refactor: Modularize app/tx (#6228)

This change decouples app/tx from `Application` and `Config` to clear the way to moving transactors to `libxrpl`.

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

@@ -4,14 +4,11 @@ Loop: test.jtx test.toplevel
 Loop: test.jtx test.unit_test
   test.unit_test == test.jtx
 
-Loop: xrpld.app xrpld.core
-  xrpld.app > xrpld.core
-
 Loop: xrpld.app xrpld.overlay
-  xrpld.overlay > xrpld.app
+  xrpld.overlay ~= xrpld.app
 
 Loop: xrpld.app xrpld.peerfinder
-  xrpld.peerfinder ~= xrpld.app
+  xrpld.peerfinder == xrpld.app
 
 Loop: xrpld.app xrpld.rpc
   xrpld.rpc > xrpld.app

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

@@ -1,4 +1,6 @@
 libxrpl.basics > xrpl.basics
+libxrpl.conditions > xrpl.basics
+libxrpl.conditions > xrpl.conditions
 libxrpl.core > xrpl.basics
 libxrpl.core > xrpl.core
 libxrpl.crypto > xrpl.basics
@@ -17,16 +19,27 @@ libxrpl.nodestore > xrpl.protocol
 libxrpl.protocol > xrpl.basics
 libxrpl.protocol > xrpl.json
 libxrpl.protocol > xrpl.protocol
+libxrpl.rdb > xrpl.basics
+libxrpl.rdb > xrpl.rdb
 libxrpl.resource > xrpl.basics
 libxrpl.resource > xrpl.json
 libxrpl.resource > xrpl.resource
 libxrpl.server > xrpl.basics
 libxrpl.server > xrpl.json
 libxrpl.server > xrpl.protocol
+libxrpl.server > xrpl.rdb
 libxrpl.server > xrpl.server
 libxrpl.shamap > xrpl.basics
 libxrpl.shamap > xrpl.protocol
 libxrpl.shamap > xrpl.shamap
+libxrpl.tx > xrpl.basics
+libxrpl.tx > xrpl.conditions
+libxrpl.tx > xrpl.core
+libxrpl.tx > xrpl.json
+libxrpl.tx > xrpl.ledger
+libxrpl.tx > xrpl.protocol
+libxrpl.tx > xrpl.server
+libxrpl.tx > xrpl.tx
 test.app > test.jtx
 test.app > test.rpc
 test.app > test.toplevel
@@ -41,7 +54,10 @@ test.app > xrpl.json
 test.app > xrpl.ledger
 test.app > xrpl.nodestore
 test.app > xrpl.protocol
+test.app > xrpl.rdb
 test.app > xrpl.resource
+test.app > xrpl.server
+test.app > xrpl.tx
 test.basics > test.jtx
 test.basics > test.unit_test
 test.basics > xrpl.basics
@@ -51,7 +67,7 @@ test.basics > xrpl.json
 test.basics > xrpl.protocol
 test.beast > xrpl.basics
 test.conditions > xrpl.basics
-test.conditions > xrpld.conditions
+test.conditions > xrpl.conditions
 test.consensus > test.csf
 test.consensus > test.toplevel
 test.consensus > test.unit_test
@@ -60,6 +76,7 @@ test.consensus > xrpld.app
 test.consensus > xrpld.consensus
 test.consensus > xrpl.json
 test.consensus > xrpl.ledger
+test.consensus > xrpl.tx
 test.core > test.jtx
 test.core > test.toplevel
 test.core > test.unit_test
@@ -67,6 +84,7 @@ test.core > xrpl.basics
 test.core > xrpl.core
 test.core > xrpld.core
 test.core > xrpl.json
+test.core > xrpl.rdb
 test.core > xrpl.server
 test.csf > xrpl.basics
 test.csf > xrpld.consensus
@@ -75,6 +93,7 @@ test.csf > xrpl.protocol
 test.json > test.jtx
 test.json > xrpl.json
 test.jtx > xrpl.basics
+test.jtx > xrpl.core
 test.jtx > xrpld.app
 test.jtx > xrpld.core
 test.jtx > xrpld.rpc
@@ -84,6 +103,7 @@ test.jtx > xrpl.net
 test.jtx > xrpl.protocol
 test.jtx > xrpl.resource
 test.jtx > xrpl.server
+test.jtx > xrpl.tx
 test.ledger > test.jtx
 test.ledger > test.toplevel
 test.ledger > xrpl.basics
@@ -95,8 +115,8 @@ test.nodestore > test.jtx
 test.nodestore > test.toplevel
 test.nodestore > test.unit_test
 test.nodestore > xrpl.basics
-test.nodestore > xrpld.core
 test.nodestore > xrpl.nodestore
+test.nodestore > xrpl.rdb
 test.overlay > test.jtx
 test.overlay > test.toplevel
 test.overlay > test.unit_test
@@ -129,8 +149,11 @@ test.rpc > xrpld.core
 test.rpc > xrpld.overlay
 test.rpc > xrpld.rpc
 test.rpc > xrpl.json
+test.rpc > xrpl.ledger
 test.rpc > xrpl.protocol
 test.rpc > xrpl.resource
+test.rpc > xrpl.server
+test.rpc > xrpl.tx
 test.server > test.jtx
 test.server > test.toplevel
 test.server > test.unit_test
@@ -151,40 +174,57 @@ test.unit_test > xrpl.basics
 tests.libxrpl > xrpl.basics
 tests.libxrpl > xrpl.json
 tests.libxrpl > xrpl.net
+xrpl.conditions > xrpl.basics
+xrpl.conditions > xrpl.protocol
 xrpl.core > xrpl.basics
 xrpl.core > xrpl.json
 xrpl.core > xrpl.ledger
+xrpl.core > xrpl.protocol
 xrpl.json > xrpl.basics
 xrpl.ledger > xrpl.basics
 xrpl.ledger > xrpl.protocol
+xrpl.ledger > xrpl.server
+xrpl.ledger > xrpl.shamap
 xrpl.net > xrpl.basics
 xrpl.nodestore > xrpl.basics
 xrpl.nodestore > xrpl.protocol
 xrpl.protocol > xrpl.basics
 xrpl.protocol > xrpl.json
+xrpl.rdb > xrpl.basics
+xrpl.rdb > xrpl.core
+xrpl.rdb > xrpl.protocol
 xrpl.resource > xrpl.basics
 xrpl.resource > xrpl.json
 xrpl.resource > xrpl.protocol
 xrpl.server > xrpl.basics
+xrpl.server > xrpl.core
 xrpl.server > xrpl.json
 xrpl.server > xrpl.protocol
+xrpl.server > xrpl.rdb
+xrpl.server > xrpl.resource
+xrpl.server > xrpl.shamap
 xrpl.shamap > xrpl.basics
 xrpl.shamap > xrpl.nodestore
 xrpl.shamap > xrpl.protocol
+xrpl.tx > xrpl.basics
+xrpl.tx > xrpl.core
+xrpl.tx > xrpl.ledger
+xrpl.tx > xrpl.protocol
 xrpld.app > test.unit_test
 xrpld.app > xrpl.basics
 xrpld.app > xrpl.core
-xrpld.app > xrpld.conditions
 xrpld.app > xrpld.consensus
+xrpld.app > xrpld.core
 xrpld.app > xrpl.json
 xrpld.app > xrpl.ledger
 xrpld.app > xrpl.net
 xrpld.app > xrpl.nodestore
 xrpld.app > xrpl.protocol
+xrpld.app > xrpl.rdb
 xrpld.app > xrpl.resource
+xrpld.app > xrpl.server
 xrpld.app > xrpl.shamap
-xrpld.conditions > xrpl.basics
+xrpld.app > xrpl.tx
-xrpld.conditions > xrpl.protocol
 xrpld.consensus > xrpl.basics
 xrpld.consensus > xrpl.json
 xrpld.consensus > xrpl.protocol
@@ -193,17 +233,21 @@ xrpld.core > xrpl.core
 xrpld.core > xrpl.json
 xrpld.core > xrpl.net
 xrpld.core > xrpl.protocol
+xrpld.core > xrpl.rdb
 xrpld.overlay > xrpl.basics
 xrpld.overlay > xrpl.core
 xrpld.overlay > xrpld.core
 xrpld.overlay > xrpld.peerfinder
 xrpld.overlay > xrpl.json
 xrpld.overlay > xrpl.protocol
+xrpld.overlay > xrpl.rdb
 xrpld.overlay > xrpl.resource
 xrpld.overlay > xrpl.server
+xrpld.overlay > xrpl.tx
 xrpld.peerfinder > xrpl.basics
 xrpld.peerfinder > xrpld.core
 xrpld.peerfinder > xrpl.protocol
+xrpld.peerfinder > xrpl.rdb
 xrpld.perflog > xrpl.basics
 xrpld.perflog > xrpl.core
 xrpld.perflog > xrpld.rpc
@@ -216,6 +260,8 @@ xrpld.rpc > xrpl.ledger
 xrpld.rpc > xrpl.net
 xrpld.rpc > xrpl.nodestore
 xrpld.rpc > xrpl.protocol
+xrpld.rpc > xrpl.rdb
 xrpld.rpc > xrpl.resource
 xrpld.rpc > xrpl.server
+xrpld.rpc > xrpl.tx
 xrpld.shamap > xrpl.shamap

