
 

include/xrpl/ledger/CanonicalTXSet.h

@@ -59,12 +59,6 @@ private:
             return lhs.txId_ == rhs.txId_;
         }
 
-        friend bool
-        operator!=(Key const& lhs, Key const& rhs)
-        {
-            return !(lhs == rhs);
-        }
-
         [[nodiscard]] uint256 const&
         getAccount() const
         {

include/xrpl/ledger/Dir.h

@@ -59,12 +59,6 @@ public:
     bool
     operator==(ConstIterator const& other) const;
 
-    bool
-    operator!=(ConstIterator const& other) const
-    {
-        return !(*this == other);
-    }
-
     reference
     operator*() const;
 

include/xrpl/ledger/View.h

@@ -35,6 +35,11 @@ enum class SkipEntry : bool { No = false, Yes };
 //
 //------------------------------------------------------------------------------
 
+/**
+ * Whether an expiration check should be inclusive or exclusive.
+ */
+enum class ExpiryComparison { Inclusive, Exclusive };
+
 /**
  * Determines whether the given expiration time has passed.
  *
@@ -54,11 +59,16 @@ enum class SkipEntry : bool { No = false, Yes };
  *
  * @param view The ledger whose parent time is used as the clock.
  * @param exp The optional expiration time we want to check.
+ * @param comparison Whether the boundary is inclusive (`now >= exp`, the
+ *                   default) or exclusive (`now > exp`).
  *
  * @return `true` if `exp` is in the past; `false` otherwise.
  */
 [[nodiscard]] bool
-hasExpired(ReadView const& view, std::optional<std::uint32_t> const& exp);
+hasExpired(
+    ReadView const& view,
+    std::optional<std::uint32_t> const& exp,
+    ExpiryComparison comparison = ExpiryComparison::Inclusive);
 
 // Note, depth parameter is used to limit the recursion depth
 [[nodiscard]] bool
@@ -68,6 +78,13 @@ isVaultPseudoAccountFrozen(
     MPTIssue const& mptShare,
     std::uint8_t depth);
 
+[[nodiscard]] bool
+isVaultPseudoAccountFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    SLE const& issuanceSle,
+    std::uint8_t depth);
+
 [[nodiscard]] bool
 isLPTokenFrozen(
     ReadView const& view,
@@ -75,6 +92,26 @@ isLPTokenFrozen(
     Asset const& asset,
     Asset const& asset2);
 
+/**
+ * Check whether an AMM LPToken may be transferred between @p from and @p to.
+ *
+ * @p lpTokenIssuer is the issuer of the LPToken being moved. If it is not an
+ * AMM account the token is not an LPToken and the transfer is unconditionally
+ * permitted. Otherwise, for each MPT pool asset of that AMM, canTransfer() must
+ * permit the transfer (which exempts the MPT issuer). Non-MPT pool assets are
+ * always transferable by this check, so it is implicitly gated by
+ * featureMPTokensV2 (MPTs can only be AMM pool assets once V2 is enabled).
+ *
+ * @return tesSUCCESS if permitted, otherwise the canTransfer() failure code
+ * (e.g. tecNO_AUTH) of the first MPT pool asset that disallows it.
+ */
+[[nodiscard]] TER
+canTransferLPToken(
+    ReadView const& view,
+    AccountID const& from,
+    AccountID const& to,
+    AccountID const& lpTokenIssuer);
+
 // Return the list of enabled amendments
 [[nodiscard]] std::set<uint256>
 getEnabledAmendments(ReadView const& view);

include/xrpl/ledger/detail/ReadViewFwdRange.h

@@ -85,9 +85,6 @@ public:
         bool
         operator==(Iterator const& other) const;
 
-        bool
-        operator!=(Iterator const& other) const;
-
         // Can throw
         reference
         operator*() const;

include/xrpl/ledger/detail/ReadViewFwdRange.ipp

@@ -64,13 +64,6 @@ ReadViewFwdRange<ValueType>::Iterator::operator==(Iterator const& other) const
     return impl_ == other.impl_;
 }
 
-template <class ValueType>
-bool
-ReadViewFwdRange<ValueType>::Iterator::operator!=(Iterator const& other) const
-{
-    return !(*this == other);
-}
-
 template <class ValueType>
 auto
 ReadViewFwdRange<ValueType>::Iterator::operator*() const -> reference

include/xrpl/ledger/helpers/AMMHelpers.h

@@ -226,7 +226,7 @@ getAMMOfferStartWithTakerGets(
 
     auto getAmounts = [&pool, &tfee](Number const& nTakerGetsProposed) {
         // Round downward to minimize the offer and to maximize the quality.
-        // This has the most impact when takerGets is XRP.
+        // This has the most impact when takerGets is integral.
         auto const takerGets =
             toAmount<TOut>(getAsset(pool.out), nTakerGetsProposed, Number::RoundingMode::Downward);
         return TAmounts<TIn, TOut>{swapAssetOut(pool, takerGets, tfee), takerGets};
@@ -294,7 +294,7 @@ getAMMOfferStartWithTakerPays(
 
     auto getAmounts = [&pool, &tfee](Number const& nTakerPaysProposed) {
         // Round downward to minimize the offer and to maximize the quality.
-        // This has the most impact when takerPays is XRP.
+        // This has the most impact when takerPays is integral.
         auto const takerPays =
             toAmount<TIn>(getAsset(pool.in), nTakerPaysProposed, Number::RoundingMode::Downward);
         return TAmounts<TIn, TOut>{takerPays, swapAssetIn(pool, takerPays, tfee)};
@@ -313,11 +313,11 @@ getAMMOfferStartWithTakerPays(
  * is equal to LOB quality (in this case AMM offer quality is
  * better than LOB quality) or AMM offer is equal to LOB quality
  * (in this case SPQ is better than LOB quality).
- * Pre-amendment code calculates takerPays first. If takerGets is XRP,
- * it is rounded down, which results in worse offer quality than
- * LOB quality, and the offer might fail to generate.
- * Post-amendment code calculates the XRP offer side first. The result
- * is rounded down, which makes the offer quality better.
+ * Pre-amendment code calculates takerPays first. If takerGets is the
+ * economically coarser integral side, it is rounded down, which results in
+ * worse offer quality than LOB quality, and the offer might fail to generate.
+ * Post-amendment code calculates the economically coarser integral offer side
+ * first. The result is rounded down, which makes the offer quality better.
  *   It might not be possible to match either SPQ or AMM offer to LOB
  * quality. This generally happens at higher fees.
  * @param pool AMM pool balances
@@ -396,10 +396,18 @@ changeSpotPriceQuality(
         return std::nullopt;
     }
 
-    // Generate the offer starting with XRP side. Return seated offer amounts
-    // if the offer can be generated, otherwise nullopt.
     auto amounts = [&]() {
-        if (isXRP(getAsset(pool.out)))
+        bool const inIntegral = getAsset(pool.in).integral();
+        bool const outIntegral = getAsset(pool.out).integral();
+
+        // Preserve historical behavior for fractional pairs and XRP/IOU-style
+        // one-integral-side pairs. For two integral assets, pick the side whose
+        // minimum unit is economically coarser at this quality.
+        //
+        // Quality::rate() is input units per output unit, so one output unit is
+        // coarser when it costs at least one input unit. Ties use takerGets,
+        // matching the historical XRP-output behavior.
+        if (outIntegral && (!inIntegral || Number(quality.rate()) >= 1))
             return getAMMOfferStartWithTakerGets(pool, quality, tfee);
         return getAMMOfferStartWithTakerPays(pool, quality, tfee);
     }();

include/xrpl/ledger/helpers/CredentialHelpers.h

@@ -7,6 +7,7 @@
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/ReadView.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Rules.h>
 #include <xrpl/protocol/STArray.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 #include <xrpl/protocol/STTx.h>
@@ -34,7 +35,7 @@ deleteSLE(ApplyView& view, SLE::ref sleCredential, beast::Journal j);
 
 // Amendment and parameters checks for sfCredentialIDs field
 NotTEC
-checkFields(STTx const& tx, beast::Journal j);
+checkFields(STTx const& tx, Rules const& rules, beast::Journal j);
 
 // Accessing the ledger to check if provided credentials are valid. Do not use
 // in doApply (only in preclaim) since it does not remove expired credentials.

include/xrpl/ledger/helpers/MPTokenHelpers.h

@@ -29,6 +29,9 @@ namespace xrpl {
 [[nodiscard]] bool
 isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
 
+[[nodiscard]] bool
+isGlobalFrozen(SLE const& issuanceSle);
+
 /**
  * Returns true if @p account's MPToken for @p mptIssue carries the
  * individual-lock flag (lsfMPTLocked).
@@ -40,9 +43,29 @@ isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
  * receive tokens — it combines isIndividualFrozen, isGlobalFrozen, and
  * isVaultPseudoAccountFrozen into a single complete check.
  */
+
 [[nodiscard]] bool
 isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
 
+[[nodiscard]] bool
+isIndividualFrozen(SLE const& mptSle);
+
+/**
+ * Returns true if @p account cannot send or receive tokens of @p mptIssue
+ * because a freeze applies. This is the complete check callers should use
+ * before moving MPT value: it combines @ref isGlobalFrozen (issuance-level
+ * lock), @ref isIndividualFrozen (per-holder lock bit), and the transitive
+ * vault pseudo-account check (if @p mptIssue is a vault share, the underlying
+ * asset is checked, and so on recursively up to @c maxAssetCheckDepth).
+ *
+ * The @c SLE overload takes an already-loaded ltMPTOKEN or ltMPTOKEN_ISSUANCE
+ * ledger entry; for ltMPTOKEN it can skip the per-holder individual-lock lookup.
+ * @ref isAnyFrozen answers the same question for a set of accounts and returns true
+ * if the freeze applies to any of them.
+ *
+ * @param depth Current recursion depth for the vault-share walk. Callers
+ * outside this module should leave it at the default.
+ */
 [[nodiscard]] bool
 isFrozen(
     ReadView const& view,
@@ -50,6 +73,18 @@ isFrozen(
     MPTIssue const& mptIssue,
     std::uint8_t depth = 0);
 
+/**
+ * SLE overload: pass an already-loaded ltMPTOKEN (holder row) or
+ * ltMPTOKEN_ISSUANCE to reuse it for the freeze checks and avoid re-reading
+ * the same object. For an ltMPTOKEN, @p sle is used directly for the
+ * individual-lock check and the issuance is read once for global-freeze and
+ * vault-pseudo-account. For an ltMPTOKEN_ISSUANCE, @p sle is used directly
+ * for global-freeze and vault-pseudo-account, and the caller's holder row is
+ * read for the individual-lock check.
+ */
+[[nodiscard]] bool
+isFrozen(ReadView const& view, AccountID const& account, SLE const& sle, std::uint8_t depth = 0);
+
 [[nodiscard]] bool
 isAnyFrozen(
     ReadView const& view,
@@ -261,6 +296,14 @@ checkCreateMPT(
     xrpl::MPTIssue const& mptIssue,
     xrpl::AccountID const& holder,
     SLE::ref sponsorSle,
+    std::uint32_t flags,
+    beast::Journal j);
+
+TER
+checkCreateMPT(
+    xrpl::ApplyView& view,
+    xrpl::MPTIssue const& mptIssue,
+    xrpl::AccountID const& holder,
     beast::Journal j);
 
 //------------------------------------------------------------------------------

include/xrpl/ledger/helpers/VaultHelpers.h

@@ -6,10 +6,13 @@
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 
+#include <cstdint>
 #include <optional>
 
 namespace xrpl {
 
+class STTx;
+
 /**
  * From the perspective of a vault, return the number of shares to give
  * depositor when they offer a fixed amount of assets. Note, since shares are
@@ -123,4 +126,82 @@ isSoleShareholder(ReadView const& view, AccountID const& account, SLE::const_ref
 [[nodiscard]] VaultVersion
 getVaultVersion(SLE::const_ref vault);
 
+/**
+ * Resolves the VaultKind of a vault SLE. Returns VaultKind::ClosedEnded when
+ * sfVaultKind is present and equal to that value; anything else (including an
+ * absent field or an unrecognised value) is treated as VaultKind::OpenEnded.
+ *
+ * @param vault The vault SLE.
+ */
+[[nodiscard]] VaultKind
+getVaultKind(SLE::const_ref vault);
+
+/**
+ * Reads sfVaultKind from a transaction. An absent field resolves to
+ * VaultKind::OpenEnded (matching the on-ledger default); any unrecognised
+ * value is also treated as VaultKind::OpenEnded, mirroring the SLE overload.
+ * Callers that need to reject out-of-range values (e.g. preflight) should
+ * gate on isValidVaultKind() first.
+ *
+ * @param tx The transaction.
+ */
+[[nodiscard]] VaultKind
+getVaultKind(STTx const& tx);
+
+/**
+ * Returns true iff sfVaultKind is either absent from @p tx or is present and
+ * equal to a recognised VaultKind enumerator. Intended for use in preflight
+ * to reject malformed transactions before decoding with getVaultKind().
+ *
+ * @param tx The transaction.
+ */
+[[nodiscard]] bool
+isValidVaultKind(STTx const& tx);
+
+/**
+ * Returns true iff the (SubscriptionDate, RedemptionDate) gap of a
+ * closed-ended vault satisfies
+ * kMinInvestmentPeriod <= (red - sub) < kMaxInvestmentPeriod. The arithmetic
+ * is performed in std::int64_t so that @p sub near UINT32_MAX does not
+ * overflow. Shared by VaultCreate::preflight and the ValidVault invariant.
+ *
+ * @param sub The value of sfSubscriptionDate.
+ * @param red The value of sfRedemptionDate.
+ */
+[[nodiscard]] bool
+isValidClosedEndedGap(std::uint32_t sub, std::uint32_t red);
+
+/**
+ * Returns the current lifecycle phase of a vault. Open-ended
+ * vaults are always NoPhase. For closed-ended vaults the phase is derived
+ * from the parent ledger close time and the vault's immutable
+ * SubscriptionDate and RedemptionDate.
+ *
+ * @param view The ledger view whose parent close time is used as the clock.
+ * @param vault The vault SLE.
+ */
+[[nodiscard]] VaultPhase
+getVaultPhase(ReadView const& view, SLE::const_ref vault);
+
+/**
+ * Raw-fields overload of getVaultPhase. Derives the phase from an already
+ * decomposed vault snapshot: an absent or non-ClosedEnded @p vaultKind
+ * resolves to VaultPhase::NoPhase; otherwise the phase is computed from
+ * @p subscriptionDate and @p redemptionDate against the view's parent
+ * close time using the same boundary semantics as the SLE overload
+ * (Subscription is inclusive of now == SubscriptionDate; Investment starts
+ * strictly after).
+ *
+ * @param view The ledger view whose parent close time is used as the clock.
+ * @param vaultKind The value of sfVaultKind, or nullopt if absent.
+ * @param subscriptionDate The value of sfSubscriptionDate, or nullopt if absent.
+ * @param redemptionDate The value of sfRedemptionDate, or nullopt if absent.
+ */
+[[nodiscard]] VaultPhase
+getVaultPhase(
+    ReadView const& view,
+    std::optional<std::uint8_t> vaultKind,
+    std::optional<std::uint32_t> subscriptionDate,
+    std::optional<std::uint32_t> redemptionDate);
+
 }  // namespace xrpl

include/xrpl/net/HTTPClientSSLContext.h

@@ -8,11 +8,11 @@
 #include <boost/asio.hpp>
 #include <boost/asio/ip/tcp.hpp>
 #include <boost/asio/ssl.hpp>
-#include <boost/format.hpp>
 