.gitignore

@@ -71,3 +71,6 @@ DerivedData
 /.augment
 /.claude
 /CLAUDE.md
+
+# clangd cache
+/.cache

.pre-commit-config.yaml

@@ -20,7 +20,7 @@ repos:
         args: [--assume-in-merge]
 
   - repo: https://github.com/pre-commit/mirrors-clang-format
-    rev: 7d85583be209cb547946c82fbe51f4bc5dd1d017 # frozen: v18.1.8
+    rev: 75ca4ad908dc4a99f57921f29b7e6c1521e10b26 # frozen: v21.1.8
     hooks:
       - id: clang-format
         args: [--style=file]

CONTRIBUTING.md

@@ -219,7 +219,7 @@ coherent rather than a set of _thou shalt not_ commandments.
 
 ## Formatting
 
-All code must conform to `clang-format` version 18,
+All code must conform to `clang-format` version 21,
 according to the settings in [`.clang-format`](./.clang-format),
 unless the result would be unreasonably difficult to read or maintain.
 To demarcate lines that should be left as-is, surround them with comments like

cmake/CodeCoverage.cmake

@@ -466,11 +466,6 @@ function (add_code_coverage_to_target name scope)
     target_compile_options(${name} ${scope} $<$<COMPILE_LANGUAGE:CXX>:${COVERAGE_CXX_COMPILER_FLAGS}>
                            $<$<COMPILE_LANGUAGE:C>:${COVERAGE_C_COMPILER_FLAGS}>)
 
-    target_link_libraries(
+    target_link_libraries(${name} ${scope} $<$<LINK_LANGUAGE:CXX>:${COVERAGE_CXX_LINKER_FLAGS}>
-        ${name}
+                          $<$<LINK_LANGUAGE:C>:${COVERAGE_C_LINKER_FLAGS}>)
-        ${scope}
-        $<$<LINK_LANGUAGE:CXX>:${COVERAGE_CXX_LINKER_FLAGS}
-        gcov>
-        $<$<LINK_LANGUAGE:C>:${COVERAGE_C_LINKER_FLAGS}
-        gcov>)
 endfunction () # add_code_coverage_to_target

cmake/XrplCore.cmake

@@ -84,9 +84,6 @@ add_module(xrpl net)
 target_link_libraries(xrpl.libxrpl.net PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.json xrpl.libxrpl.protocol
                                               xrpl.libxrpl.resource)
 
-add_module(xrpl server)
-target_link_libraries(xrpl.libxrpl.server PUBLIC xrpl.libxrpl.protocol)
-
 add_module(xrpl nodestore)
 target_link_libraries(xrpl.libxrpl.nodestore PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.json xrpl.libxrpl.protocol)
 
@@ -94,8 +91,29 @@ add_module(xrpl shamap)
 target_link_libraries(xrpl.libxrpl.shamap PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.crypto xrpl.libxrpl.protocol
                                                  xrpl.libxrpl.nodestore)
 
+add_module(xrpl rdb)
+target_link_libraries(xrpl.libxrpl.rdb PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.core)
+
+add_module(xrpl server)
+target_link_libraries(xrpl.libxrpl.server PUBLIC xrpl.libxrpl.protocol xrpl.libxrpl.core xrpl.libxrpl.rdb
+                                                 xrpl.libxrpl.resource)
+
+add_module(xrpl conditions)
+target_link_libraries(xrpl.libxrpl.conditions PUBLIC xrpl.libxrpl.server)
+
 add_module(xrpl ledger)
-target_link_libraries(xrpl.libxrpl.ledger PUBLIC xrpl.libxrpl.basics xrpl.libxrpl.json xrpl.libxrpl.protocol)
+target_link_libraries(
+    xrpl.libxrpl.ledger
+    PUBLIC xrpl.libxrpl.basics
+           xrpl.libxrpl.json
+           xrpl.libxrpl.protocol
+           xrpl.libxrpl.rdb
+           xrpl.libxrpl.server
+           xrpl.libxrpl.shamap
+           xrpl.libxrpl.conditions)
+
+add_module(xrpl tx)
+target_link_libraries(xrpl.libxrpl.tx PUBLIC xrpl.libxrpl.ledger)
 
 add_library(xrpl.libxrpl)
 set_target_properties(xrpl.libxrpl PROPERTIES OUTPUT_NAME xrpl)
@@ -110,16 +128,19 @@ target_link_modules(
     PUBLIC
     basics
     beast
+    conditions
     core
     crypto
     json
+    ledger
+    net
+    nodestore
     protocol
+    rdb
     resource
     server
-    nodestore
     shamap
-    net
+    tx)
-    ledger)
 
 # All headers in libxrpl are in modules.
 # Uncomment this stanza if you have not yet moved new headers into a module.

cmake/XrplInstall.cmake

@@ -20,9 +20,11 @@ install(TARGETS common
                 xrpl.libxrpl
                 xrpl.libxrpl.basics
                 xrpl.libxrpl.beast
+                xrpl.libxrpl.conditions
                 xrpl.libxrpl.core
                 xrpl.libxrpl.crypto
                 xrpl.libxrpl.json
+                xrpl.libxrpl.rdb
                 xrpl.libxrpl.ledger
                 xrpl.libxrpl.net
                 xrpl.libxrpl.nodestore
@@ -30,6 +32,7 @@ install(TARGETS common
                 xrpl.libxrpl.resource
                 xrpl.libxrpl.server
                 xrpl.libxrpl.shamap
+                xrpl.libxrpl.tx
                 antithesis-sdk-cpp
         EXPORT XrplExports
         LIBRARY DESTINATION lib

docs/CodingStyle.md

@@ -17,8 +17,8 @@ guideline is to maintain the standards that are used in those libraries.
 ## Guidelines
 
 If you want to do something contrary to these guidelines, understand
-why you're doing it. Think, use common sense, and consider that this
+why you're doing it. Think, use common sense, and consider that these
-your changes will probably need to be maintained long after you've
+changes will probably need to be maintained long after you've
 moved on to other projects.
 