 #include <openssl/err.h>
 #include <openssl/tls1.h>
 
+#include <format>
 #include <stdexcept>
 #include <string>
 #include <type_traits>
@@ -38,8 +38,8 @@ public:
 
             if (ec && sslVerifyDir.empty())
             {
-                Throw<std::runtime_error>(boost::str(
-                    boost::format("Failed to set_default_verify_paths: %s") % ec.message()));
+                Throw<std::runtime_error>(
+                    std::format("Failed to set_default_verify_paths: {}", ec.message()));
             }
         }
         else
@@ -54,7 +54,7 @@ public:
             if (ec)
             {
                 Throw<std::runtime_error>(
-                    boost::str(boost::format("Failed to add verify path: %s") % ec.message()));
+                    std::format("Failed to add verify path: {}", ec.message()));
             }
         }
     }

include/xrpl/proto/xrpl.proto

@@ -1,10 +1,10 @@
 syntax = "proto2";
 package protocol;
 
-// Unused numbers in the list below may have been used previously. Please don't
-// reassign them for reuse unless you are 100% certain that there won't be a
-// conflict. Even if you're sure, it's probably best to assign a new type.
 enum MessageType {
+  // Previously used - don't reuse.
+  reserved 0 to 1, 4, 6 to 14, 16 to 29, 36 to 40, 43 to 54, 61 to 62;
+
   mtMANIFESTS = 2;
   mtPING = 3;
   mtCLUSTER = 5;
@@ -17,7 +17,6 @@ enum MessageType {
   mtHAVE_SET = 35;
   mtVALIDATION = 41;
   mtGET_OBJECTS = 42;
-  mtVALIDATOR_LIST = 54;
   mtSQUELCH = 55;
   mtVALIDATOR_LIST_COLLECTION = 56;
   mtPROOF_PATH_REQ = 57;
@@ -162,14 +161,6 @@ message TMHaveTransactionSet {
   required bytes hash = 2;
 }
 
-// Validator list (UNL)
-message TMValidatorList {
-  required bytes manifest = 1;
-  required bytes blob = 2;
-  required bytes signature = 3;
-  required uint32 version = 4;
-}
-
 // Validator List v2
 message ValidatorBlobInfo {
   optional bytes manifest = 1;

include/xrpl/protocol/AMMCore.h

@@ -47,7 +47,7 @@ ammLPTIssue(Asset const& asset1, Asset const& asset2, AccountID const& ammAccoun
 
 /**
  * Validate the amount.
- * If validZero is false and amount is beast::zero then invalid amount.
+ * If validZero is false and amount is beast::kZero then invalid amount.
  * Return error code if invalid amount.
  * If pair then validate amount's issue matches one of the pair's issue.
  */

include/xrpl/protocol/AmountConversions.h

@@ -154,7 +154,7 @@ T
 toAmount(Asset const& asset, Number const& n, Number::RoundingMode mode = Number::getround())
 {
     SaveNumberRoundMode const rm(Number::getround());
-    if (isXRP(asset))
+    if (asset.integral())
         Number::setround(mode);
 
     if constexpr (std::is_same_v<IOUAmount, T>)

include/xrpl/protocol/Protocol.h

@@ -9,6 +9,7 @@
 #include <mpt_protocol.h>
 #include <secp256k1_mpt.h>
 
+#include <chrono>
 #include <cstddef>
 #include <cstdint>
 
@@ -327,6 +328,36 @@ enum class VaultVersion : uint8_t {
     CashBasis,
 };
 
+/**
+ * Vault kind. Distinguishes closed-ended vaults from the default open-ended
+ * kind. Persisted as sfVaultKind (UINT8); absent means OpenEnded.
+ */
+enum class VaultKind : std::uint8_t {
+    OpenEnded = 0,
+    ClosedEnded = 1,
+};
+
+/**
+ * Lifecycle phase of a vault. Open-ended vaults are always NoPhase; the other
+ * three values are the phases of a closed-ended vault.
+ */
+enum class VaultPhase : std::uint8_t {
+    NoPhase = 0,
+    Subscription,
+    Investment,
+    Redemption,
+};
+
+/**
+ * Bounds on the length of a closed-ended vault's Investment phase
+ * (RedemptionDate - SubscriptionDate). At vault creation the gap must satisfy
+ * kMinInvestmentPeriod <= gap < kMaxInvestmentPeriod.
+ */
+constexpr std::uint32_t kMinInvestmentPeriod =
+    std::chrono::seconds{std::chrono::minutes{1}}.count();
+// This is 946708560 seconds which 30 x 365.2425 days (the average length of a Gregorian year).
+constexpr std::uint32_t kMaxInvestmentPeriod = std::chrono::seconds{std::chrono::years{30}}.count();
+
 /**
  * Maximum recursion depth for vault shares being put as an asset inside
  * another vault; counted from 0

include/xrpl/protocol/Quality.h

@@ -75,13 +75,6 @@ operator==(TAmounts<In, Out> const& lhs, TAmounts<In, Out> const& rhs) noexcept
     return lhs.in == rhs.in && lhs.out == rhs.out;
 }
 
-template <class In, class Out>
-bool
-operator!=(TAmounts<In, Out> const& lhs, TAmounts<In, Out> const& rhs) noexcept
-{
-    return !(lhs == rhs);
-}
-
 //------------------------------------------------------------------------------
 
 // XRPL specific constant used for parsing qualities and other things
@@ -271,12 +264,6 @@ public:
         return lhs.value_ == rhs.value_;
     }
 
-    friend bool
-    operator!=(Quality const& lhs, Quality const& rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
     friend std::ostream&
     operator<<(std::ostream& os, Quality const& quality)
     {

include/xrpl/protocol/QualityFunction.h

@@ -60,6 +60,15 @@ public:
     std::optional<Number>
     outFromAvgQ(Quality const& quality);
 
+    /**
+     * Return whether `out` produces at least the requested
+     * average quality.
+     * @param quality requested average quality (quality limit)
+     * @param out output amount to test
+     */
+    [[nodiscard]] bool
+    satisfiesAvgQ(Quality const& quality, Number const& out) const;
+
     /**
      * Return true if the quality function is constant
      */

include/xrpl/protocol/Rules.h

@@ -98,9 +98,6 @@ public:
      */
     bool
     operator==(Rules const&) const;
-
-    bool
-    operator!=(Rules const& other) const;
 };
 
 std::optional<Rules> const&

include/xrpl/protocol/STAmount.h

@@ -642,12 +642,6 @@ operator==(STAmount const& lhs, STAmount const& rhs);
 bool
 operator<(STAmount const& lhs, STAmount const& rhs);
 
-inline bool
-operator!=(STAmount const& lhs, STAmount const& rhs)
-{
-    return !(lhs == rhs);
-}
-
 inline bool
 operator>(STAmount const& lhs, STAmount const& rhs)
 {

include/xrpl/protocol/STArray.h

@@ -133,9 +133,6 @@ public:
     bool
     operator==(STArray const& s) const;
 
-    bool
-    operator!=(STArray const& s) const;
-
     iterator
     erase(iterator pos);
 
@@ -283,12 +280,6 @@ STArray::operator==(STArray const& s) const
     return v_ == s.v_;
 }
 
-inline bool
-STArray::operator!=(STArray const& s) const
-{
-    return v_ != s.v_;
-}
-
 inline STArray::iterator
 STArray::erase(iterator pos)
 {

include/xrpl/protocol/STBase.h

@@ -140,8 +140,6 @@ public:
 
     bool
     operator==(STBase const& t) const;
-    bool
-    operator!=(STBase const& t) const;
 
     template <class D>
     D&

include/xrpl/protocol/STCurrency.h

@@ -93,12 +93,6 @@ operator==(STCurrency const& lhs, STCurrency const& rhs)
     return lhs.currency() == rhs.currency();
 }
 
-inline bool
-operator!=(STCurrency const& lhs, STCurrency const& rhs)
-{
-    return !operator==(lhs, rhs);
-}
-
 inline bool
 operator<(STCurrency const& lhs, STCurrency const& rhs)
 {

include/xrpl/protocol/STObject.h

@@ -432,8 +432,6 @@ public:
 
     bool
     operator==(STObject const& o) const;
-    bool
-    operator!=(STObject const& o) const;
 
     class FieldErr;
 
@@ -667,36 +665,6 @@ public:
         return !lhs.engaged() || *lhs == *rhs;
     }
 
-    friend bool
-    operator!=(OptionalProxy const& lhs, std::nullopt_t) noexcept
-    {
-        return !(lhs == std::nullopt);
-    }
-
-    friend bool
-    operator!=(std::nullopt_t, OptionalProxy const& rhs) noexcept
-    {
-        return !(rhs == std::nullopt);
-    }
-
-    friend bool
-    operator!=(OptionalProxy const& lhs, optional_type const& rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
-    friend bool
-    operator!=(optional_type const& lhs, OptionalProxy const& rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
-    friend bool
-    operator!=(OptionalProxy const& lhs, OptionalProxy const& rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
     // Emulate std::optional::value_or
     [[nodiscard]] value_type
     valueOr(value_type val) const;
@@ -1202,12 +1170,6 @@ STObject::setFieldH160(SField const& field, BaseUInt<160, Tag> const& v)
     }
 }
 
-inline bool
-STObject::operator!=(STObject const& o) const
-{
-    return !(*this == o);
-}
-
 template <typename T, typename V>
 V
 STObject::getFieldByValue(SField const& field) const

include/xrpl/protocol/STPathSet.h

@@ -115,9 +115,6 @@ public:
     bool
     operator==(STPathElement const& t) const;
 
-    bool
-    operator!=(STPathElement const& t) const;
-
 private:
     static std::size_t
     getHash(STPathElement const& element);
@@ -432,12 +429,6 @@ STPathElement::operator==(STPathElement const& t) const
         accountID_ == t.accountID_ && assetID_ == t.assetID_ && issuerID_ == t.issuerID_;
 }
 
-inline bool
-STPathElement::operator!=(STPathElement const& t) const
-{
-    return !operator==(t);
-}
-
 // ------------ STPath ------------
 
 inline STPath::STPath(std::vector<STPathElement> p) : path_(std::move(p))

include/xrpl/protocol/SeqProxy.h

@@ -123,12 +123,6 @@ public:
         return (lhs.value() == rhs.value());
     }
 
-    friend constexpr bool
-    operator!=(SeqProxy lhs, SeqProxy rhs)
-    {
-        return !(lhs == rhs);
-    }
-
     friend constexpr bool
     operator<(SeqProxy lhs, SeqProxy rhs)
     {

include/xrpl/protocol/Serializer.h

@@ -265,20 +265,10 @@ public:
         return v == data_;
     }
     bool
-    operator!=(Blob const& v) const
-    {
-        return v != data_;
-    }
-    bool
     operator==(Serializer const& v) const
     {
         return v.data_ == data_;
     }
-    bool
-    operator!=(Serializer const& v) const
-    {
-        return v.data_ != data_;
-    }
 
     static int
     decodeLengthLength(int b1);

include/xrpl/protocol/TxFlags.h

@@ -425,8 +425,7 @@ inline constexpr FlagValue tfDepositSubTx =
     ASF_FLAG(asfDefaultRipple, 8)                 \
     ASF_FLAG(asfDepositAuth, 9)                   \
     ASF_FLAG(asfAuthorizedNFTokenMinter, 10)      \
-    /*  11 is reserved for Hooks amendment */     \
-    /* ASF_FLAG(asfTshCollect, 11) */             \
+    /*  11 is unused */                           \
     ASF_FLAG(asfDisallowIncomingNFTokenOffer, 12) \
     ASF_FLAG(asfDisallowIncomingCheck, 13)        \
     ASF_FLAG(asfDisallowIncomingPayChan, 14)      \

include/xrpl/protocol/Units.h

@@ -258,13 +258,6 @@ public:
         return value_ == other;
     }
 
-    template <Compatible<ValueUnit> Other>
-    constexpr bool
-    operator!=(ValueUnit<unit_type, Other> const& other) const
-    {
-        return !operator==(other);
-    }
-
     constexpr bool
     operator<(ValueUnit const& other) const
     {

include/xrpl/protocol/detail/STVar.h

@@ -152,10 +152,4 @@ operator==(STVar const& lhs, STVar const& rhs)
     return lhs.get().isEquivalent(rhs.get());
 }
 
-inline bool
-operator!=(STVar const& lhs, STVar const& rhs)
-{
-    return !(lhs == rhs);
-}
-
 }  // namespace xrpl::detail

include/xrpl/protocol/detail/ledger_entries.macro

@@ -506,6 +506,9 @@ LEDGER_ENTRY(ltVAULT, 0x0084, Vault, vault, ({
     {sfWithdrawalPolicy,     SoeRequired},
     {sfScale,                SoeDefault},
     {sfLEVersion,            SoeDefault},
+    {sfVaultKind,            SoeDefault},
+    {sfSubscriptionDate,     SoeOptional},
+    {sfRedemptionDate,       SoeOptional},
     // no SharesTotal ever (use MPTIssuance.sfOutstandingAmount)
     // no PermissionedDomainID ever (use MPTIssuance.sfDomainID)
 }))

include/xrpl/protocol/detail/sfields.macro

@@ -23,9 +23,11 @@ TYPED_SFIELD(sfLEVersion,                UINT8,      6)
 // 8-bit integers (uncommon)
 TYPED_SFIELD(sfTickSize,                 UINT8,     16)
 TYPED_SFIELD(sfUNLModifyDisabling,       UINT8,     17)
-TYPED_SFIELD(sfHookResult,               UINT8,     18)
+// 18 unused
 TYPED_SFIELD(sfWasLockingChainSend,      UINT8,     19)
 TYPED_SFIELD(sfWithdrawalPolicy,         UINT8,     20)
+TYPED_SFIELD(sfContractResult,           UINT8,     21)
+TYPED_SFIELD(sfVaultKind,                UINT8,     22)
 
 // 16-bit integers (common)
 TYPED_SFIELD(sfLedgerEntryType,          UINT16,     1, SField::kSmdNever)
@@ -37,10 +39,7 @@ TYPED_SFIELD(sfDiscountedFee,            UINT16,     6)
 