 - Use white space and blank lines to guide the eye and keep your intent clear.

include/xrpl/basics/IntrusivePointer.ipp

@@ -208,7 +208,8 @@ SharedIntrusive<T>::operator->() const noexcept
 }
 
 template <class T>
-SharedIntrusive<T>::operator bool() const noexcept
+SharedIntrusive<T>::
+operator bool() const noexcept
 {
     return bool(unsafeGetRawPtr());
 }
@@ -503,7 +504,8 @@ SharedWeakUnion<T>::getStrong() const
 }
 
 template <class T>
-SharedWeakUnion<T>::operator bool() const noexcept
+SharedWeakUnion<T>::
+operator bool() const noexcept
 {
     return bool(get());
 }

include/xrpl/basics/SharedWeakCachePointer.ipp

@@ -63,7 +63,8 @@ SharedWeakCachePointer<T>::getStrong() const
 }
 
 template <class T>
-SharedWeakCachePointer<T>::operator bool() const noexcept
+SharedWeakCachePointer<T>::
+operator bool() const noexcept
 {
     return !!std::get_if<std::shared_ptr<T>>(&combo_);
 }

include/xrpl/basics/SlabAllocator.h

@@ -215,7 +215,7 @@ public:
         // clang-format off
         if (!buf) [[unlikely]]
             return nullptr;
-            // clang-format on
+        // clang-format on
 
 #if BOOST_OS_LINUX
         // When allocating large blocks, attempt to leverage Linux's

include/xrpl/conditions/Condition.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <xrpld/conditions/detail/utils.h>
-
 #include <xrpl/basics/Buffer.h>
 #include <xrpl/basics/Slice.h>
+#include <xrpl/conditions/detail/utils.h>
 
 #include <cstdint>
 #include <set>

include/xrpl/conditions/Fulfillment.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <xrpld/conditions/Condition.h>
-
 #include <xrpl/basics/Buffer.h>
 #include <xrpl/basics/Slice.h>
+#include <xrpl/conditions/Condition.h>
 
 namespace xrpl {
 namespace cryptoconditions {

include/xrpl/conditions/detail/PreimageSha256.h

@@ -1,11 +1,10 @@
 #pragma once
 
-#include <xrpld/conditions/Condition.h>
-#include <xrpld/conditions/Fulfillment.h>
-#include <xrpld/conditions/detail/error.h>
-
 #include <xrpl/basics/Buffer.h>
 #include <xrpl/basics/Slice.h>
+#include <xrpl/conditions/Condition.h>
+#include <xrpl/conditions/Fulfillment.h>
+#include <xrpl/conditions/detail/error.h>
 #include <xrpl/protocol/digest.h>
 
 #include <memory>

include/xrpl/conditions/detail/utils.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <xrpld/conditions/detail/error.h>
-
 #include <xrpl/basics/Buffer.h>
 #include <xrpl/basics/Slice.h>
+#include <xrpl/conditions/detail/error.h>
 
 #include <boost/dynamic_bitset.hpp>
 

include/xrpl/core/HashRouter.h

@@ -251,7 +251,4 @@ private:
     beast::aged_unordered_map<uint256, Entry, Stopwatch::clock_type, hardened_hash<strong_hash>> suppressionMap_;
 };
 
-HashRouter::Setup
-setup_HashRouter(Config const&);
-
 }  // namespace xrpl

include/xrpl/core/NetworkIDService.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <cstdint>
+
+namespace xrpl {
+
+/** Service that provides access to the network ID.
+
+    This service provides read-only access to the network ID configured
+    for this server. The network ID identifies which network (mainnet,
+    testnet, devnet, or custom network) this server is configured to
+    connect to.
+
+    Well-known network IDs:
+    - 0: Mainnet
+    - 1: Testnet
+    - 2: Devnet
+    - 1025+: Custom networks (require NetworkID field in transactions)
+*/
+class NetworkIDService
+{
+public:
+    virtual ~NetworkIDService() = default;
+
+    /** Get the configured network ID
+     *
+     * @return The network ID this server is configured for
+     */
+    virtual std::uint32_t
+    getNetworkID() const noexcept = 0;
+};
+
+}  // namespace xrpl

include/xrpl/core/ServiceRegistry.h

@@ -5,6 +5,8 @@
 #include <xrpl/basics/TaggedCache.h>
 #include <xrpl/ledger/CachedSLEs.h>
 
+#include <boost/asio.hpp>
+
 namespace xrpl {
 
 // Forward declarations
@@ -18,6 +20,10 @@ namespace perf {
 class PerfLog;
 }
 
+// This is temporary until we migrate all code to use ServiceRegistry.
+class Application;
+
+// Forward declarations
 class AcceptedLedger;
 class AmendmentTable;
 class Cluster;
@@ -35,6 +41,7 @@ class LoadFeeTrack;
 class LoadManager;
 class ManifestCache;
 class NetworkOPs;
+class NetworkIDService;
 class OpenLedger;
 class OrderBookDB;
 class Overlay;
@@ -93,6 +100,9 @@ public:
     virtual CachedSLEs&
     cachedSLEs() = 0;
 
+    virtual NetworkIDService&
+    getNetworkIDService() = 0;
+
     // Protocol and validation services
     virtual AmendmentTable&
     getAmendmentTable() = 0;
@@ -194,6 +204,31 @@ public:
 
     virtual perf::PerfLog&
     getPerfLog() = 0;
+
+    // Configuration and state
+    virtual bool
+    isStopping() const = 0;
+
+    virtual beast::Journal
+    journal(std::string const& name) = 0;
+
+    virtual boost::asio::io_context&
+    getIOContext() = 0;
+
+    virtual Logs&
+    logs() = 0;
+
+    virtual std::optional<uint256> const&
+    trapTxID() const = 0;
+
+    /** Retrieve the "wallet database" */
+    virtual DatabaseCon&
+    getWalletDB() = 0;
+
+    // Temporary: Get the underlying Application for functions that haven't
+    // been migrated yet. This should be removed once all code is migrated.
+    virtual Application&
+    app() = 0;
 };
 
 }  // namespace xrpl

include/xrpl/core/StartUpType.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <iosfwd>
+#include <type_traits>
+
+namespace xrpl {
+
+enum class StartUpType { FRESH, NORMAL, LOAD, LOAD_FILE, REPLAY, NETWORK };
+
+inline std::ostream&
+operator<<(std::ostream& os, StartUpType const& type)
+{
+    return os << static_cast<std::underlying_type_t<StartUpType>>(type);
+}
+
+}  // namespace xrpl

include/xrpl/ledger/AcceptedLedgerTx.h

@@ -1,15 +1,15 @@
 #pragma once
 
-#include <xrpld/app/ledger/Ledger.h>
+#include <xrpl/basics/CountedObject.h>
-
+#include <xrpl/ledger/ReadView.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/TxMeta.h>
 
 #include <boost/container/flat_set.hpp>
 
 namespace xrpl {
 
-class Logs;
-
 /**
     A transaction that is in a closed ledger.
 

include/xrpl/ledger/AmendmentTable.h

@@ -1,16 +1,18 @@
 #pragma once
 
-#include <xrpld/app/ledger/Ledger.h>
+#include <xrpl/ledger/ReadView.h>
-#include <xrpld/core/ConfigSections.h>
+#include <xrpl/ledger/View.h>
-
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/STValidation.h>
+#include <xrpl/shamap/SHAMap.h>
 
 #include <optional>
 
 namespace xrpl {
 
+class ServiceRegistry;
+
 /** The amendment table stores the list of enabled and potential amendments.
     Individuals amendments are voted on by validators during the consensus
     process.
@@ -163,7 +165,7 @@ public:
 
 std::unique_ptr<AmendmentTable>
 make_AmendmentTable(
-    Application& app,
+    ServiceRegistry& registry,
     std::chrono::seconds majorityTime,
     std::vector<AmendmentTable::FeatureInfo> const& supported,
     Section const& enabled,

include/xrpl/ledger/BookListeners.h

@@ -1,8 +1,7 @@
 #pragma once
 
-#include <xrpld/rpc/InfoSub.h>
-
 #include <xrpl/protocol/MultiApiJson.h>
+#include <xrpl/server/InfoSub.h>
 
 #include <memory>
 #include <mutex>

include/xrpl/ledger/OrderBookDB.h

@@ -0,0 +1,93 @@
+#pragma once
+
+#include <xrpl/ledger/AcceptedLedgerTx.h>
+#include <xrpl/ledger/BookListeners.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Book.h>
+#include <xrpl/protocol/Issue.h>
+#include <xrpl/protocol/MultiApiJson.h>
+#include <xrpl/protocol/UintTypes.h>
+
+#include <memory>
+#include <optional>
+#include <vector>
+
+namespace xrpl {
+
+/** Tracks order books in the ledger.
+
+    This interface provides access to order book information, including:
+    - Which order books exist in the ledger
+    - Querying order books by issue
+    - Managing order book subscriptions
+
+    The order book database is updated as ledgers are accepted and provides
+    efficient lookup of order book information for pathfinding and client
+    subscriptions.
+*/
+class OrderBookDB
+{
+public:
+    virtual ~OrderBookDB() = default;
+
+    /** Initialize or update the order book database with a new ledger.
+
+        This method should be called when a new ledger is accepted to update
+        the order book database with the current state of all order books.
+
+        @param ledger The ledger to scan for order books
+    */
+    virtual void
+    setup(std::shared_ptr<ReadView const> const& ledger) = 0;
+
+    /** Add an order book to track.
+
+        @param book The order book to add
+    */
+    virtual void
+    addOrderBook(Book const& book) = 0;
+
+    /** Get all order books that want a specific issue.
+
+        Returns a list of all order books where the taker pays the specified
+        issue. This is useful for pathfinding to find all possible next hops
+        from a given currency.
+
+        @param issue The issue to search for
+        @param domain Optional domain restriction for the order book
+        @return Vector of books that want this issue
+    */
+    virtual std::vector<Book>
+    getBooksByTakerPays(Issue const& issue, std::optional<Domain> const& domain = std::nullopt) = 0;
+
+    /** Get the count of order books that want a specific issue.
+
+        @param issue The issue to search for
+        @param domain Optional domain restriction for the order book
+        @return Number of books that want this issue
+    */
+    virtual int
+    getBookSize(Issue const& issue, std::optional<Domain> const& domain = std::nullopt) = 0;
+
+    /** Check if an order book to XRP exists for the given issue.
+
+        @param issue The issue to check
+        @param domain Optional domain restriction for the order book
+        @return true if a book from this issue to XRP exists
+    */
+    virtual bool
+    isBookToXRP(Issue const& issue, std::optional<Domain> domain = std::nullopt) = 0;
+
+    virtual void
+    processTxn(
+        std::shared_ptr<ReadView const> const& ledger,
+        AcceptedLedgerTx const& alTx,
+        MultiApiJson const& jvObj) = 0;
+
+    virtual BookListeners::pointer
+    getBookListeners(Book const&) = 0;
+    virtual BookListeners::pointer
+    makeBookListeners(Book const&) = 0;
+};
+
+}  // namespace xrpl

include/xrpl/protocol/Feature.h

@@ -296,7 +296,7 @@ public:
     friend FeatureBitset
     operator^(FeatureBitset const& lhs, uint256 const& rhs)
     {
-        return lhs ^ FeatureBitset { rhs };
+        return lhs ^ FeatureBitset{rhs};
     }
 
     friend FeatureBitset

include/xrpl/protocol/IOUAmount.h

@@ -110,7 +110,8 @@ IOUAmount::operator=(beast::Zero)
     return *this;
 }
 
-inline IOUAmount::operator Number() const
+inline IOUAmount::
+operator Number() const
 {
     return Number{mantissa_, exponent_};
 }
@@ -140,7 +141,8 @@ IOUAmount::operator<(IOUAmount const& other) const
     return Number{*this} < Number{other};
 }
 
-inline IOUAmount::operator bool() const noexcept
+inline IOUAmount::
+operator bool() const noexcept
 {
     return mantissa_ != 0;
 }

include/xrpl/protocol/LedgerShortcut.h

@@ -0,0 +1,22 @@
+#pragma once
+
+namespace xrpl {
+
+/**
+ * @brief Enumeration of ledger shortcuts for specifying which ledger to use.
+ *
+ * These shortcuts provide a convenient way to reference commonly used ledgers
+ * without needing to specify their exact hash or sequence number.
+ */
+enum class LedgerShortcut {
+    /** The current working ledger (open, not yet closed) */
+    Current,
+
+    /** The most recently closed ledger (may not be validated) */
+    Closed,
+
+    /** The most recently validated ledger */
+    Validated
+};
+
+}  // namespace xrpl

include/xrpl/protocol/MPTAmount.h

@@ -93,7 +93,8 @@ MPTAmount::operator=(beast::Zero)
 }
 
 /** Returns true if the amount is not zero */
-constexpr MPTAmount::operator bool() const noexcept
+constexpr MPTAmount::
+operator bool() const noexcept
 {
     return value_ != 0;
 }

include/xrpl/protocol/MultiApiJson.h

@@ -107,7 +107,7 @@ struct MultiApiJson
         // unsigned int version, extra arguments
         template <typename Json, typename Version, typename... Args, typename Fn>
             requires(!some_integral_constant<Version>) && std::convertible_to<Version, unsigned> &&
-                        std::same_as<std::remove_cvref_t<Json>, MultiApiJson>
+            std::same_as<std::remove_cvref_t<Json>, MultiApiJson>
         auto
         operator()(Json& json, Version version, Fn fn, Args&&... args) const
             -> std::invoke_result_t<Fn, decltype(json.val[0]), Version, Args&&...>
@@ -122,7 +122,7 @@ struct MultiApiJson
         // unsigned int version, Json only
         template <typename Json, typename Version, typename Fn>
             requires(!some_integral_constant<Version>) && std::convertible_to<Version, unsigned> &&
-                        std::same_as<std::remove_cvref_t<Json>, MultiApiJson>
+            std::same_as<std::remove_cvref_t<Json>, MultiApiJson>
         auto
         operator()(Json& json, Version version, Fn fn) const -> std::invoke_result_t<Fn, decltype(json.val[0])>
         {

include/xrpl/protocol/Protocol.h

@@ -253,6 +253,16 @@ std::uint8_t constexpr maxAssetCheckDepth = 5;
 /** A ledger index. */
 using LedgerIndex = std::uint32_t;
 
+std::uint32_t constexpr FLAG_LEDGER_INTERVAL = 256;
+
+/** Returns true if the given ledgerIndex is a voting ledgerIndex */
+bool
+isVotingLedger(LedgerIndex seq);
+
+/** Returns true if the given ledgerIndex is a flag ledgerIndex */
+bool
+isFlagLedger(LedgerIndex seq);
+
 /** A transaction identifier.
     The value is computed as the hash of the
     canonicalized, serialized transaction object.

include/xrpl/protocol/STAmount.h

@@ -480,12 +480,14 @@ STAmount::zeroed() const
     return STAmount(mAsset);
 }
 
-inline STAmount::operator bool() const noexcept
+inline STAmount::
+operator bool() const noexcept
 {
     return *this != beast::zero;
 }
 
-inline STAmount::operator Number() const
+inline STAmount::
+operator Number() const
 {
     if (native())
         return xrp();

include/xrpl/protocol/STBitString.h

@@ -169,7 +169,8 @@ STBitString<Bits>::value() const
 }
 
 template <int Bits>
-STBitString<Bits>::operator value_type() const
+STBitString<Bits>::
+operator value_type() const
 {
     return value_;
 }

include/xrpl/protocol/STInteger.h

@@ -134,7 +134,8 @@ STInteger<Integer>::setValue(Integer v)
 }
 
 template <typename Integer>
-inline STInteger<Integer>::operator Integer() const
+inline STInteger<Integer>::
+operator Integer() const
 {
     return value_;
 }

include/xrpl/protocol/STObject.h

@@ -147,9 +147,12 @@ public:
     int
     getCount() const;
 