 // 16-bit integers (uncommon)
 TYPED_SFIELD(sfVersion,                  UINT16,    16)
-TYPED_SFIELD(sfHookStateChangeCount,     UINT16,    17)
-TYPED_SFIELD(sfHookEmitCount,            UINT16,    18)
-TYPED_SFIELD(sfHookExecutionIndex,       UINT16,    19)
-TYPED_SFIELD(sfHookApiVersion,           UINT16,    20)
+// 17 to 20 unused
 TYPED_SFIELD(sfLedgerFixType,            UINT16,    21)
 TYPED_SFIELD(sfManagementFeeRate,        UINT16,    22) // 1/10 basis points (bips)
 
@@ -91,9 +90,7 @@ TYPED_SFIELD(sfTicketSequence,           UINT32,    41)
 TYPED_SFIELD(sfNFTokenTaxon,             UINT32,    42)
 TYPED_SFIELD(sfMintedNFTokens,           UINT32,    43)
 TYPED_SFIELD(sfBurnedNFTokens,           UINT32,    44)
-TYPED_SFIELD(sfHookStateCount,           UINT32,    45)
-TYPED_SFIELD(sfEmitGeneration,           UINT32,    46)
-//                                                  47 reserved for Hooks
+// 45 to 47 unused
 TYPED_SFIELD(sfVoteWeight,               UINT32,    48)
 TYPED_SFIELD(sfFirstNFTokenSequence,     UINT32,    50)
 TYPED_SFIELD(sfOracleDocumentID,         UINT32,    51)
@@ -120,6 +117,8 @@ TYPED_SFIELD(sfSponsoringOwnerCount,     UINT32,    71)
 TYPED_SFIELD(sfSponsoringAccountCount,   UINT32,    72)
 TYPED_SFIELD(sfRemainingOwnerCount,      UINT32,    73)
 TYPED_SFIELD(sfSponsorFlags,             UINT32,    74)
+TYPED_SFIELD(sfSubscriptionDate,         UINT32,    75)
+TYPED_SFIELD(sfRedemptionDate,           UINT32,    76)
 
 // 64-bit integers (common)
 TYPED_SFIELD(sfIndexNext,                UINT64,     1)
@@ -137,9 +136,7 @@ TYPED_SFIELD(sfNFTokenOfferNode,         UINT64,    12)
 TYPED_SFIELD(sfEmitBurden,               UINT64,    13)
 
 // 64-bit integers (uncommon)
-TYPED_SFIELD(sfHookOn,                   UINT64,    16)
-TYPED_SFIELD(sfHookInstructionCount,     UINT64,    17)
-TYPED_SFIELD(sfHookReturnCode,           UINT64,    18)
+// 16 to 18 unused
 TYPED_SFIELD(sfReferenceCount,           UINT64,    19)
 TYPED_SFIELD(sfXChainClaimID,            UINT64,    20)
 TYPED_SFIELD(sfXChainAccountCreateCount, UINT64,    21)
@@ -203,10 +200,7 @@ TYPED_SFIELD(sfPreviousPageMin,          UINT256,   26)
 TYPED_SFIELD(sfNextPageMin,              UINT256,   27)
 TYPED_SFIELD(sfNFTokenBuyOffer,          UINT256,   28)
 TYPED_SFIELD(sfNFTokenSellOffer,         UINT256,   29)
-TYPED_SFIELD(sfHookStateKey,             UINT256,   30)
-TYPED_SFIELD(sfHookHash,                 UINT256,   31)
-TYPED_SFIELD(sfHookNamespace,            UINT256,   32)
-TYPED_SFIELD(sfHookSetTxnID,             UINT256,   33)
+// 30 to 33 unused
 TYPED_SFIELD(sfDomainID,                 UINT256,   34)
 TYPED_SFIELD(sfVaultID,                  UINT256,   35,
     SField::kSmdPseudoAccount | SField::kSmdDefault)
@@ -237,7 +231,7 @@ TYPED_SFIELD(sfTotalValueOutstanding,    NUMBER,     15, SField::kSmdNeedsAsset
 TYPED_SFIELD(sfPeriodicPayment,          NUMBER,     16)
 TYPED_SFIELD(sfManagementFeeOutstanding, NUMBER,     17, SField::kSmdNeedsAsset | SField::kSmdDefault)
 
-// int32
+// 32-bit signed (common)
 TYPED_SFIELD(sfLoanScale,                INT32,      1)
 TYPED_SFIELD(sfRemainingOwnerCountDelta, INT32,      2)
 
@@ -261,15 +255,13 @@ TYPED_SFIELD(sfMinimumOffer,             AMOUNT,    16)
 TYPED_SFIELD(sfRippleEscrow,             AMOUNT,    17)
 TYPED_SFIELD(sfDeliveredAmount,          AMOUNT,    18)
 TYPED_SFIELD(sfNFTokenBrokerFee,         AMOUNT,    19)
-
-// Reserve 20 & 21 for Hooks.
-
+// 20 to 21 unused
 // currency amount (fees)
 TYPED_SFIELD(sfBaseFeeDrops,             AMOUNT,    22)
 TYPED_SFIELD(sfReserveBaseDrops,         AMOUNT,    23)
 TYPED_SFIELD(sfReserveIncrementDrops,    AMOUNT,    24)
 
-// currency amount (AMM)
+// currency amount (more)
 TYPED_SFIELD(sfLPTokenOut,               AMOUNT,    25)
 TYPED_SFIELD(sfLPTokenIn,                AMOUNT,    26)
 TYPED_SFIELD(sfEPrice,                   AMOUNT,    27)
@@ -304,10 +296,7 @@ TYPED_SFIELD(sfMasterSignature,          VL,        18, SField::kSmdDefault, SFi
 TYPED_SFIELD(sfUNLModifyValidator,       VL,        19)
 TYPED_SFIELD(sfValidatorToDisable,       VL,        20)
 TYPED_SFIELD(sfValidatorToReEnable,      VL,        21)
-TYPED_SFIELD(sfHookStateData,            VL,        22)
-TYPED_SFIELD(sfHookReturnString,         VL,        23)
-TYPED_SFIELD(sfHookParameterName,        VL,        24)
-TYPED_SFIELD(sfHookParameterValue,       VL,        25)
+// 22 to 25 unused
 TYPED_SFIELD(sfDIDDocument,              VL,        26)
 TYPED_SFIELD(sfData,                     VL,        27)
 TYPED_SFIELD(sfAssetClass,               VL,        28)
@@ -345,7 +334,7 @@ TYPED_SFIELD(sfHolder,                   ACCOUNT,   11)
 TYPED_SFIELD(sfDelegate,                 ACCOUNT,   12)
 
 // account (uncommon)
-TYPED_SFIELD(sfHookAccount,              ACCOUNT,   16)
+// 16 unused
 TYPED_SFIELD(sfOtherChainSource,         ACCOUNT,   18)
 TYPED_SFIELD(sfOtherChainDestination,    ACCOUNT,   19)
 TYPED_SFIELD(sfAttestationSignerAccount, ACCOUNT,   20)
@@ -398,7 +387,7 @@ UNTYPED_SFIELD(sfMemo,                   OBJECT,    10)
 UNTYPED_SFIELD(sfSignerEntry,            OBJECT,    11)
 UNTYPED_SFIELD(sfNFToken,                OBJECT,    12)
 UNTYPED_SFIELD(sfEmitDetails,            OBJECT,    13)
-UNTYPED_SFIELD(sfHook,                   OBJECT,    14)
+// 14 unused
 UNTYPED_SFIELD(sfPermission,             OBJECT,    15)
 
 // inner object (uncommon)
@@ -406,11 +395,7 @@ UNTYPED_SFIELD(sfSigner,                 OBJECT,    16)
 //                                                  17 unused
 UNTYPED_SFIELD(sfMajority,               OBJECT,    18)
 UNTYPED_SFIELD(sfDisabledValidator,      OBJECT,    19)
-UNTYPED_SFIELD(sfEmittedTxn,             OBJECT,    20)
-UNTYPED_SFIELD(sfHookExecution,          OBJECT,    21)
-UNTYPED_SFIELD(sfHookDefinition,         OBJECT,    22)
-UNTYPED_SFIELD(sfHookParameter,          OBJECT,    23)
-UNTYPED_SFIELD(sfHookGrant,              OBJECT,    24)
+// 20 to 24 unused
 UNTYPED_SFIELD(sfVoteEntry,              OBJECT,    25)
 UNTYPED_SFIELD(sfAuctionSlot,            OBJECT,    26)
 UNTYPED_SFIELD(sfAuthAccount,            OBJECT,    27)
@@ -438,16 +423,14 @@ UNTYPED_SFIELD(sfSufficient,             ARRAY,      7)
 UNTYPED_SFIELD(sfAffectedNodes,          ARRAY,      8)
 UNTYPED_SFIELD(sfMemos,                  ARRAY,      9)
 UNTYPED_SFIELD(sfNFTokens,               ARRAY,     10)
-UNTYPED_SFIELD(sfHooks,                  ARRAY,     11)
+// 11 unused
 UNTYPED_SFIELD(sfVoteSlots,              ARRAY,     12)
 UNTYPED_SFIELD(sfAdditionalBooks,        ARRAY,     13)
 
 // array of objects (uncommon)
 UNTYPED_SFIELD(sfMajorities,             ARRAY,     16)
 UNTYPED_SFIELD(sfDisabledValidators,     ARRAY,     17)
-UNTYPED_SFIELD(sfHookExecutions,         ARRAY,     18)
-UNTYPED_SFIELD(sfHookParameters,         ARRAY,     19)
-UNTYPED_SFIELD(sfHookGrants,             ARRAY,     20)
+// 18 to 20 unused
 UNTYPED_SFIELD(sfXChainClaimAttestations, ARRAY,    21)
 UNTYPED_SFIELD(sfXChainCreateAccountAttestations, ARRAY, 22)
 //                                                  23 unused

include/xrpl/protocol/detail/transactions.macro

@@ -862,6 +862,9 @@ TRANSACTION(ttVAULT_CREATE, 65, VaultCreate,
     {sfWithdrawalPolicy, SoeOptional},
     {sfData, SoeOptional},
     {sfScale, SoeOptional},
+    {sfVaultKind, SoeOptional},
+    {sfSubscriptionDate, SoeOptional},
+    {sfRedemptionDate, SoeOptional},
 }))
 
 /** This transaction updates a single asset vault. */

include/xrpl/protocol_autogen/ledger_entries/Vault.h

@@ -311,6 +311,78 @@ public:
     {
         return this->sle_->isFieldPresent(sfLEVersion);
     }
+
+    /**
+     * @brief Get sfVaultKind (SoeDefault)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT8::type::value_type>
+    getVaultKind() const
+    {
+        if (hasVaultKind())
+            return this->sle_->at(sfVaultKind);
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfVaultKind is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasVaultKind() const
+    {
+        return this->sle_->isFieldPresent(sfVaultKind);
+    }
+
+    /**
+     * @brief Get sfSubscriptionDate (SoeOptional)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT32::type::value_type>
+    getSubscriptionDate() const
+    {
+        if (hasSubscriptionDate())
+            return this->sle_->at(sfSubscriptionDate);
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfSubscriptionDate is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasSubscriptionDate() const
+    {
+        return this->sle_->isFieldPresent(sfSubscriptionDate);
+    }
+
+    /**
+     * @brief Get sfRedemptionDate (SoeOptional)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT32::type::value_type>
+    getRedemptionDate() const
+    {
+        if (hasRedemptionDate())
+            return this->sle_->at(sfRedemptionDate);
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfRedemptionDate is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasRedemptionDate() const
+    {
+        return this->sle_->isFieldPresent(sfRedemptionDate);
+    }
 };
 
 /**
@@ -543,6 +615,39 @@ public:
         return *this;
     }
 
+    /**
+     * @brief Set sfVaultKind (SoeDefault)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultBuilder&
+    setVaultKind(std::decay_t<typename SF_UINT8::type::value_type> const& value)
+    {
+        object_[sfVaultKind] = value;
+        return *this;
+    }
+
+    /**
+     * @brief Set sfSubscriptionDate (SoeOptional)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultBuilder&
+    setSubscriptionDate(std::decay_t<typename SF_UINT32::type::value_type> const& value)
+    {
+        object_[sfSubscriptionDate] = value;
+        return *this;
+    }
+
+    /**
+     * @brief Set sfRedemptionDate (SoeOptional)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultBuilder&
+    setRedemptionDate(std::decay_t<typename SF_UINT32::type::value_type> const& value)
+    {
+        object_[sfRedemptionDate] = value;
+        return *this;
+    }
+
     /**
      * @brief Build and return the completed Vault wrapper.
      * @param index The ledger entry index.

include/xrpl/protocol_autogen/transactions/VaultCreate.h

@@ -214,6 +214,84 @@ public:
     {
         return this->tx_->isFieldPresent(sfScale);
     }
+
+    /**
+     * @brief Get sfVaultKind (SoeOptional)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT8::type::value_type>
+    getVaultKind() const
+    {
+        if (hasVaultKind())
+        {
+            return this->tx_->at(sfVaultKind);
+        }
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfVaultKind is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasVaultKind() const
+    {
+        return this->tx_->isFieldPresent(sfVaultKind);
+    }
+
+    /**
+     * @brief Get sfSubscriptionDate (SoeOptional)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT32::type::value_type>
+    getSubscriptionDate() const
+    {
+        if (hasSubscriptionDate())
+        {
+            return this->tx_->at(sfSubscriptionDate);
+        }
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfSubscriptionDate is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasSubscriptionDate() const
+    {
+        return this->tx_->isFieldPresent(sfSubscriptionDate);
+    }
+
+    /**
+     * @brief Get sfRedemptionDate (SoeOptional)
+     * @return The field value, or std::nullopt if not present.
+     */
+    [[nodiscard]]
+    protocol_autogen::Optional<SF_UINT32::type::value_type>
+    getRedemptionDate() const
+    {
+        if (hasRedemptionDate())
+        {
+            return this->tx_->at(sfRedemptionDate);
+        }
+        return std::nullopt;
+    }
+
+    /**
+     * @brief Check if sfRedemptionDate is present.
+     * @return True if the field is present, false otherwise.
+     */
+    [[nodiscard]]
+    bool
+    hasRedemptionDate() const
+    {
+        return this->tx_->isFieldPresent(sfRedemptionDate);
+    }
 };
 