-    bool setFlag(std::uint32_t);
+    bool
-    bool clearFlag(std::uint32_t);
+    setFlag(std::uint32_t);
-    bool isFlag(std::uint32_t) const;
+    bool
+    clearFlag(std::uint32_t);
+    bool
+    isFlag(std::uint32_t) const;
 
     std::uint32_t
     getFlags() const;
@@ -799,7 +802,8 @@ STObject::ValueProxy<T>::operator-=(U const& u)
 }
 
 template <class T>
-STObject::ValueProxy<T>::operator value_type() const
+STObject::ValueProxy<T>::
+operator value_type() const
 {
     return this->value();
 }
@@ -812,13 +816,15 @@ STObject::ValueProxy<T>::ValueProxy(STObject* st, TypedField<T> const* f) : Prox
 //------------------------------------------------------------------------------
 
 template <class T>
-STObject::OptionalProxy<T>::operator bool() const noexcept
+STObject::OptionalProxy<T>::
+operator bool() const noexcept
 {
     return engaged();
 }
 
 template <class T>
-STObject::OptionalProxy<T>::operator typename STObject::OptionalProxy<T>::optional_type() const
+STObject::OptionalProxy<T>::
+operator typename STObject::OptionalProxy<T>::optional_type() const
 {
     return optional_value();
 }

include/xrpl/protocol/STVector256.h

@@ -135,7 +135,8 @@ STVector256::setValue(STVector256 const& v)
 }
 
 /** Retrieve a copy of the vector we contain */
-inline STVector256::operator std::vector<uint256>() const
+inline STVector256::
+operator std::vector<uint256>() const
 {
     return mValue;
 }

include/xrpl/protocol/TER.h

@@ -484,60 +484,54 @@ public:
 // Only enabled if both arguments return int if TERtiInt is called with them.
 template <typename L, typename R>
 constexpr auto
-operator==(L const& lhs, R const& rhs)
+operator==(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) == TERtoInt(rhs);
 }
 
 template <typename L, typename R>
 constexpr auto
-operator!=(L const& lhs, R const& rhs)
+operator!=(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) != TERtoInt(rhs);
 }
 
 template <typename L, typename R>
 constexpr auto
-operator<(L const& lhs, R const& rhs)
+operator<(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) < TERtoInt(rhs);
 }
 
 template <typename L, typename R>
 constexpr auto
-operator<=(L const& lhs, R const& rhs)
+operator<=(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) <= TERtoInt(rhs);
 }
 
 template <typename L, typename R>
 constexpr auto
-operator>(L const& lhs, R const& rhs)
+operator>(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) > TERtoInt(rhs);
 }
 
 template <typename L, typename R>
 constexpr auto
-operator>=(L const& lhs, R const& rhs)
+operator>=(L const& lhs, R const& rhs) -> std::enable_if_t<
-    -> std::enable_if_t<
+    std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
-        std::is_same<decltype(TERtoInt(lhs)), int>::value && std::is_same<decltype(TERtoInt(rhs)), int>::value,
+    bool>
-        bool>
 {
     return TERtoInt(lhs) >= TERtoInt(rhs);
 }

include/xrpl/protocol/TxSearched.h

@@ -0,0 +1,7 @@
+#pragma once
+
+namespace xrpl {
+
+enum class TxSearched { all, some, unknown };
+
+}

include/xrpl/protocol/detail/transactions.macro

@@ -8,11 +8,11 @@
  * To ease maintenance, you may replace any unneeded values with "..."
  * e.g. #define TRANSACTION(tag, value, name, ...)
  *
- * You must define a transactor class in the `ripple` namespace named `name`,
+ * You must define a transactor class in the `xrpl` namespace named `name`,
  * and include its header alongside the TRANSACTOR definition using this
  * format:
  * #if TRANSACTION_INCLUDE
- * #   include <xrpld/app/tx/detail/HEADER.h>
+ * #   include <xrpl/tx/transactors/HEADER.h>
  * #endif
  *
  * The `privileges` parameter of the TRANSACTION macro is a bitfield
@@ -22,7 +22,7 @@
 
 /** This transaction type executes a payment. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Payment.h>
+#   include <xrpl/tx/transactors/Payment.h>
 #endif
 TRANSACTION(ttPAYMENT, 0, Payment,
     Delegation::delegable,
@@ -42,7 +42,7 @@ TRANSACTION(ttPAYMENT, 0, Payment,
 
 /** This transaction type creates an escrow object. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Escrow.h>
+#   include <xrpl/tx/transactors/Escrow.h>
 #endif
 TRANSACTION(ttESCROW_CREATE, 1, EscrowCreate,
     Delegation::delegable,
@@ -73,7 +73,7 @@ TRANSACTION(ttESCROW_FINISH, 2, EscrowFinish,
 
 /** This transaction type adjusts various account settings. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/SetAccount.h>
+#   include <xrpl/tx/transactors/SetAccount.h>
 #endif
 TRANSACTION(ttACCOUNT_SET, 3, AccountSet,
     Delegation::notDelegable,
@@ -94,7 +94,7 @@ TRANSACTION(ttACCOUNT_SET, 3, AccountSet,
 
 /** This transaction type cancels an existing escrow. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Escrow.h>
+#   include <xrpl/tx/transactors/Escrow.h>
 #endif
 TRANSACTION(ttESCROW_CANCEL, 4, EscrowCancel,
     Delegation::delegable,
@@ -107,7 +107,7 @@ TRANSACTION(ttESCROW_CANCEL, 4, EscrowCancel,
 
 /** This transaction type sets or clears an account's "regular key". */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/SetRegularKey.h>
+#   include <xrpl/tx/transactors/SetRegularKey.h>
 #endif
 TRANSACTION(ttREGULAR_KEY_SET, 5, SetRegularKey,
     Delegation::notDelegable,
@@ -121,7 +121,7 @@ TRANSACTION(ttREGULAR_KEY_SET, 5, SetRegularKey,
 
 /** This transaction type creates an offer to trade one asset for another. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CreateOffer.h>
+#   include <xrpl/tx/transactors/Offer/CreateOffer.h>
 #endif
 TRANSACTION(ttOFFER_CREATE, 7, OfferCreate,
     Delegation::delegable,
@@ -137,7 +137,7 @@ TRANSACTION(ttOFFER_CREATE, 7, OfferCreate,
 
 /** This transaction type cancels existing offers to trade one asset for another. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CancelOffer.h>
+#   include <xrpl/tx/transactors/Offer/CancelOffer.h>
 #endif
 TRANSACTION(ttOFFER_CANCEL, 8, OfferCancel,
     Delegation::delegable,
@@ -151,7 +151,7 @@ TRANSACTION(ttOFFER_CANCEL, 8, OfferCancel,
 
 /** This transaction type creates a new set of tickets. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CreateTicket.h>
+#   include <xrpl/tx/transactors/CreateTicket.h>
 #endif
 TRANSACTION(ttTICKET_CREATE, 10, TicketCreate,
     Delegation::delegable,
@@ -167,7 +167,7 @@ TRANSACTION(ttTICKET_CREATE, 10, TicketCreate,
 // The SignerEntries are optional because a SignerList is deleted by
 // setting the SignerQuorum to zero and omitting SignerEntries.
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/SetSignerList.h>
+#   include <xrpl/tx/transactors/SetSignerList.h>
 #endif
 TRANSACTION(ttSIGNER_LIST_SET, 12, SignerListSet,
     Delegation::notDelegable,
@@ -180,7 +180,7 @@ TRANSACTION(ttSIGNER_LIST_SET, 12, SignerListSet,
 