 /**
@@ -338,6 +416,39 @@ public:
         return *this;
     }
 
+    /**
+     * @brief Set sfVaultKind (SoeOptional)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultCreateBuilder&
+    setVaultKind(std::decay_t<typename SF_UINT8::type::value_type> const& value)
+    {
+        object_[sfVaultKind] = value;
+        return *this;
+    }
+
+    /**
+     * @brief Set sfSubscriptionDate (SoeOptional)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultCreateBuilder&
+    setSubscriptionDate(std::decay_t<typename SF_UINT32::type::value_type> const& value)
+    {
+        object_[sfSubscriptionDate] = value;
+        return *this;
+    }
+
+    /**
+     * @brief Set sfRedemptionDate (SoeOptional)
+     * @return Reference to this builder for method chaining.
+     */
+    VaultCreateBuilder&
+    setRedemptionDate(std::decay_t<typename SF_UINT32::type::value_type> const& value)
+    {
+        object_[sfRedemptionDate] = value;
+        return *this;
+    }
+
     /**
      * @brief Build and return the VaultCreate wrapper.
      * @param publicKey The public key for signing.

include/xrpl/rdb/DBInit.h

@@ -2,6 +2,9 @@
 
 #include <array>
 #include <cstdint>
+#include <format>
+#include <string>
+#include <string_view>
 
 namespace xrpl {
 
@@ -9,9 +12,29 @@ namespace xrpl {
 
 // These pragmas are built at startup and applied to all database
 // connections, unless otherwise noted.
-inline constexpr char const* kCommonDbPragmaJournal{"PRAGMA journal_mode=%s;"};
-inline constexpr char const* kCommonDbPragmaSync{"PRAGMA synchronous=%s;"};
-inline constexpr char const* kCommonDbPragmaTemp{"PRAGMA temp_store=%s;"};
+//
+// They are exposed as functions rather than as format-string constants so
+// that the un-substituted template can never reach sqlite: an unrecognized
+// pragma value is silently ignored, so forgetting to interpolate would
+// leave the setting at its default instead of failing loudly.
+[[nodiscard]] inline std::string
+commonDbPragmaJournal(std::string_view journalMode)
+{
+    return std::format("PRAGMA journal_mode={};", journalMode);
+}
+
+[[nodiscard]] inline std::string
+commonDbPragmaSync(std::string_view synchronous)
+{
+    return std::format("PRAGMA synchronous={};", synchronous);
+}
+
+[[nodiscard]] inline std::string
+commonDbPragmaTemp(std::string_view tempStore)
+{
+    return std::format("PRAGMA temp_store={};", tempStore);
+}
+
 // A warning will be logged if any lower-safety sqlite tuning settings
 // are used and at least this much ledger history is configured. This
 // includes full history nodes. This is because such a large amount of

include/xrpl/rdb/DatabaseCon.h

@@ -6,13 +6,12 @@
 #include <xrpl/core/StartUpType.h>
 #include <xrpl/rdb/SociDB.h>
 
-#include <boost/filesystem/path.hpp>
-
 #include <soci/statement.h>
 
 #include <array>
 #include <cstddef>
 #include <cstdint>
+#include <filesystem>
 #include <functional>
 #include <memory>
 #include <mutex>
@@ -80,7 +79,7 @@ public:
 
         StartUpType startUp = StartUpType::Normal;
         bool standAlone = false;
-        boost::filesystem::path dataDir;
+        std::filesystem::path dataDir;
         // Indicates whether or not to return the `globalPragma`
         // from commonPragma()
         bool useGlobalPragma = false;
@@ -143,7 +142,7 @@ public:
 
     template <std::size_t N, std::size_t M>
     DatabaseCon(
-        boost::filesystem::path const& dataDir,
+        std::filesystem::path const& dataDir,
         std::string const& dbName,
         std::array<std::string, N> const& pragma,
         std::array<char const*, M> const& initSQL,
@@ -155,7 +154,7 @@ public:
     // Use this constructor to setup checkpointing
     template <std::size_t N, std::size_t M>
     DatabaseCon(
-        boost::filesystem::path const& dataDir,
+        std::filesystem::path const& dataDir,
         std::string const& dbName,
         std::array<std::string, N> const& pragma,
         std::array<char const*, M> const& initSQL,
@@ -190,7 +189,7 @@ private:
 
     template <std::size_t N, std::size_t M>
     DatabaseCon(
-        boost::filesystem::path const& pPath,
+        std::filesystem::path const& pPath,
         std::vector<std::string> const* commonPragma,
         std::array<std::string, N> const& pragma,
         std::array<char const*, M> const& initSQL,

include/xrpl/rdb/RelationalDatabase.h

@@ -14,7 +14,6 @@
 #include <xrpl/protocol/TxMeta.h>
 #include <xrpl/protocol/TxSearched.h>
 
-#include <boost/filesystem.hpp>
 #include <boost/variant.hpp>
 
 #include <concepts>

include/xrpl/server/Manifest.h

@@ -306,12 +306,6 @@ operator==(Manifest const& lhs, Manifest const& rhs)
         lhs.serialized == rhs.serialized;
 }
 
-inline bool
-operator!=(Manifest const& lhs, Manifest const& rhs)
-{
-    return !(lhs == rhs);
-}
-
 struct ValidatorToken
 {
     std::string manifest;

include/xrpl/server/State.h

@@ -4,8 +4,6 @@
 #include <xrpl/rdb/DatabaseCon.h>
 #include <xrpl/rdb/SociDB.h>
 
-#include <boost/filesystem.hpp>
-
 #include <string>
 
 namespace xrpl {

include/xrpl/server/Wallet.h

@@ -10,6 +10,10 @@
 #include <xrpl/rdb/DatabaseCon.h>
 #include <xrpl/server/Manifest.h>
 
+// boost::optional (not std::optional) appears in the declarations below,
+// because SOCI's into()/use() bindings only support boost::optional.
+#include <boost/optional/optional.hpp>
+
 #include <functional>
 #include <memory>
 #include <string>

include/xrpl/server/detail/BaseWSPeer.h

@@ -25,6 +25,7 @@
 #include <iterator>
 #include <list>
 #include <memory>
+#include <string_view>
 #include <utility>
 #include <vector>
 
@@ -62,8 +63,7 @@ private:
     bool pingActive_ = false;
     boost::beast::websocket::ping_data payload_;
     error_code ec_;
-    std::function<void(boost::beast::websocket::frame_type, boost::beast::string_view)>
-        controlCallback_;
+    std::function<void(boost::beast::websocket::frame_type, std::string_view)> controlCallback_;
 
 public:
     template <class Body, class Headers>
@@ -151,7 +151,7 @@ protected:
     onPing(error_code const& ec);
 
     void
-    onPingPong(boost::beast::websocket::frame_type kind, boost::beast::string_view payload);
+    onPingPong(boost::beast::websocket::frame_type kind, std::string_view payload);
 
     void
     onTimer(error_code ec);
@@ -189,9 +189,9 @@ BaseWSPeer<Handler, Impl>::run()
     impl().ws_.set_option(port().pmdOptions);
     // Must manage the control callback memory outside of the `control_callback`
     // function
-    controlCallback_ = [this](
-                           boost::beast::websocket::frame_type kind,
-                           boost::beast::string_view payload) { onPingPong(kind, payload); };
+    controlCallback_ = [this](boost::beast::websocket::frame_type kind, std::string_view payload) {
+        onPingPong(kind, payload);
+    };
     impl().ws_.control_callback(controlCallback_);
     startTimer();
     closeOnTimer_ = true;
@@ -430,11 +430,11 @@ template <class Handler, class Impl>
 void
 BaseWSPeer<Handler, Impl>::onPingPong(
     boost::beast::websocket::frame_type kind,
-    boost::beast::string_view payload)
+    std::string_view payload)
 {
     if (kind == boost::beast::websocket::frame_type::pong)
     {
-        boost::beast::string_view const p(payload_.begin());
+        std::string_view const p(payload_.begin(), payload_.size());
         if (payload == p)
         {
             closeOnTimer_ = false;

include/xrpl/shamap/SHAMap.h

@@ -484,31 +484,36 @@ private:
 
     // returns the first item at or below this node
     SHAMapLeafNode*
-    firstBelow(SHAMapTreeNodePtr node, SharedPtrNodeStack& stack, int branch = 0) const;
+    firstBelow(SHAMapTreeNodePtr node, SharedPtrNodeStack& stack, unsigned int branch = 0u) const;
 
     // returns the last item at or below this node
     SHAMapLeafNode*
-    lastBelow(SHAMapTreeNodePtr node, SharedPtrNodeStack& stack, int branch = kBranchFactor) const;
+    lastBelow(
+        SHAMapTreeNodePtr node,
+        SharedPtrNodeStack& stack,
+        unsigned int branch = kBranchFactor) const;
+
+    // direction in which belowHelper scans an inner node's branches
+    enum class BelowDirection { First, Last };
 
     // helper function for firstBelow and lastBelow
     SHAMapLeafNode*
     belowHelper(
         SHAMapTreeNodePtr node,
         SharedPtrNodeStack& stack,
-        int branch,
-        std::tuple<int, std::function<bool(int)>, std::function<void(int&)>> const& loopParams)
-        const;
+        unsigned int branch,
+        BelowDirection direction) const;
 
     // Simple descent
     // Get a child of the specified node
     SHAMapTreeNode*
-    descend(SHAMapInnerNode*, int branch) const;
+    descend(SHAMapInnerNode*, unsigned int branch) const;
     SHAMapTreeNode*
-    descendThrow(SHAMapInnerNode*, int branch) const;
+    descendThrow(SHAMapInnerNode*, unsigned int branch) const;
     SHAMapTreeNodePtr
-    descend(SHAMapInnerNode&, int branch) const;
+    descend(SHAMapInnerNode&, unsigned int branch) const;
     SHAMapTreeNodePtr
-    descendThrow(SHAMapInnerNode&, int branch) const;
+    descendThrow(SHAMapInnerNode&, unsigned int branch) const;
 
     // Descend with filter
     // If pending, callback is called as if it called fetchNodeNT
@@ -516,7 +521,7 @@ private:
     SHAMapTreeNode*
     descendAsync(
         SHAMapInnerNode* parent,
-        int branch,
+        unsigned int branch,
         SHAMapSyncFilter const* filter,
         bool& pending,
         descendCallback&&) const;
@@ -525,13 +530,13 @@ private:
     descend(
         SHAMapInnerNode* parent,
         SHAMapNodeID const& parentID,
-        int branch,
+        unsigned int branch,
         SHAMapSyncFilter const* filter) const;
 
     // Non-storing
     // Does not hook the returned node to its parent
     SHAMapTreeNodePtr
-    descendNoStore(SHAMapInnerNode&, int branch) const;
+    descendNoStore(SHAMapInnerNode&, unsigned int branch) const;
 
     /**
      * If there is only one leaf below this node, get its contents
@@ -581,8 +586,8 @@ private:
         using StackEntry = std::tuple<
             SHAMapInnerNode*,  // pointer to the node
             SHAMapNodeID,      // the node's ID
-            int,               // while child we check first
-            int,               // which child we check next
+            unsigned int,      // which child we check first
+            unsigned int,      // which child we check next
             bool>;             // whether we've found any missing children yet
 
         // We explicitly choose to specify the use of std::deque here, because
@@ -596,7 +601,7 @@ private:
         using DeferredNode = std::tuple<
             SHAMapInnerNode*,    // parent node
             SHAMapNodeID,        // parent node ID
-            int,                 // branch
+            unsigned int,        // branch
             SHAMapTreeNodePtr>;  // node
 
         int deferred;
@@ -789,12 +794,6 @@ operator==(SHAMap::ConstIterator const& x, SHAMap::ConstIterator const& y)
     return x.item_ == y.item_;
 }
 
-inline bool
-operator!=(SHAMap::ConstIterator const& x, SHAMap::ConstIterator const& y)
-{
-    return !(x == y);
-}
-
 inline SHAMap::ConstIterator
 SHAMap::begin() const
 {

include/xrpl/shamap/SHAMapInnerNode.h

@@ -62,8 +62,8 @@ private:
      *
      * @param i index of the requested child
      */
-    std::optional<int>
-    getChildIndex(int i) const;
+    std::optional<unsigned int>
+    getChildIndex(unsigned int i) const;
 
     /**
      * Call the `f` callback for all 16 (branchFactor) branches - even if
@@ -125,28 +125,28 @@ public:
     isEmpty() const;
 
     bool
-    isEmptyBranch(int m) const;
+    isEmptyBranch(unsigned int branch) const;
 
-    int
+    unsigned int
     getBranchCount() const;
 
     SHAMapHash const&
-    getChildHash(int m) const;
+    getChildHash(unsigned int branch) const;
 
     void
-    setChild(int m, SHAMapTreeNodePtr child);
+    setChild(unsigned int branch, SHAMapTreeNodePtr child);
 
     void
-    shareChild(int m, SHAMapTreeNodePtr const& child);
+    shareChild(unsigned int branch, SHAMapTreeNodePtr const& child);
 
     SHAMapTreeNode*
-    getChildPointer(int branch);
+    getChildPointer(unsigned int branch);
 
     SHAMapTreeNodePtr
-    getChild(int branch);
+    getChild(unsigned int branch);
 
     SHAMapTreeNodePtr
-    canonicalizeChild(int branch, SHAMapTreeNodePtr node);
+    canonicalizeChild(unsigned int branch, SHAMapTreeNodePtr node);
 
     // sync functions
     bool
@@ -190,12 +190,12 @@ SHAMapInnerNode::isEmpty() const
 }
 
 inline bool
-SHAMapInnerNode::isEmptyBranch(int m) const
+SHAMapInnerNode::isEmptyBranch(unsigned int branch) const
 {
-    return (isBranch_ & (1 << m)) == 0;
+    return (isBranch_ & (1u << branch)) == 0u;
 }
 
-inline int
+inline unsigned int
 SHAMapInnerNode::getBranchCount() const
 {
     return popcnt16(isBranch_);

include/xrpl/shamap/SHAMapNodeID.h

@@ -3,6 +3,7 @@
 #include <xrpl/basics/CountedObject.h>
 #include <xrpl/basics/base_uint.h>
 
+#include <compare>
 #include <cstddef>
 #include <optional>
 #include <ostream>
@@ -52,7 +53,7 @@ public:
     }
 
     [[nodiscard]] SHAMapNodeID
-    getChildNodeID(unsigned int m) const;
+    getChildNodeID(unsigned int branch) const;
 
     /**
      * Create a SHAMapNodeID of a node with the depth of the node and
@@ -63,47 +64,34 @@ public:
      * @return SHAMapNodeID of the node
      */
     static SHAMapNodeID
-    createID(int depth, uint256 const& key);
+    createID(unsigned int depth, uint256 const& key);
 
-    // FIXME-C++20: use spaceship and operator synthesis
     /**
      * Comparison operators
+     *
+     * <, >, <= and >= are synthesized from the spaceship. It is written out
+     * rather than defaulted because the ordering is by depth first, and the
+     * members are not declared in that order.
      */
-    bool
-    operator<(SHAMapNodeID const& n) const
+    std::strong_ordering
+    operator<=>(SHAMapNodeID const& n) const
     {
-        return std::tie(depth_, id_) < std::tie(n.depth_, n.id_);
-    }
-
-    bool
-    operator>(SHAMapNodeID const& n) const
-    {
-        return n < *this;
-    }
-
-    bool
-    operator<=(SHAMapNodeID const& n) const
-    {
-        return !(n < *this);
-    }
-
-    bool
-    operator>=(SHAMapNodeID const& n) const
-    {
-        return !(*this < n);
+        return std::tie(depth_, id_) <=> std::tie(n.depth_, n.id_);
     }
 