 /** This transaction type creates a new unidirectional XRP payment channel. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/PayChan.h>
+#   include <xrpl/tx/transactors/PayChan.h>
 #endif
 TRANSACTION(ttPAYCHAN_CREATE, 13, PaymentChannelCreate,
     Delegation::delegable,
@@ -222,7 +222,7 @@ TRANSACTION(ttPAYCHAN_CLAIM, 15, PaymentChannelClaim,
 
 /** This transaction type creates a new check. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CreateCheck.h>
+#   include <xrpl/tx/transactors/Check/CreateCheck.h>
 #endif
 TRANSACTION(ttCHECK_CREATE, 16, CheckCreate,
     Delegation::delegable,
@@ -238,7 +238,7 @@ TRANSACTION(ttCHECK_CREATE, 16, CheckCreate,
 
 /** This transaction type cashes an existing check. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CashCheck.h>
+#   include <xrpl/tx/transactors/Check/CashCheck.h>
 #endif
 TRANSACTION(ttCHECK_CASH, 17, CheckCash,
     Delegation::delegable,
@@ -252,7 +252,7 @@ TRANSACTION(ttCHECK_CASH, 17, CheckCash,
 
 /** This transaction type cancels an existing check. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/CancelCheck.h>
+#   include <xrpl/tx/transactors/Check/CancelCheck.h>
 #endif
 TRANSACTION(ttCHECK_CANCEL, 18, CheckCancel,
     Delegation::delegable,
@@ -264,7 +264,7 @@ TRANSACTION(ttCHECK_CANCEL, 18, CheckCancel,
 
 /** This transaction type grants or revokes authorization to transfer funds. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/DepositPreauth.h>
+#   include <xrpl/tx/transactors/DepositPreauth.h>
 #endif
 TRANSACTION(ttDEPOSIT_PREAUTH, 19, DepositPreauth,
     Delegation::delegable,
@@ -279,7 +279,7 @@ TRANSACTION(ttDEPOSIT_PREAUTH, 19, DepositPreauth,
 
 /** This transaction type modifies a trustline between two accounts. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/SetTrust.h>
+#   include <xrpl/tx/transactors/SetTrust.h>
 #endif
 TRANSACTION(ttTRUST_SET, 20, TrustSet,
     Delegation::delegable,
@@ -293,7 +293,7 @@ TRANSACTION(ttTRUST_SET, 20, TrustSet,
 
 /** This transaction type deletes an existing account. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/DeleteAccount.h>
+#   include <xrpl/tx/transactors/DeleteAccount.h>
 #endif
 TRANSACTION(ttACCOUNT_DELETE, 21, AccountDelete,
     Delegation::notDelegable,
@@ -309,7 +309,7 @@ TRANSACTION(ttACCOUNT_DELETE, 21, AccountDelete,
 
 /** This transaction mints a new NFT. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenMint.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenMint.h>
 #endif
 TRANSACTION(ttNFTOKEN_MINT, 25, NFTokenMint,
     Delegation::delegable,
@@ -327,7 +327,7 @@ TRANSACTION(ttNFTOKEN_MINT, 25, NFTokenMint,
 
 /** This transaction burns (i.e. destroys) an existing NFT. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenBurn.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenBurn.h>
 #endif
 TRANSACTION(ttNFTOKEN_BURN, 26, NFTokenBurn,
     Delegation::delegable,
@@ -340,7 +340,7 @@ TRANSACTION(ttNFTOKEN_BURN, 26, NFTokenBurn,
 
 /** This transaction creates a new offer to buy or sell an NFT. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenCreateOffer.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenCreateOffer.h>
 #endif
 TRANSACTION(ttNFTOKEN_CREATE_OFFER, 27, NFTokenCreateOffer,
     Delegation::delegable,
@@ -356,7 +356,7 @@ TRANSACTION(ttNFTOKEN_CREATE_OFFER, 27, NFTokenCreateOffer,
 
 /** This transaction cancels an existing offer to buy or sell an existing NFT. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenCancelOffer.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenCancelOffer.h>
 #endif
 TRANSACTION(ttNFTOKEN_CANCEL_OFFER, 28, NFTokenCancelOffer,
     Delegation::delegable,
@@ -368,7 +368,7 @@ TRANSACTION(ttNFTOKEN_CANCEL_OFFER, 28, NFTokenCancelOffer,
 
 /** This transaction accepts an existing offer to buy or sell an existing  NFT. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenAcceptOffer.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenAcceptOffer.h>
 #endif
 TRANSACTION(ttNFTOKEN_ACCEPT_OFFER, 29, NFTokenAcceptOffer,
     Delegation::delegable,
@@ -382,7 +382,7 @@ TRANSACTION(ttNFTOKEN_ACCEPT_OFFER, 29, NFTokenAcceptOffer,
 
 /** This transaction claws back issued tokens. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Clawback.h>
+#   include <xrpl/tx/transactors/Clawback.h>
 #endif
 TRANSACTION(ttCLAWBACK, 30, Clawback,
     Delegation::delegable,
@@ -395,7 +395,7 @@ TRANSACTION(ttCLAWBACK, 30, Clawback,
 
 /** This transaction claws back tokens from an AMM pool. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMClawback.h>
+#   include <xrpl/tx/transactors/AMM/AMMClawback.h>
 #endif
 TRANSACTION(ttAMM_CLAWBACK, 31, AMMClawback,
     Delegation::delegable,
@@ -410,7 +410,7 @@ TRANSACTION(ttAMM_CLAWBACK, 31, AMMClawback,
 
 /** This transaction type creates an AMM instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMCreate.h>
+#   include <xrpl/tx/transactors/AMM/AMMCreate.h>
 #endif
 TRANSACTION(ttAMM_CREATE, 35, AMMCreate,
     Delegation::delegable,
@@ -424,7 +424,7 @@ TRANSACTION(ttAMM_CREATE, 35, AMMCreate,
 
 /** This transaction type deposits into an AMM instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMDeposit.h>
+#   include <xrpl/tx/transactors/AMM/AMMDeposit.h>
 #endif
 TRANSACTION(ttAMM_DEPOSIT, 36, AMMDeposit,
     Delegation::delegable,
@@ -442,7 +442,7 @@ TRANSACTION(ttAMM_DEPOSIT, 36, AMMDeposit,
 
 /** This transaction type withdraws from an AMM instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMWithdraw.h>
+#   include <xrpl/tx/transactors/AMM/AMMWithdraw.h>
 #endif
 TRANSACTION(ttAMM_WITHDRAW, 37, AMMWithdraw,
     Delegation::delegable,
@@ -459,7 +459,7 @@ TRANSACTION(ttAMM_WITHDRAW, 37, AMMWithdraw,
 
 /** This transaction type votes for the trading fee */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMVote.h>
+#   include <xrpl/tx/transactors/AMM/AMMVote.h>
 #endif
 TRANSACTION(ttAMM_VOTE, 38, AMMVote,
     Delegation::delegable,
@@ -473,7 +473,7 @@ TRANSACTION(ttAMM_VOTE, 38, AMMVote,
 
 /** This transaction type bids for the auction slot */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMBid.h>
+#   include <xrpl/tx/transactors/AMM/AMMBid.h>
 #endif
 TRANSACTION(ttAMM_BID, 39, AMMBid,
     Delegation::delegable,
@@ -489,7 +489,7 @@ TRANSACTION(ttAMM_BID, 39, AMMBid,
 
 /** This transaction type deletes AMM in the empty state */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/AMMDelete.h>
+#   include <xrpl/tx/transactors/AMM/AMMDelete.h>
 #endif
 TRANSACTION(ttAMM_DELETE, 40, AMMDelete,
     Delegation::delegable,
@@ -502,7 +502,7 @@ TRANSACTION(ttAMM_DELETE, 40, AMMDelete,
 