+    /**
+     * Equality, which the spaceship above does not provide.
+     *
+     * Only a *defaulted* operator<=> implicitly declares a defaulted
+     * operator==; the one above is user-provided, so == has to be written.
+     * It cannot be defaulted either, because a defaulted == would also compare
+     * the CountedObject base, which is not equality comparable.
+     */
     bool
     operator==(SHAMapNodeID const& n) const
     {
         return (depth_ == n.depth_) && (id_ == n.id_);
     }
-
-    bool
-    operator!=(SHAMapNodeID const& n) const
-    {
-        return !(*this == n);
-    }
 };
 
 inline std::string

include/xrpl/shamap/detail/TaggedPointer.h

@@ -219,11 +219,11 @@ public:
      *
      * @param i index of the requested child
      */
-    [[nodiscard]] std::optional<int>
-    getChildIndex(std::uint16_t isBranch, int i) const;
+    [[nodiscard]] std::optional<unsigned int>
+    getChildIndex(std::uint16_t isBranch, unsigned int i) const;
 };
 
-[[nodiscard]] inline int
+[[nodiscard]] inline unsigned int
 popcnt16(std::uint16_t a)
 {
 #if __cpp_lib_bitops
@@ -234,11 +234,11 @@ popcnt16(std::uint16_t a)
     // fallback to table lookup
     static constexpr auto tbl = []() {
         std::array<std::uint8_t, 256> ret{};
-        for (int i = 0; i != 256; ++i)
+        for (auto i = 0u; i != 256u; ++i)
         {
-            for (int j = 0; j != 8; ++j)
+            for (auto j = 0u; j != 8u; ++j)
             {
-                if (i & (1 << j))
+                if (i & (1u << j))
                     ret[i]++;
             }
         }

include/xrpl/shamap/detail/TaggedPointer.ipp

@@ -22,6 +22,11 @@ static_assert(
 static_assert(
     kBoundaries.back() == SHAMapInnerNode::kBranchFactor,
     "Last element of boundaries must be number of children in a dense array");
+static_assert(
+    kBoundaries.front() >= 1,
+    "TaggedPointer.ipp subtracts 1 from a numAllocated value derived from "
+    "kBoundaries, as an unsigned quantity, in several places; the smallest "
+    "boundary must stay non-zero or those subtractions underflow.");
 
 // Terminology: A chunk is the memory being allocated from a block. A block
 // contains multiple chunks. This is the terminology the boost documentation
@@ -148,16 +153,16 @@ TaggedPointer::iterChildren(std::uint16_t isBranch, F&& f) const
     if (numAllocated == SHAMapInnerNode::kBranchFactor)
     {
         // dense case
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
             f(hashes[i]);
     }
     else
     {
         // sparse case
-        int curHashI = 0;
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        auto curHashI = 0u;
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            if ((1 << i) & isBranch)
+            if ((1u << i) & isBranch)
             {
                 f(hashes[curHashI++]);
             }
@@ -176,9 +181,9 @@ TaggedPointer::iterNonEmptyChildIndexes(std::uint16_t isBranch, F&& f) const
     if (capacity() == SHAMapInnerNode::kBranchFactor)
     {
         // dense case
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            if ((1 << i) & isBranch)
+            if ((1u << i) & isBranch)
             {
                 f(i, i);
             }
@@ -187,10 +192,10 @@ TaggedPointer::iterNonEmptyChildIndexes(std::uint16_t isBranch, F&& f) const
     else
     {
         // sparse case
-        int curHashI = 0;
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        auto curHashI = 0u;
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            if ((1 << i) & isBranch)
+            if ((1u << i) & isBranch)
             {
                 f(i, curHashI++);
             }
@@ -216,14 +221,14 @@ TaggedPointer::destroyHashesAndChildren()
     deallocateArrays(tag, ptr);
 }
 
-inline std::optional<int>
-TaggedPointer::getChildIndex(std::uint16_t isBranch, int i) const
+inline std::optional<unsigned int>
+TaggedPointer::getChildIndex(std::uint16_t isBranch, unsigned int i) const
 {
     if (isDense())
         return i;
 
     // Sparse case
-    if ((isBranch & (1 << i)) == 0)
+    if ((isBranch & (1u << i)) == 0u)
     {
         // Empty branch. Sparse children do not store empty branches
         return {};
@@ -273,10 +278,10 @@ inline TaggedPointer::TaggedPointer(
         *this = std::move(other);
         auto [srcDstNumAllocated, srcDstHashes, srcDstChildren] = getHashesAndChildren();
         bool const srcDstIsDense = isDense();
-        int srcDstIndex = 0;
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        auto srcDstIndex = 0u;
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            auto const mask = (1 << i);
+            auto const mask = (1u << i);
             bool const inSrc = (srcBranches & mask) != 0;
             bool const inDst = (dstBranches & mask) != 0;
             if (inSrc && inDst)
@@ -298,13 +303,13 @@ inline TaggedPointer::TaggedPointer(
                     // sparse
                     // need to shift all the elements to the left by
                     // one
-                    for (int c = srcDstIndex; c < srcDstNumAllocated - 1; ++c)
+                    for (auto c = srcDstIndex; c + 1 < srcDstNumAllocated; ++c)
                     {
                         srcDstHashes[c] = srcDstHashes[c + 1];
                         srcDstChildren[c] = std::move(srcDstChildren[c + 1]);
                     }
-                    srcDstHashes[srcDstNumAllocated - 1].zero();
-                    srcDstChildren[srcDstNumAllocated - 1].reset();
+                    srcDstHashes[srcDstNumAllocated - 1u].zero();
+                    srcDstChildren[srcDstNumAllocated - 1u].reset();
                     // do not increment the index
                 }
             }
@@ -321,7 +326,7 @@ inline TaggedPointer::TaggedPointer(
                     // sparse
                     // need to create a hole by shifting all the elements to the
                     // right by one
-                    for (int c = srcDstNumAllocated - 1; c > srcDstIndex; --c)
+                    for (auto c = srcDstNumAllocated - 1u; c > srcDstIndex; --c)
                     {
                         srcDstHashes[c] = srcDstHashes[c - 1];
                         srcDstChildren[c] = std::move(srcDstChildren[c - 1]);
@@ -352,10 +357,10 @@ inline TaggedPointer::TaggedPointer(
         auto [srcNumAllocated, srcHashes, srcChildren] = src.getHashesAndChildren();
         bool const srcIsDense = src.isDense();
         bool const dstIsDense = dst.isDense();
-        int srcIndex = 0, dstIndex = 0;
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        auto srcIndex = 0u, dstIndex = 0u;
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            auto const mask = (1 << i);
+            auto const mask = (1u << i);
             bool const inSrc = (srcBranches & mask) != 0;
             bool const inDst = (dstBranches & mask) != 0;
             if (inSrc && inDst)
@@ -409,7 +414,7 @@ inline TaggedPointer::TaggedPointer(
             !dstIsDense || dstIndex == dstNumAllocated,
             "xrpl::TaggedPointer::TaggedPointer(TaggedPointer&& ...) : "
             "non-sparse or valid sparse");
-        for (int i = dstIndex; i < dstNumAllocated; ++i)
+        for (auto i = dstIndex; i < dstNumAllocated; ++i)
         {
             new (&dstHashes[i]) SHAMapHash{};
             new (&dstChildren[i]) SHAMapTreeNodePtr{};
@@ -448,9 +453,9 @@ inline TaggedPointer::TaggedPointer(
             new (&newChildren[branchNum]) SHAMapTreeNodePtr{std::move(oldChildren[indexNum])};
         });
         // Run the constructors for the remaining elements
-        for (int i = 0; i < SHAMapInnerNode::kBranchFactor; ++i)
+        for (auto i = 0u; i < SHAMapInnerNode::kBranchFactor; ++i)
         {
-            if (((1 << i) & isBranch) != 0)
+            if (((1u << i) & isBranch) != 0u)
                 continue;
             new (&newHashes[i]) SHAMapHash{};
             new (&newChildren[i]) SHAMapTreeNodePtr{};
@@ -459,7 +464,7 @@ inline TaggedPointer::TaggedPointer(
     else
     {
         // new arrays are sparse, old arrays may be sparse or dense
-        int curCompressedIndex = 0;
+        auto curCompressedIndex = 0u;
         iterNonEmptyChildIndexes(isBranch, [&](auto branchNum, auto indexNum) {
             new (&newHashes[curCompressedIndex]) SHAMapHash{oldHashes[indexNum]};
             new (&newChildren[curCompressedIndex])
@@ -467,7 +472,7 @@ inline TaggedPointer::TaggedPointer(
             ++curCompressedIndex;
         });
         // Run the constructors for the remaining elements
-        for (int i = curCompressedIndex; i < newNumAllocated; ++i)
+        for (auto i = curCompressedIndex; i < newNumAllocated; ++i)
         {
             new (&newHashes[i]) SHAMapHash{};
             new (&newChildren[i]) SHAMapTreeNodePtr{};

include/xrpl/tx/invariants/FreezeInvariant.h

@@ -69,7 +69,8 @@ private:
         IssuerChanges const& changes,
         STTx const& tx,
         beast::Journal const& j,
-        bool enforce);
+        bool enforce,
+        bool fixOverrideFreeze);
 
     static bool
     validateFrozenState(
@@ -78,7 +79,8 @@ private:
         STTx const& tx,
         beast::Journal const& j,
         bool enforce,
-        bool globalFreeze);
+        bool globalFreeze,
+        bool fixOverrideFreeze);
 };
 
 }  // namespace xrpl

include/xrpl/tx/invariants/InvariantCheck.h

@@ -198,7 +198,7 @@ public:
 
 /**
  * @brief Invariant: An account XRP balance must be in XRP and take a value
- *                   between 0 and INITIAL_XRP drops, inclusive.
+ *                   between 0 and kInitialXRP drops, inclusive.
  *
  * We iterate all account roots modified by the transaction and ensure that
  * their XRP balances are reasonable.
@@ -290,7 +290,7 @@ public:
 
 /**
  * @brief Invariant: an escrow entry must take a value between 0 and
- *                   INITIAL_XRP drops exclusive.
+ *                   kInitialXRP drops exclusive.
  */
 class NoZeroEscrow
 {

include/xrpl/tx/invariants/LoanInvariant.h

@@ -16,6 +16,8 @@ namespace xrpl {
  * @brief Invariants: Loans are internally consistent
  *
  * 1. If `Loan.PaymentRemaining = 0` then `Loan.PrincipalOutstanding = 0`
+ * 2. A newly-created Loan against a closed-ended vault must satisfy
+ *    `StartDate + PaymentInterval * PaymentRemaining < Vault.RedemptionDate`.
  *
  */
 class ValidLoan

include/xrpl/tx/invariants/VaultInvariant.h

@@ -38,7 +38,17 @@ namespace xrpl {
  * - vault set must not alter the vault assets or shares balance
  * - no vault transaction can change loss unrealized (it's updated by loan
  *   transactions)
+ * - a created closed-ended vault must satisfy
+ *   MIN_INVESTMENT_PERIOD <= RedemptionDate - SubscriptionDate <
+ *   MAX_INVESTMENT_PERIOD
+ * - vault deposit may only succeed when the vault phase is NoPhase or
+ *   Subscription
+ * - vault withdrawal may not succeed when the vault phase is Investment
+ * - closed-ended loan origination (ttLOAN_SET) may only succeed when the
+ *   vault phase is Investment
  *
+ * Immutability of VaultKind, SubscriptionDate and RedemptionDate is enforced
+ * by NoModifiedUnmodifiableFields (see InvariantCheck.cpp).
  */
 class ValidVault
 {
@@ -55,6 +65,9 @@ class ValidVault
         Number assetsAvailable = 0;
         Number assetsMaximum = 0;
         Number lossUnrealized = 0;
+        std::optional<std::uint8_t> vaultKind;
+        std::optional<std::uint32_t> subscriptionDate;
+        std::optional<std::uint32_t> redemptionDate;
 
         Vault static make(SLE const&);
     };
@@ -153,6 +166,17 @@ private:
     [[nodiscard]] static bool
     isVaultEmpty(Vault const& vault);
 
+    /**
+     * @brief Invariant check for @c ttLOAN_SET.
+     *
+     * For a closed-ended vault, a loan may only be originated while the vault is in the Investment
+     * phase (strictly past @c SubscriptionDate and before @c RedemptionDate). Open-ended vaults (@c
+     * NoPhase) are unaffected. The complementary maturity bound (final payment strictly precedes @c
+     * RedemptionDate) is enforced by @c ValidLoan.
+     */
+    [[nodiscard]] bool
+    finalizeLoanSet(ReadView const& view, beast::Journal const& j) const;
+
 public:
     // Compute the coarsest scale required to represent all numbers
     [[nodiscard]] static std::int32_t

include/xrpl/tx/paths/detail/Steps.h

@@ -274,19 +274,6 @@ public:
         return lhs.equal(rhs);
     }
 
-    /**
-     * Return true if lhs != rhs.
-     *
-     * @param lhs Step to compare.
-     * @param rhs Step to compare.
-     * @return true if lhs != rhs.
-     */
-    friend bool
-    operator!=(Step const& lhs, Step const& rhs)
-    {
-        return !(lhs == rhs);
-    }
-
     /**
      * Streaming operator for a Step.
      */

include/xrpl/tx/paths/detail/StrandFlow.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <xrpl/basics/Log.h>
+#include <xrpl/basics/Number.h>
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/beast/utility/Zero.h>
@@ -373,7 +374,7 @@ qualityUpperBound(ReadView const& v, Strand const& strand)
  * increases quality of AMM steps, increasing the strand's composite
  * quality as the result.
  */
-template <typename TOutAmt>
+template <StepAmount TOutAmt>
 inline TOutAmt
 limitOut(
     ReadView const& v,
@@ -411,21 +412,29 @@ limitOut(
         auto const out = qf->outFromAvgQ(limitQuality);
         if (!out)
             return remainingOut;
-        if constexpr (std::is_same_v<TOutAmt, XRPAmount>)
+        if constexpr (std::is_same_v<TOutAmt, XRPAmount> || std::is_same_v<TOutAmt, MPTAmount>)
         {
-            return XRPAmount{*out};
+            auto const roundedOut = TOutAmt{*out};
+            // Integral outputs that round above the continuous target can
+            // realize worse average quality than the requested limit. Keep the
+            // default rounded value when it still satisfies the limit, since it
+            // is the largest matching offer; otherwise round down.
+            if (v.rules().enabled(featureMPTokensV2) && roundedOut > *out &&
+                !qf->satisfiesAvgQ(limitQuality, roundedOut))
+            {
+                NumberRoundModeGuard const g(Number::RoundingMode::Downward);
+                return TOutAmt{*out};
+            }
+            return roundedOut;
         }
         else if constexpr (std::is_same_v<TOutAmt, IOUAmount>)
         {
             return IOUAmount{*out};
         }
-        else if constexpr (std::is_same_v<TOutAmt, MPTAmount>)
-        {
-            return MPTAmount{*out};
-        }
         else
         {
-            return STAmount{remainingOut.asset(), out->mantissa(), out->exponent()};
+            static constexpr bool kAlwaysFalse = !std::is_same_v<TOutAmt, TOutAmt>;
+            static_assert(kAlwaysFalse, "Unhandled StepAmount type");
         }
     }();
     // A tiny difference could be due to the round off

include/xrpl/tx/transactors/dex/AMMWithdraw.h

@@ -118,6 +118,7 @@ public:
         Sandbox& view,
         SLE const& ammSle,
         AccountID const account,
+        std::optional<AccountID> const& clawbackIssuer,
         AccountID const& ammAccount,
         STAmount const& amountBalance,
         STAmount const& amount2Balance,
@@ -138,6 +139,11 @@ public:
      * @param view
      * @param ammSle AMM ledger entry
      * @param ammAccount AMM account
+     * @param clawbackIssuer when set (AMMClawback path), the issuer performing
+     *        the clawback. A recreated MPToken is only auto-authorized when the
+     *        asset's issuer matches this account, so a clawback cannot grant
+     *        authorization on behalf of a different (paired-asset) issuer.
+     * @param account LP account
      * @param amountBalance current LP asset1 balance
      * @param amountWithdraw asset1 withdraw amount
      * @param amount2Withdraw asset2 withdraw amount
@@ -153,6 +159,7 @@ public:
         Sandbox& view,
         SLE const& ammSle,
         AccountID const& ammAccount,
+        std::optional<AccountID> const& clawbackIssuer,
         AccountID const& account,
         STAmount const& amountBalance,
         STAmount const& amountWithdraw,

nix/check-tools/README.md

@@ -1,7 +1,8 @@
 # check-tools snapshots
 
 These files capture the output of [`bin/check-tools.sh`](../../bin/check-tools.sh)
-— the versions of the development tooling — in each Nix environment:
+— the version and resolved store path of each development tool — in each Nix
+environment:
 
 | File                   | Environment                          |
 | ---------------------- | ------------------------------------ |
@@ -17,9 +18,13 @@ So if you change the environment (bump the image tag in
 and commit the affected snapshots.
 
 Each snapshot is `check-tools.sh` stdout with the git-clone connectivity check
-skipped (`CHECK_TOOLS_SKIP_CLONE=1`), so it contains only deterministic version
-data. On macOS the dev-shell greeting that `nix develop` prints first is dropped
-with `sed -n '/^Detected OS:/,$p'`.
+skipped (`CHECK_TOOLS_SKIP_CLONE=1`), so it is deterministic for a given
+environment. On macOS the dev-shell greeting that `nix develop` prints first is
+dropped with `sed -n '/^Detected OS:/,$p'`.
+
+The store paths carry their derivation hash, so they change whenever a tool is
+rebuilt — a `flake.lock` update generally rewrites most of them even when no
+version moves. That is deliberate: it makes tooling changes visible in review.
 
 ## Regenerating
 

nix/check-tools/macos.txt

@@ -1,47 +1,143 @@
 Detected OS: macos (Darwin arm64)
 
 Core build tools:
-  [ ok ] cmake                cmake version 4.1.2
-  [ ok ] conan                Conan version 2.28.1
-  [ ok ] git                  git version 2.54.0
-  [ ok ] python3              Python 3.13.13
+  ✅ cmake
+     cmake version 4.1.2
+     /nix/store/gvabsb4yqb5xsqzqph54rijnn4zpihnp-cmake-4.1.2/bin/cmake
+  ✅ conan
+     Conan version 2.28.1
+     /nix/store/9jiyxmkpwmn6dcqs0765s83riw3l5ail-conan-2.28.1/bin/conan
+  ✅ git
+     git version 2.54.0
+     /nix/store/a14yxcqvv9x2l9mllgpirzhvz93pgprg-git-2.54.0/bin/git
+  ✅ python3
+     Python 3.13.13
+     /nix/store/ygxqin6ydzjfawywqpp5pal8wv6sf5bh-python3-3.13.13/bin/python3.13
 
 Development tooling:
-  [ ok ] ccache               ccache version 4.13.6
-  [ ok ] clang                clang version 22.1.7
-  [ ok ] clang++              clang version 22.1.7
-  [ ok ] ClangBuildAnalyzer   ClangBuildAnalyzer 1.6.0
-  [ ok ] curl                 curl 8.20.0 (aarch64-apple-darwin25.3.0) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
-  [ ok ] file                 file-5.47
-  [ ok ] less                 less 692 (PCRE2 regular expressions)
-  [ ok ] make                 GNU Make 4.4.1
-  [ ok ] netstat              present
-  [ ok ] ninja                1.13.2
-  [ ok ] perl                 v5.42.0
-  [ ok ] pkg-config           0.29.2
-  [ ok ] vim                  VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
-  [ ok ] zip                  Zip 3.0
-  [ ok ] clang-format         clang-format version 22.1.7
-  [ ok ] dot                  dot - graphviz version 12.2.1 (0)
-  [ ok ] doxygen              1.16.1
-  [ ok ] gcovr                gcovr 8.4
-  [ ok ] gh                   gh version 2.94.0 (nixpkgs)
-  [ ok ] git-cliff            git-cliff 2.13.1
-  [ ok ] git-lfs              git-lfs/3.7.1 (3.7.1; darwin arm64; go 1.26.3)
-  [ ok ] gpg                  gpg (GnuPG) 2.4.9
-  [ ok ] pre-commit           pre-commit 4.5.1
-  [ ok ] run-clang-tidy       usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+  ✅ ccache
+     ccache version 4.13.6
+     /nix/store/57davyvs6p6dkrl3svzwg1ph18wsy4cz-ccache-4.13.6/bin/ccache
+  ✅ clang
+     clang version 22.1.7
+     /nix/store/192glrb2cldvziyf3378mzjqbzx3ih4g-clang-wrapper-22.1.7/bin/clang
+  ✅ clang-22
+     clang version 22.1.7
+     /nix/store/rbap7zqq7mw00fyqa02p5rj7gqjp4w5i-clang-22/bin/clang-22
+  ✅ clang++
+     clang version 22.1.7
+     /nix/store/192glrb2cldvziyf3378mzjqbzx3ih4g-clang-wrapper-22.1.7/bin/clang++
+  ✅ clang++-22
+     clang version 22.1.7
+     /nix/store/v9haf787f7bcz0mq1sad4bpyx21pj6li-clang++-22/bin/clang++-22
+  ✅ ClangBuildAnalyzer
+     ClangBuildAnalyzer 1.6.0
+     /nix/store/4l50ds9fa2mkvh7wg8qzrlbmjs12sb8l-clangbuildanalyzer-1.6.0/bin/ClangBuildAnalyzer
+  ✅ curl
+     curl 8.20.0 (aarch64-apple-darwin25.3.0) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
+     /nix/store/kclq0czaxvsgh4ym9ld7b6iwy50l1snk-curl-8.20.0-bin/bin/curl
+  ✅ file
+     file-5.47
+     /nix/store/dax63li7wwcbqxxkkgzc4g2rx7d4w86x-file-5.47/bin/file
+  ✅ less
+     less 692 (PCRE2 regular expressions)
+     /nix/store/lvr16y75r1pdxpdv0aph5ak2yd0hkvqm-less-692/bin/less
+  ✅ make
+     GNU Make 4.4.1
+     /nix/store/8wwiw8pwyhrkzyq28hqzxfl4z84lks81-gnumake-4.4.1/bin/make
+  ✅ netstat
+     present
+     /nix/store/qsd1kzqb0ahrk433vmyl245gp623j19s-network_cmds-730.80.3/bin/netstat
+  ✅ ninja
+     1.13.2
+     /nix/store/bqykhrblarkj4fl0hz2mf8ngwfv6x6bz-ninja-1.13.2/bin/ninja
+  ✅ perl
+     v5.42.0
+     /nix/store/js13ri9fvm0ajk1fpd3acigys2a9whdv-perl-5.42.0/bin/perl
+  ✅ pkg-config
+     0.29.2
+     /nix/store/lzrwr375jqhhbca116kja96xf1md83l8-pkg-config-wrapper-0.29.2/bin/pkg-config
+  ✅ vim
+     VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
+     /nix/store/6vbkykg92w603c0sw3mkk7p7mfaawbns-vim-9.2.0389/bin/vim
+  ✅ zip
+     Zip 3.0
+     /nix/store/z6ph729vcakbvz3wh8ln1wk6mi06w487-zip-3.0/bin/zip
+  ✅ clang-apply-replacements
+     clang-apply-replacements version 22.1.7
+     /nix/store/vzyyjf3cm1hbj9wcr2qcb66x6j98zpy7-clang-tools-22.1.7/bin/clang-apply-replacements
+  ✅ clang-apply-replacements-22
+     clang-apply-replacements version 22.1.7
+     /nix/store/m3ii69rca4077lf4wlk7m3jcag1fs577-clang-apply-replacements-22/bin/clang-apply-replacements-22
+  ✅ clang-format
+     clang-format version 22.1.7
+     /nix/store/vzyyjf3cm1hbj9wcr2qcb66x6j98zpy7-clang-tools-22.1.7/bin/clang-format
+  ✅ clang-format-22
+     clang-format version 22.1.7
+     /nix/store/4fawqy6ngqcsqd2ygyyzm93q0xy3f5gs-clang-format-22/bin/clang-format-22
+  ✅ clang-tidy
+     LLVM version 22.1.7
+     /nix/store/vzyyjf3cm1hbj9wcr2qcb66x6j98zpy7-clang-tools-22.1.7/bin/clang-tidy
+  ✅ clang-tidy-22
+     LLVM version 22.1.7
+     /nix/store/jqw4280saixaxxihwdba9ldm2fsm6dr3-clang-tidy-22/bin/clang-tidy-22
+  ✅ dot
+     dot - graphviz version 12.2.1 (0)
+     /nix/store/ijb4fbnqa6wzlpqnhb6q9knqpf7qqn5z-graphviz-12.2.1/bin/dot
+  ✅ doxygen
+     1.16.1
+     /nix/store/kbryjdpq9jizjb0ws0nzbf2h2ymbdiwm-doxygen-1.16.1/bin/doxygen
+  ✅ gcovr
+     gcovr 8.4
+     /nix/store/wn8jiyh9p0bybs96s4163qp3k8vfmczx-python3.13-gcovr-8.4/bin/gcovr
+  ✅ gh
+     gh version 2.94.0 (nixpkgs)
+     /nix/store/fhnpw0hs0gjms1ha6ap02jq7rx13gkbp-gh-2.94.0/bin/gh
+  ✅ git-cliff
+     git-cliff 2.13.1
+     /nix/store/cy0wwhgxa7yvrz97zydbq6sqmixc90fq-git-cliff-2.13.1/bin/git-cliff
+  ✅ git-lfs
+     git-lfs/3.7.1 (3.7.1; darwin arm64; go 1.26.3)
+     /nix/store/k9r7zjfjplqa4d5s71cqvf2iv73jd9mc-git-lfs-3.7.1/bin/git-lfs
+  ✅ gpg
+     gpg (GnuPG) 2.4.9
+     /nix/store/cgh6iwzz5jgx9z5whka4vgj210i6npc6-gnupg-2.4.9/bin/gpg
+  ✅ pre-commit
+     pre-commit 4.5.1
+     /nix/store/z3cca68620w0w10f090szgzdnmh1waf2-pre-commit-4.5.1/bin/pre-commit
+  ✅ run-clang-tidy
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/4x28x911z2f9y7adqlh3qspp4a16dig7-run-clang-tidy/bin/run-clang-tidy
+  ✅ run-clang-tidy-22
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/x8iymrh76sk5q91ryg5pa7i32s6gfh34-run-clang-tidy-22/bin/run-clang-tidy-22
 
 Rust toolchain:
-  [ ok ] cargo                cargo 1.95.0 (f2d3ce0bd 2026-03-21)
-  [ ok ] cargo-audit          cargo-audit-audit 0.22.1
-  [ ok ] cargo-llvm-cov       cargo-llvm-cov 0.8.5
-  [ ok ] cargo-nextest        cargo-nextest 0.9.137
-  [ ok ] clippy               clippy 0.1.95 (59807616e1 2026-04-14)
-  [ ok ] rust-analyzer        rust-analyzer 1.95.0 (59807616 2026-04-14)
-  [ ok ] rustc                rustc 1.95.0 (59807616e 2026-04-14)
-  [ ok ] rustfmt              rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+  ✅ cargo
+     cargo 1.95.0 (f2d3ce0bd 2026-03-21)
+     /nix/store/92vz1f4kislnj58j1pr1788l688py6f0-rust-minimal-1.95.0/bin/cargo
+  ✅ cargo-audit
+     cargo-audit-audit 0.22.1
+     /nix/store/snwkga2f5gyf404h7mmp9wriwxb8v65f-cargo-audit-0.22.1/bin/cargo-audit
+  ✅ cargo-llvm-cov
+     cargo-llvm-cov 0.8.5
+     /nix/store/fpiqdh91gwyxalqp409ynm0s0g086w7w-cargo-llvm-cov-0.8.5/bin/cargo-llvm-cov
+  ✅ cargo-nextest
+     cargo-nextest 0.9.137
+     /nix/store/ylz7m947mhkgsp6i7611id3s3gcd58nq-cargo-nextest-0.9.137/bin/cargo-nextest
+  ✅ clippy-driver
+     clippy 0.1.95 (59807616e1 2026-04-14)
+     /nix/store/92vz1f4kislnj58j1pr1788l688py6f0-rust-minimal-1.95.0/bin/clippy-driver
+  ✅ rust-analyzer
+     rust-analyzer 1.95.0 (59807616 2026-04-14)
+     /nix/store/jqvjap2727r9cjpr25fkw5glv2kbxrdx-rust-analyzer-preview-1.95.0-aarch64-apple-darwin/bin/rust-analyzer
+  ✅ rustc
+     rustc 1.95.0 (59807616e 2026-04-14)
+     /nix/store/92vz1f4kislnj58j1pr1788l688py6f0-rust-minimal-1.95.0/bin/rustc
+  ✅ rustfmt
+     rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+     /nix/store/03x750yj6fakl7shbhicpnkxiwqxjrrs-rustfmt-preview-1.95.0-aarch64-apple-darwin/bin/rustfmt
 
 Skipping git-over-HTTPS check (CHECK_TOOLS_SKIP_CLONE is set).
 