 /** This transactions creates a crosschain sequence number */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/XChainBridge.h>
+#   include <xrpl/tx/transactors/XChainBridge.h>
 #endif
 TRANSACTION(ttXCHAIN_CREATE_CLAIM_ID, 41, XChainCreateClaimID,
     Delegation::delegable,
@@ -617,7 +617,7 @@ TRANSACTION(ttXCHAIN_CREATE_BRIDGE, 48, XChainCreateBridge,
 
 /** This transaction type creates or updates a DID */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/DID.h>
+#   include <xrpl/tx/transactors/DID.h>
 #endif
 TRANSACTION(ttDID_SET, 49, DIDSet,
     Delegation::delegable,
@@ -638,7 +638,7 @@ TRANSACTION(ttDID_DELETE, 50, DIDDelete,
 
 /** This transaction type creates an Oracle instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/SetOracle.h>
+#   include <xrpl/tx/transactors/SetOracle.h>
 #endif
 TRANSACTION(ttORACLE_SET, 51, OracleSet,
     Delegation::delegable,
@@ -655,7 +655,7 @@ TRANSACTION(ttORACLE_SET, 51, OracleSet,
 
 /** This transaction type deletes an Oracle instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/DeleteOracle.h>
+#   include <xrpl/tx/transactors/DeleteOracle.h>
 #endif
 TRANSACTION(ttORACLE_DELETE, 52, OracleDelete,
     Delegation::delegable,
@@ -667,7 +667,7 @@ TRANSACTION(ttORACLE_DELETE, 52, OracleDelete,
 
 /** This transaction type fixes a problem in the ledger state */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LedgerStateFix.h>
+#   include <xrpl/tx/transactors/LedgerStateFix.h>
 #endif
 TRANSACTION(ttLEDGER_STATE_FIX, 53, LedgerStateFix,
     Delegation::delegable,
@@ -680,7 +680,7 @@ TRANSACTION(ttLEDGER_STATE_FIX, 53, LedgerStateFix,
 
 /** This transaction type creates a MPTokensIssuance instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/MPTokenIssuanceCreate.h>
+#   include <xrpl/tx/transactors/MPT/MPTokenIssuanceCreate.h>
 #endif
 TRANSACTION(ttMPTOKEN_ISSUANCE_CREATE, 54, MPTokenIssuanceCreate,
     Delegation::delegable,
@@ -697,7 +697,7 @@ TRANSACTION(ttMPTOKEN_ISSUANCE_CREATE, 54, MPTokenIssuanceCreate,
 
 /** This transaction type destroys a MPTokensIssuance instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/MPTokenIssuanceDestroy.h>
+#   include <xrpl/tx/transactors/MPT/MPTokenIssuanceDestroy.h>
 #endif
 TRANSACTION(ttMPTOKEN_ISSUANCE_DESTROY, 55, MPTokenIssuanceDestroy,
     Delegation::delegable,
@@ -709,7 +709,7 @@ TRANSACTION(ttMPTOKEN_ISSUANCE_DESTROY, 55, MPTokenIssuanceDestroy,
 
 /** This transaction type sets flags on a MPTokensIssuance or MPToken instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/MPTokenIssuanceSet.h>
+#   include <xrpl/tx/transactors/MPT/MPTokenIssuanceSet.h>
 #endif
 TRANSACTION(ttMPTOKEN_ISSUANCE_SET, 56, MPTokenIssuanceSet,
     Delegation::delegable,
@@ -726,7 +726,7 @@ TRANSACTION(ttMPTOKEN_ISSUANCE_SET, 56, MPTokenIssuanceSet,
 
 /** This transaction type authorizes a MPToken instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/MPTokenAuthorize.h>
+#   include <xrpl/tx/transactors/MPT/MPTokenAuthorize.h>
 #endif
 TRANSACTION(ttMPTOKEN_AUTHORIZE, 57, MPTokenAuthorize,
     Delegation::delegable,
@@ -739,7 +739,7 @@ TRANSACTION(ttMPTOKEN_AUTHORIZE, 57, MPTokenAuthorize,
 
 /** This transaction type create an Credential instance */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Credentials.h>
+#   include <xrpl/tx/transactors/Credentials.h>
 #endif
 TRANSACTION(ttCREDENTIAL_CREATE, 58, CredentialCreate,
     Delegation::delegable,
@@ -775,7 +775,7 @@ TRANSACTION(ttCREDENTIAL_DELETE, 60, CredentialDelete,
 
 /** This transaction type modify a NFToken */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/NFTokenModify.h>
+#   include <xrpl/tx/transactors/NFT/NFTokenModify.h>
 #endif
 TRANSACTION(ttNFTOKEN_MODIFY, 61, NFTokenModify,
     Delegation::delegable,
@@ -789,7 +789,7 @@ TRANSACTION(ttNFTOKEN_MODIFY, 61, NFTokenModify,
 
 /** This transaction type creates or modifies a Permissioned Domain */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/PermissionedDomainSet.h>
+#   include <xrpl/tx/transactors/PermissionedDomain/PermissionedDomainSet.h>
 #endif
 TRANSACTION(ttPERMISSIONED_DOMAIN_SET, 62, PermissionedDomainSet,
     Delegation::delegable,
@@ -802,7 +802,7 @@ TRANSACTION(ttPERMISSIONED_DOMAIN_SET, 62, PermissionedDomainSet,
 
 /** This transaction type deletes a Permissioned Domain */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/PermissionedDomainDelete.h>
+#   include <xrpl/tx/transactors/PermissionedDomain/PermissionedDomainDelete.h>
 #endif
 TRANSACTION(ttPERMISSIONED_DOMAIN_DELETE, 63, PermissionedDomainDelete,
     Delegation::delegable,
@@ -814,7 +814,7 @@ TRANSACTION(ttPERMISSIONED_DOMAIN_DELETE, 63, PermissionedDomainDelete,
 
 /** This transaction type delegates authorized account specified permissions */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/DelegateSet.h>
+#   include <xrpl/tx/transactors/Delegate/DelegateSet.h>
 #endif
 TRANSACTION(ttDELEGATE_SET, 64, DelegateSet,
     Delegation::notDelegable,
@@ -827,7 +827,7 @@ TRANSACTION(ttDELEGATE_SET, 64, DelegateSet,
 
 /** This transaction creates a single asset vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultCreate.h>
+#   include <xrpl/tx/transactors/Vault/VaultCreate.h>
 #endif
 TRANSACTION(ttVAULT_CREATE, 65, VaultCreate,
     Delegation::delegable,
@@ -845,7 +845,7 @@ TRANSACTION(ttVAULT_CREATE, 65, VaultCreate,
 
 /** This transaction updates a single asset vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultSet.h>
+#   include <xrpl/tx/transactors/Vault/VaultSet.h>
 #endif
 TRANSACTION(ttVAULT_SET, 66, VaultSet,
     Delegation::delegable,
@@ -860,7 +860,7 @@ TRANSACTION(ttVAULT_SET, 66, VaultSet,
 
 /** This transaction deletes a single asset vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultDelete.h>
+#   include <xrpl/tx/transactors/Vault/VaultDelete.h>
 #endif
 TRANSACTION(ttVAULT_DELETE, 67, VaultDelete,
     Delegation::delegable,
@@ -872,7 +872,7 @@ TRANSACTION(ttVAULT_DELETE, 67, VaultDelete,
 
 /** This transaction trades assets for shares with a vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultDeposit.h>
+#   include <xrpl/tx/transactors/Vault/VaultDeposit.h>
 #endif
 TRANSACTION(ttVAULT_DEPOSIT, 68, VaultDeposit,
     Delegation::delegable,
@@ -885,7 +885,7 @@ TRANSACTION(ttVAULT_DEPOSIT, 68, VaultDeposit,
 