-All 36 checked tools are present and runnable.
+✅ All 44 checked tools are present and runnable.

nix/check-tools/nix-ubuntu-amd64.txt

@@ -1,55 +1,171 @@
 Detected OS: linux (Linux x86_64)
 
 Core build tools:
-  [ ok ] cmake                cmake version 4.1.2
-  [ ok ] conan                Conan version 2.28.1
-  [ ok ] git                  git version 2.54.0
-  [ ok ] python3              Python 3.13.13
+  ✅ cmake
+     cmake version 4.1.2
+     /nix/store/r9941n32g4wyvggz2703dlplbdq8a6rd-cmake-4.1.2/bin/cmake
+  ✅ conan
+     Conan version 2.28.1
+     /nix/store/lxny9y4jvjdws7hgz1mygvb7hjrpmna5-conan-2.28.1/bin/conan
+  ✅ git
+     git version 2.54.0
+     /nix/store/bcnisk3ydfgv26v2gw3zlky24g00yww2-git-2.54.0/bin/git
+  ✅ python3
+     Python 3.13.13
+     /nix/store/60m4rxhg2fldqaak400c0lry96ijrzqn-python3-3.13.13/bin/python3.13
 
 Development tooling:
-  [ ok ] ccache               ccache version 4.13.6
-  [ ok ] clang                clang version 22.1.7
-  [ ok ] clang++              clang version 22.1.7
-  [ ok ] ClangBuildAnalyzer   ClangBuildAnalyzer 1.6.0
-  [ ok ] curl                 curl 8.20.0 (x86_64-pc-linux-gnu) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
-  [ ok ] file                 file-5.47
-  [ ok ] less                 less 692 (PCRE2 regular expressions)
-  [ ok ] make                 GNU Make 4.4.1
-  [ ok ] netstat              net-tools 2.10
-  [ ok ] ninja                1.13.2
-  [ ok ] perl                 v5.42.0
-  [ ok ] pkg-config           0.29.2
-  [ ok ] vim                  VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
-  [ ok ] zip                  Zip 3.0
-  [ ok ] clang-format         clang-format version 22.1.7
-  [ ok ] dot                  dot - graphviz version 12.2.1 (0)
-  [ ok ] doxygen              1.16.1
-  [ ok ] gcovr                gcovr 8.4
-  [ ok ] gh                   gh version 2.94.0 (nixpkgs)
-  [ ok ] git-cliff            git-cliff 2.13.1
-  [ ok ] git-lfs              git-lfs/3.7.1 (3.7.1; linux amd64; go 1.26.3)
-  [ ok ] gpg                  gpg (GnuPG) 2.4.9
-  [ ok ] pre-commit           pre-commit 4.5.1
-  [ ok ] run-clang-tidy       usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+  ✅ ccache
+     ccache version 4.13.6
+     /nix/store/c9wwl7s5i6rsfwvf4v0xbbmzx5m6jgfr-ccache-4.13.6/bin/ccache
+  ✅ clang
+     clang version 22.1.7
+     /nix/store/ff0hrp9r9i3pa5arkdw0sgmzp8d576qi-clang-wrapper-22.1.7/bin/clang
+  ✅ clang-22
+     clang version 22.1.7
+     /nix/store/dagc2rq44gfbr7w7yvvqca3yqpc9gqbq-clang-22/bin/clang-22
+  ✅ clang++
+     clang version 22.1.7
+     /nix/store/ff0hrp9r9i3pa5arkdw0sgmzp8d576qi-clang-wrapper-22.1.7/bin/clang++
+  ✅ clang++-22
+     clang version 22.1.7
+     /nix/store/l5m8clin1npl605wdkd8mr18ggxww3z4-clang++-22/bin/clang++-22
+  ✅ ClangBuildAnalyzer
+     ClangBuildAnalyzer 1.6.0
+     /nix/store/bshlmn8fqw55nsnm581xqlfbahfkykxx-clangbuildanalyzer-1.6.0/bin/ClangBuildAnalyzer
+  ✅ curl
+     curl 8.20.0 (x86_64-pc-linux-gnu) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
+     /nix/store/zbwymrp4lcfjc4kkk0n4779v0kjjz58z-curl-8.20.0-bin/bin/curl
+  ✅ file
+     file-5.47
+     /nix/store/bizyfqdw0h67wzqmp10knmf9s2pqahdb-file-5.47/bin/file
+  ✅ less
+     less 692 (PCRE2 regular expressions)
+     /nix/store/c6bacbn93qg4a7g9n4czww8rg24dvysr-less-692/bin/less
+  ✅ make
+     GNU Make 4.4.1
+     /nix/store/d3bwqm6bymhy3pdgbvf7vxjqfp31m3j1-gnumake-4.4.1/bin/make
+  ✅ netstat
+     net-tools 2.10
+     /nix/store/jmyzqvgflnswmws7rnxx6g3zbj680xvd-net-tools-2.10/bin/netstat
+  ✅ ninja
+     1.13.2
+     /nix/store/7a235m7crqbb4h49sak20fqxpw3n7hr0-ninja-1.13.2/bin/ninja
+  ✅ perl
+     v5.42.0
+     /nix/store/6plwsm6pkq79yjv4xvy8csk2pd4hzr67-perl-5.42.0/bin/perl
+  ✅ pkg-config
+     0.29.2
+     /nix/store/1m05k7xgfnw6jc21xxk5681ni3ar97wf-pkg-config-wrapper-0.29.2/bin/pkg-config
+  ✅ vim
+     VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
+     /nix/store/hvyqx52g4g2fxhgpans3fksjj6lmlyaw-vim-9.2.0389/bin/vim
+  ✅ zip
+     Zip 3.0
+     /nix/store/qnd2ag67hrjj0b6vbmisdshf50r6s72n-zip-3.0/bin/zip
+  ✅ clang-apply-replacements
+     clang-apply-replacements version 22.1.7
+     /nix/store/4zp1rjpj2xijrv4kqpwsy3ixwb2r6nlk-clang-tools-22.1.7/bin/clang-apply-replacements
+  ✅ clang-apply-replacements-22
+     clang-apply-replacements version 22.1.7
+     /nix/store/py2wihg0a96qcppv4hjmww547xabr0fb-clang-apply-replacements-22/bin/clang-apply-replacements-22
+  ✅ clang-format
+     clang-format version 22.1.7
+     /nix/store/4zp1rjpj2xijrv4kqpwsy3ixwb2r6nlk-clang-tools-22.1.7/bin/clang-format
+  ✅ clang-format-22
+     clang-format version 22.1.7
+     /nix/store/kz820ccifjlwqnwqjsx7kbiajrgsmbrh-clang-format-22/bin/clang-format-22
+  ✅ clang-tidy
+     LLVM version 22.1.7
+     /nix/store/4zp1rjpj2xijrv4kqpwsy3ixwb2r6nlk-clang-tools-22.1.7/bin/clang-tidy
+  ✅ clang-tidy-22
+     LLVM version 22.1.7
+     /nix/store/gdrkvpw846lkyzh8y9p3zx50g6ml2v84-clang-tidy-22/bin/clang-tidy-22
+  ✅ dot
+     dot - graphviz version 12.2.1 (0)
+     /nix/store/12rgns2296s4qcja778gvcbx61z77rc4-graphviz-12.2.1/bin/dot
+  ✅ doxygen
+     1.16.1
+     /nix/store/k0vzr5lvgq1byraknzwvk51wcgpnsrkh-doxygen-1.16.1/bin/doxygen
+  ✅ gcovr
+     gcovr 8.4
+     /nix/store/iyzi7fpyclqrha054adnizvif02lg49x-python3.13-gcovr-8.4/bin/gcovr
+  ✅ gh
+     gh version 2.94.0 (nixpkgs)
+     /nix/store/pidh15szlsb1vc41xdsa3xbdghdazvby-gh-2.94.0/bin/gh
+  ✅ git-cliff
+     git-cliff 2.13.1
+     /nix/store/1q851fs62shgjhc03fxxdkpzxdjg7k11-git-cliff-2.13.1/bin/git-cliff
+  ✅ git-lfs
+     git-lfs/3.7.1 (3.7.1; linux amd64; go 1.26.3)
+     /nix/store/6ljwpal7b1756708m33vj0crpral7mvl-git-lfs-3.7.1/bin/git-lfs
+  ✅ gpg
+     gpg (GnuPG) 2.4.9
+     /nix/store/wx7vk8babxkgy813r70yc67vcwnmagbx-gnupg-2.4.9/bin/gpg
+  ✅ pre-commit
+     pre-commit 4.5.1
+     /nix/store/bj6i9vl34cij5h0r165y40hrjqak0bmz-pre-commit-4.5.1/bin/pre-commit
+  ✅ run-clang-tidy
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/sbg911hs9dbclrzlp04br3iyfpgnaj6r-run-clang-tidy/bin/run-clang-tidy
+  ✅ run-clang-tidy-22
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/n8yak1ap308gvi7gmrniw0ybsx80fjws-run-clang-tidy-22/bin/run-clang-tidy-22
 
 Rust toolchain:
-  [ ok ] cargo                cargo 1.95.0 (f2d3ce0bd 2026-03-21)
-  [ ok ] cargo-audit          cargo-audit-audit 0.22.1
-  [ ok ] cargo-llvm-cov       cargo-llvm-cov 0.8.5
-  [ ok ] cargo-nextest        cargo-nextest 0.9.137
-  [ ok ] clippy               clippy 0.1.95 (59807616e1 2026-04-14)
-  [ ok ] rust-analyzer        rust-analyzer 1.95.0 (5980761 2026-04-14)
-  [ ok ] rustc                rustc 1.95.0 (59807616e 2026-04-14)
-  [ ok ] rustfmt              rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+  ✅ cargo
+     cargo 1.95.0 (f2d3ce0bd 2026-03-21)
+     /nix/store/85qbwr3vzfs58m7ywnjblz105p8ahbrv-cargo-1.95.0-x86_64-unknown-linux-gnu/bin/cargo
+  ✅ cargo-audit
+     cargo-audit-audit 0.22.1
+     /nix/store/2w9if868piw98xz057sz97jnjvf7hnvf-cargo-audit-0.22.1/bin/cargo-audit
+  ✅ cargo-llvm-cov
+     cargo-llvm-cov 0.8.5
+     /nix/store/jjpdf1l6izz6607a346ykra9sndzaw7h-cargo-llvm-cov-0.8.5/bin/cargo-llvm-cov
+  ✅ cargo-nextest
+     cargo-nextest 0.9.137
+     /nix/store/jhkr7gwyrchkml33gyns9cy0yn7b57qc-cargo-nextest-0.9.137/bin/cargo-nextest
+  ✅ clippy-driver
+     clippy 0.1.95 (59807616e1 2026-04-14)
+     /nix/store/bnvg9nmdq4g98dd9v3r6nvjg5h2rr8i7-rust-minimal-1.95.0/bin/clippy-driver
+  ✅ rust-analyzer
+     rust-analyzer 1.95.0 (5980761 2026-04-14)
+     /nix/store/i3cnpngfwa3k4jn431pl6ji1r4qmxky9-rust-analyzer-preview-1.95.0-x86_64-unknown-linux-gnu/bin/rust-analyzer
+  ✅ rustc
+     rustc 1.95.0 (59807616e 2026-04-14)
+     /nix/store/bnvg9nmdq4g98dd9v3r6nvjg5h2rr8i7-rust-minimal-1.95.0/bin/rustc
+  ✅ rustfmt
+     rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+     /nix/store/366hhk2dgwxmnf4hgrj4b8llhjr3hf0i-rustfmt-preview-1.95.0-x86_64-unknown-linux-gnu/bin/rustfmt
 
 GCC toolchain:
-  [ ok ] gcc                  gcc (GCC) 15.2.0
-  [ ok ] g++                  g++ (GCC) 15.2.0
-  [ ok ] gcov                 gcov (GCC) 15.2.0
+  ✅ gcc
+     gcc (GCC) 15.2.0
+     /nix/store/3dd6y3pq00i3r85l45jvz63wjya403nl-gcc-wrapper-15.2.0/bin/gcc
+  ✅ gcc-15
+     gcc (GCC) 15.2.0
+     /nix/store/d6iri2s6bzqq5ac3fg25j6hgnn1lz44f-gcc-15/bin/gcc-15
+  ✅ g++
+     g++ (GCC) 15.2.0
+     /nix/store/3dd6y3pq00i3r85l45jvz63wjya403nl-gcc-wrapper-15.2.0/bin/g++
+  ✅ g++-15
+     g++ (GCC) 15.2.0
+     /nix/store/gm3msmmxq055lm9gprkfjj9d2gdz1mpg-g++-15/bin/g++-15
+  ✅ cpp
+     cpp (GCC) 15.2.0
+     /nix/store/3dd6y3pq00i3r85l45jvz63wjya403nl-gcc-wrapper-15.2.0/bin/cpp
+  ✅ cpp-15
+     cpp (GCC) 15.2.0
+     /nix/store/bn3gmn0m7g4gn2i0yml46fljc7mghiq5-cpp-15/bin/cpp-15
+  ✅ gcov
+     gcov (GCC) 15.2.0
+     /nix/store/xvv5sm5i8x0ks6ypfkzl7c4j9srnxz7k-gcc-15.2.0/bin/gcov
 
 Mold:
-  [ ok ] mold                 mold 2.41.0 (compatible with GNU ld)
+  ✅ mold
+     mold 2.41.0 (compatible with GNU ld)
+     /nix/store/2w6fpgxjzzyqmd25wzplm23dfa49a0p2-mold-unwrapped-wrapper-2.41.0/bin/mold
 
 Skipping git-over-HTTPS check (CHECK_TOOLS_SKIP_CLONE is set).
 
-All 40 checked tools are present and runnable.
+✅ All 52 checked tools are present and runnable.

nix/check-tools/nix-ubuntu-arm64.txt

@@ -1,55 +1,171 @@
 Detected OS: linux (Linux aarch64)
 
 Core build tools:
-  [ ok ] cmake                cmake version 4.1.2
-  [ ok ] conan                Conan version 2.28.1
-  [ ok ] git                  git version 2.54.0
-  [ ok ] python3              Python 3.13.13
+  ✅ cmake
+     cmake version 4.1.2
+     /nix/store/nkcpxjifkambzlrwh27a8igvhnbchibg-cmake-4.1.2/bin/cmake
+  ✅ conan
+     Conan version 2.28.1
+     /nix/store/8i2gyqgc00xvxg9xm6y7n0ilncdv8imw-conan-2.28.1/bin/conan
+  ✅ git
+     git version 2.54.0
+     /nix/store/ixp98f9avf8ikpdrmp40cj33g0dazyp9-git-2.54.0/bin/git
+  ✅ python3
+     Python 3.13.13
+     /nix/store/lqn6mbgzzdrqq2qkwddcmxj9z6amdd86-python3-3.13.13/bin/python3.13
 
 Development tooling:
-  [ ok ] ccache               ccache version 4.13.6
-  [ ok ] clang                clang version 22.1.7
-  [ ok ] clang++              clang version 22.1.7
-  [ ok ] ClangBuildAnalyzer   ClangBuildAnalyzer 1.6.0
-  [ ok ] curl                 curl 8.20.0 (aarch64-unknown-linux-gnu) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
-  [ ok ] file                 file-5.47
-  [ ok ] less                 less 692 (PCRE2 regular expressions)
-  [ ok ] make                 GNU Make 4.4.1
-  [ ok ] netstat              net-tools 2.10
-  [ ok ] ninja                1.13.2
-  [ ok ] perl                 v5.42.0
-  [ ok ] pkg-config           0.29.2
-  [ ok ] vim                  VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
-  [ ok ] zip                  Zip 3.0
-  [ ok ] clang-format         clang-format version 22.1.7
-  [ ok ] dot                  dot - graphviz version 12.2.1 (0)
-  [ ok ] doxygen              1.16.1
-  [ ok ] gcovr                gcovr 8.4
-  [ ok ] gh                   gh version 2.94.0 (nixpkgs)
-  [ ok ] git-cliff            git-cliff 2.13.1
-  [ ok ] git-lfs              git-lfs/3.7.1 (3.7.1; linux arm64; go 1.26.3)
-  [ ok ] gpg                  gpg (GnuPG) 2.4.9
-  [ ok ] pre-commit           pre-commit 4.5.1
-  [ ok ] run-clang-tidy       usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+  ✅ ccache
+     ccache version 4.13.6
+     /nix/store/2q39xi2kbi04ibga7635f2sl148d1mzv-ccache-4.13.6/bin/ccache
+  ✅ clang
+     clang version 22.1.7
+     /nix/store/xjqffrq9i7la058s9865ig71l9sp1ys5-clang-wrapper-22.1.7/bin/clang
+  ✅ clang-22
+     clang version 22.1.7
+     /nix/store/vcf6ilfwn57828hwzyp6zlyr24j9j6yw-clang-22/bin/clang-22
+  ✅ clang++
+     clang version 22.1.7
+     /nix/store/xjqffrq9i7la058s9865ig71l9sp1ys5-clang-wrapper-22.1.7/bin/clang++
+  ✅ clang++-22
+     clang version 22.1.7
+     /nix/store/xby0f6gamr7m27zp5cndsvghbp9lgb3c-clang++-22/bin/clang++-22
+  ✅ ClangBuildAnalyzer
+     ClangBuildAnalyzer 1.6.0
+     /nix/store/h893hd4q1bb6ily2lby5dzyfrrzd2nvj-clangbuildanalyzer-1.6.0/bin/ClangBuildAnalyzer
+  ✅ curl
+     curl 8.20.0 (aarch64-unknown-linux-gnu) libcurl/8.20.0 OpenSSL/3.6.2 zlib/1.3.2 libssh2/1.11.1 nghttp2/1.69.0 mit-krb5/1.22.1
+     /nix/store/i1s0lqwlrmjd2dxzgy2p84cxqqsb0bmk-curl-8.20.0-bin/bin/curl
+  ✅ file
+     file-5.47
+     /nix/store/dx973zg9km2w9albsib2vw9wyvacfrlw-file-5.47/bin/file
+  ✅ less
+     less 692 (PCRE2 regular expressions)
+     /nix/store/1blb3s7hhsr77wqi598m6k1qkfp3ms0w-less-692/bin/less
+  ✅ make
+     GNU Make 4.4.1
+     /nix/store/9ngw1ippk25jjj5fjxv36xbp6iq7rxdx-gnumake-4.4.1/bin/make
+  ✅ netstat
+     net-tools 2.10
+     /nix/store/7vdsz21f0s499s5yyqzp5s4676q4yxdd-net-tools-2.10/bin/netstat
+  ✅ ninja
+     1.13.2
+     /nix/store/8ksx98gsbn5lmlizcmw57yd4sg0k2p58-ninja-1.13.2/bin/ninja
+  ✅ perl
+     v5.42.0
+     /nix/store/5wnly69vv1i3y97al4v3xrqymf9hlzgq-perl-5.42.0/bin/perl
+  ✅ pkg-config
+     0.29.2
+     /nix/store/c7vwy0gl1q0agl2h22gi0m9dg7xxad2l-pkg-config-wrapper-0.29.2/bin/pkg-config
+  ✅ vim
+     VIM - Vi IMproved 9.2 (2026 Feb 14, compiled Jan 01 1980 00:00:00)
+     /nix/store/v8c7pvx26irvy9k5sbwd183cyvckzzb3-vim-9.2.0389/bin/vim
+  ✅ zip
+     Zip 3.0
+     /nix/store/5mh19mvbv9ym2sm9vymyyaac5l2cj2jq-zip-3.0/bin/zip
+  ✅ clang-apply-replacements
+     clang-apply-replacements version 22.1.7
+     /nix/store/s53p2m776iqaz7acgr5csgpsd18w15h7-clang-tools-22.1.7/bin/clang-apply-replacements
+  ✅ clang-apply-replacements-22
+     clang-apply-replacements version 22.1.7
+     /nix/store/bg4kn8z81hk7b9284rjqvr51wpfjqc24-clang-apply-replacements-22/bin/clang-apply-replacements-22
+  ✅ clang-format
+     clang-format version 22.1.7
+     /nix/store/s53p2m776iqaz7acgr5csgpsd18w15h7-clang-tools-22.1.7/bin/clang-format
+  ✅ clang-format-22
+     clang-format version 22.1.7
+     /nix/store/79v57mzcw8ng8kl7p961ck08ymhp31v7-clang-format-22/bin/clang-format-22
+  ✅ clang-tidy
+     LLVM version 22.1.7
+     /nix/store/s53p2m776iqaz7acgr5csgpsd18w15h7-clang-tools-22.1.7/bin/clang-tidy
+  ✅ clang-tidy-22
+     LLVM version 22.1.7
+     /nix/store/wdyd6cb9z1lyi37lbzvwldgcc7yv1n5c-clang-tidy-22/bin/clang-tidy-22
+  ✅ dot
+     dot - graphviz version 12.2.1 (0)
+     /nix/store/58rrk4yzwpmyxvl8cqm18h3dhv24zf00-graphviz-12.2.1/bin/dot
+  ✅ doxygen
+     1.16.1
+     /nix/store/hq32kzwpl89wgr49iq0gmqn9r5n072zq-doxygen-1.16.1/bin/doxygen
+  ✅ gcovr
+     gcovr 8.4
+     /nix/store/sml3xbbfhhlhk6h7jnlg19pdbx9b764b-python3.13-gcovr-8.4/bin/gcovr
+  ✅ gh
+     gh version 2.94.0 (nixpkgs)
+     /nix/store/7hh2qi0gj2ifbxbl56cjzbiyfc379bji-gh-2.94.0/bin/gh
+  ✅ git-cliff
+     git-cliff 2.13.1
+     /nix/store/bidn3pz53yd6qlg711917xx0q10hqmqv-git-cliff-2.13.1/bin/git-cliff
+  ✅ git-lfs
+     git-lfs/3.7.1 (3.7.1; linux arm64; go 1.26.3)
+     /nix/store/4rsklvkbac5bayy0zv12kxyvspi4sshd-git-lfs-3.7.1/bin/git-lfs
+  ✅ gpg
+     gpg (GnuPG) 2.4.9
+     /nix/store/ka4i8zz5ni3rzqnzcxbfvwr95fk8pn6q-gnupg-2.4.9/bin/gpg
+  ✅ pre-commit
+     pre-commit 4.5.1
+     /nix/store/n981w6hjfar2l81kxbxs2wxl64vwa5kj-pre-commit-4.5.1/bin/pre-commit
+  ✅ run-clang-tidy
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/4z2fyklg78klallr7x9j02kz92hnxp4m-run-clang-tidy/bin/run-clang-tidy
+  ✅ run-clang-tidy-22
+     usage: run-clang-tidy [-h] [-allow-enabling-alpha-checkers]
+     /nix/store/f8m0p9ad40brp9ahy4i0h27kqjkya1j9-run-clang-tidy-22/bin/run-clang-tidy-22
 
 Rust toolchain:
-  [ ok ] cargo                cargo 1.95.0 (f2d3ce0bd 2026-03-21)
-  [ ok ] cargo-audit          cargo-audit-audit 0.22.1
-  [ ok ] cargo-llvm-cov       cargo-llvm-cov 0.8.5
-  [ ok ] cargo-nextest        cargo-nextest 0.9.137
-  [ ok ] clippy               clippy 0.1.95 (59807616e1 2026-04-14)
-  [ ok ] rust-analyzer        rust-analyzer 1.95.0 (5980761 2026-04-14)
-  [ ok ] rustc                rustc 1.95.0 (59807616e 2026-04-14)
-  [ ok ] rustfmt              rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+  ✅ cargo
+     cargo 1.95.0 (f2d3ce0bd 2026-03-21)
+     /nix/store/yw1rs50s6qpsw0zyl7j3dpm18swbl0ag-cargo-1.95.0-aarch64-unknown-linux-gnu/bin/cargo
+  ✅ cargo-audit
+     cargo-audit-audit 0.22.1
+     /nix/store/9rxbrn9aa2r1z96186s69pc7vzizyfch-cargo-audit-0.22.1/bin/cargo-audit
+  ✅ cargo-llvm-cov
+     cargo-llvm-cov 0.8.5
+     /nix/store/vwjsi159n89szrx4yh5pc3jlf2gp4fld-cargo-llvm-cov-0.8.5/bin/cargo-llvm-cov
+  ✅ cargo-nextest
+     cargo-nextest 0.9.137
+     /nix/store/qb6bcg2fjvm3r9s9j98nmffmf9xwh45s-cargo-nextest-0.9.137/bin/cargo-nextest
+  ✅ clippy-driver
+     clippy 0.1.95 (59807616e1 2026-04-14)
+     /nix/store/nz4qv12pf16c092qr9hh4dsn0fzf47da-rust-minimal-1.95.0/bin/clippy-driver
+  ✅ rust-analyzer
+     rust-analyzer 1.95.0 (5980761 2026-04-14)
+     /nix/store/m1rn67sqfz8s44idcxqallg680ifk71r-rust-analyzer-preview-1.95.0-aarch64-unknown-linux-gnu/bin/rust-analyzer
+  ✅ rustc
+     rustc 1.95.0 (59807616e 2026-04-14)
+     /nix/store/nz4qv12pf16c092qr9hh4dsn0fzf47da-rust-minimal-1.95.0/bin/rustc
+  ✅ rustfmt
+     rustfmt 1.9.0-stable (59807616e1 2026-04-14)
+     /nix/store/jidfsprj2820glyzjn54ldn3j1fmz8c5-rustfmt-preview-1.95.0-aarch64-unknown-linux-gnu/bin/rustfmt
 
 GCC toolchain:
-  [ ok ] gcc                  gcc (GCC) 15.2.0
-  [ ok ] g++                  g++ (GCC) 15.2.0
-  [ ok ] gcov                 gcov (GCC) 15.2.0
+  ✅ gcc
+     gcc (GCC) 15.2.0
+     /nix/store/rn6svg593xsmn8qcjzk8x9pa1i62c4kb-gcc-wrapper-15.2.0/bin/gcc
+  ✅ gcc-15
+     gcc (GCC) 15.2.0
+     /nix/store/h489d1rmjisfbxh5kmsb0a7c35j8qsdf-gcc-15/bin/gcc-15
+  ✅ g++
+     g++ (GCC) 15.2.0
+     /nix/store/rn6svg593xsmn8qcjzk8x9pa1i62c4kb-gcc-wrapper-15.2.0/bin/g++
+  ✅ g++-15
+     g++ (GCC) 15.2.0
+     /nix/store/9ywmhz8bmzknrn3pn84g46z8hj3vrmw5-g++-15/bin/g++-15
+  ✅ cpp
+     cpp (GCC) 15.2.0
+     /nix/store/rn6svg593xsmn8qcjzk8x9pa1i62c4kb-gcc-wrapper-15.2.0/bin/cpp
+  ✅ cpp-15
+     cpp (GCC) 15.2.0
+     /nix/store/vmjilh1b830qz9yh0a1jj5ads0jxizdk-cpp-15/bin/cpp-15
+  ✅ gcov
+     gcov (GCC) 15.2.0
+     /nix/store/rmwf5hpi1y2m1wpnfvlxmrhksm4djk2j-gcc-15.2.0/bin/gcov
 
 Mold:
-  [ ok ] mold                 mold 2.41.0 (compatible with GNU ld)
+  ✅ mold
+     mold 2.41.0 (compatible with GNU ld)
+     /nix/store/f5qh5a0bx1dslmnf5n5gx0s6aljbswq3-mold-unwrapped-wrapper-2.41.0/bin/mold
 
 Skipping git-over-HTTPS check (CHECK_TOOLS_SKIP_CLONE is set).
 
-All 40 checked tools are present and runnable.
+✅ All 52 checked tools are present and runnable.

nix/devshell.nix

@@ -30,10 +30,29 @@ let
   };
   customGccGcov = if pkgs.stdenv.isLinux then customCompilers.customGcov else plainGcov;
 
+  # Whole directory: init.sh locates the profiles relative to itself.
+  conanDir = ../conan;
+
+  # Own Conan home, so Nix-built packages never share a cache with a system
+  # Conan. The stamp holds a content-addressed store path, so init.sh re-runs
+  # only when something in conan/ changes.
+  conanHook = ''
+    export CONAN_HOME=~/.conan2-nix
+    _xrpl_conan_stamp="$CONAN_HOME/.xrpld-devshell"
+    if [ "$(cat "$_xrpl_conan_stamp" 2>/dev/null)" != "${conanDir}" ]; then
+      if ${conanDir}/init.sh; then
+        printf '%s' "${conanDir}" >"$_xrpl_conan_stamp"
+      else
+        echo "⚠️ Conan setup failed - run ./conan/init.sh from the repository root to retry."
+      fi
+    fi
+    unset _xrpl_conan_stamp
+  '';
+
   # Shown when entering a *-plain shell. These exist only on Linux (see below),
   # where the stock toolchain diverges from CI.
   plainWarningHook = ''
-    echo "⚠️  WARNING: this is the stock nixpkgs toolchain and does not match CI's glibc. Prefer 'nix develop .#gcc' / '.#clang' unless you need to skip the custom-glibc build."
+    echo "⚠️ WARNING: this is the stock nixpkgs toolchain and does not match CI's glibc. Prefer 'nix develop .#gcc' / '.#clang' unless you need to skip the custom-glibc build."
   '';
 
   # Tools to expose under version-suffixed names (see mkVersionedToolLinks).
@@ -87,6 +106,7 @@ let
         shellHook = ''
           echo "Welcome to xrpld development shell";
           ${compilerVersionHook}
+          ${conanHook}
           ${warningHook}
         '';
       }