 /** This transaction trades shares for assets with a vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultWithdraw.h>
+#   include <xrpl/tx/transactors/Vault/VaultWithdraw.h>
 #endif
 TRANSACTION(ttVAULT_WITHDRAW, 69, VaultWithdraw,
     Delegation::delegable,
@@ -900,7 +900,7 @@ TRANSACTION(ttVAULT_WITHDRAW, 69, VaultWithdraw,
 
 /** This transaction claws back tokens from a vault. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/VaultClawback.h>
+#   include <xrpl/tx/transactors/Vault/VaultClawback.h>
 #endif
 TRANSACTION(ttVAULT_CLAWBACK, 70, VaultClawback,
     Delegation::delegable,
@@ -914,7 +914,7 @@ TRANSACTION(ttVAULT_CLAWBACK, 70, VaultClawback,
 
 /** This transaction type batches together transactions. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Batch.h>
+#   include <xrpl/tx/transactors/Batch.h>
 #endif
 TRANSACTION(ttBATCH, 71, Batch,
     Delegation::notDelegable,
@@ -929,7 +929,7 @@ TRANSACTION(ttBATCH, 71, Batch,
 
 /** This transaction creates and updates a Loan Broker */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanBrokerSet.h>
+#   include <xrpl/tx/transactors/Lending/LoanBrokerSet.h>
 #endif
 TRANSACTION(ttLOAN_BROKER_SET, 74, LoanBrokerSet,
     Delegation::delegable,
@@ -946,7 +946,7 @@ TRANSACTION(ttLOAN_BROKER_SET, 74, LoanBrokerSet,
 
 /** This transaction deletes a Loan Broker */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanBrokerDelete.h>
+#   include <xrpl/tx/transactors/Lending/LoanBrokerDelete.h>
 #endif
 TRANSACTION(ttLOAN_BROKER_DELETE, 75, LoanBrokerDelete,
     Delegation::delegable,
@@ -957,7 +957,7 @@ TRANSACTION(ttLOAN_BROKER_DELETE, 75, LoanBrokerDelete,
 
 /** This transaction deposits First Loss Capital into a Loan Broker */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanBrokerCoverDeposit.h>
+#   include <xrpl/tx/transactors/Lending/LoanBrokerCoverDeposit.h>
 #endif
 TRANSACTION(ttLOAN_BROKER_COVER_DEPOSIT, 76, LoanBrokerCoverDeposit,
     Delegation::delegable,
@@ -969,7 +969,7 @@ TRANSACTION(ttLOAN_BROKER_COVER_DEPOSIT, 76, LoanBrokerCoverDeposit,
 
 /** This transaction withdraws First Loss Capital from a Loan Broker */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanBrokerCoverWithdraw.h>
+#   include <xrpl/tx/transactors/Lending/LoanBrokerCoverWithdraw.h>
 #endif
 TRANSACTION(ttLOAN_BROKER_COVER_WITHDRAW, 77, LoanBrokerCoverWithdraw,
     Delegation::delegable,
@@ -984,7 +984,7 @@ TRANSACTION(ttLOAN_BROKER_COVER_WITHDRAW, 77, LoanBrokerCoverWithdraw,
 /** This transaction claws back First Loss Capital from a Loan Broker to
     the issuer of the capital */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanBrokerCoverClawback.h>
+#   include <xrpl/tx/transactors/Lending/LoanBrokerCoverClawback.h>
 #endif
 TRANSACTION(ttLOAN_BROKER_COVER_CLAWBACK, 78, LoanBrokerCoverClawback,
     Delegation::delegable,
@@ -996,7 +996,7 @@ TRANSACTION(ttLOAN_BROKER_COVER_CLAWBACK, 78, LoanBrokerCoverClawback,
 
 /** This transaction creates a Loan */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanSet.h>
+#   include <xrpl/tx/transactors/Lending/LoanSet.h>
 #endif
 TRANSACTION(ttLOAN_SET, 80, LoanSet,
     Delegation::delegable,
@@ -1023,7 +1023,7 @@ TRANSACTION(ttLOAN_SET, 80, LoanSet,
 
 /** This transaction deletes an existing Loan */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanDelete.h>
+#   include <xrpl/tx/transactors/Lending/LoanDelete.h>
 #endif
 TRANSACTION(ttLOAN_DELETE, 81, LoanDelete,
     Delegation::delegable,
@@ -1034,7 +1034,7 @@ TRANSACTION(ttLOAN_DELETE, 81, LoanDelete,
 
 /** This transaction is used to change the delinquency status of an existing Loan */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanManage.h>
+#   include <xrpl/tx/transactors/Lending/LoanManage.h>
 #endif
 TRANSACTION(ttLOAN_MANAGE, 82, LoanManage,
     Delegation::delegable,
@@ -1048,7 +1048,7 @@ TRANSACTION(ttLOAN_MANAGE, 82, LoanManage,
 
 /** The Borrower uses this transaction to make a Payment on the Loan. */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/LoanPay.h>
+#   include <xrpl/tx/transactors/Lending/LoanPay.h>
 #endif
 TRANSACTION(ttLOAN_PAY, 84, LoanPay,
     Delegation::delegable,
@@ -1063,7 +1063,7 @@ TRANSACTION(ttLOAN_PAY, 84, LoanPay,
     For details, see: https://xrpl.org/amendments.html
  */
 #if TRANSACTION_INCLUDE
-#   include <xrpld/app/tx/detail/Change.h>
+#   include <xrpl/tx/transactors/Change.h>
 #endif
 TRANSACTION(ttAMENDMENT, 100, EnableAmendment,
     Delegation::notDelegable,

include/xrpl/rdb/DatabaseCon.h

@@ -1,10 +1,9 @@
 #pragma once
 
-#include <xrpld/app/main/DBInit.h>
-#include <xrpld/core/Config.h>
-#include <xrpld/core/SociDB.h>
-
 #include <xrpl/core/PerfLog.h>
+#include <xrpl/core/StartUpType.h>
+#include <xrpl/rdb/DBInit.h>
+#include <xrpl/rdb/SociDB.h>
 
 #include <boost/filesystem/path.hpp>
 
@@ -68,7 +67,7 @@ public:
     {
         explicit Setup() = default;
 
-        Config::StartUpType startUp = Config::NORMAL;
+        StartUpType startUp = StartUpType::NORMAL;
         bool standAlone = false;
         boost::filesystem::path dataDir;
         // Indicates whether or not to return the `globalPragma`
@@ -105,8 +104,8 @@ public:
         beast::Journal journal)
         // Use temporary files or regular DB files?
         : DatabaseCon(
-              setup.standAlone && setup.startUp != Config::LOAD && setup.startUp != Config::LOAD_FILE &&
+              setup.standAlone && setup.startUp != StartUpType::LOAD && setup.startUp != StartUpType::LOAD_FILE &&
-                      setup.startUp != Config::REPLAY
+                      setup.startUp != StartUpType::REPLAY
                   ? ""
                   : (setup.dataDir / dbName),
               setup.commonPragma(),
@@ -229,7 +228,4 @@ private:
 std::shared_ptr<Checkpointer>
 checkpointerFromId(std::uintptr_t id);
 
-DatabaseCon::Setup
-setup_DatabaseCon(Config const& c, std::optional<beast::Journal> j = std::nullopt);
-
 }  // namespace xrpl

include/xrpl/rdb/RelationalDatabase.h

@@ -0,0 +1,475 @@
+#pragma once
+
+#include <xrpl/basics/RangeSet.h>
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/core/ServiceRegistry.h>
+#include <xrpl/protocol/ErrorCodes.h>
+#include <xrpl/protocol/LedgerHeader.h>
+#include <xrpl/protocol/LedgerShortcut.h>
+#include <xrpl/protocol/TxMeta.h>
+#include <xrpl/protocol/TxSearched.h>
+#include <xrpl/rdb/DatabaseCon.h>
+
+#include <boost/filesystem.hpp>
+#include <boost/variant.hpp>
+
+namespace xrpl {
+
+class Transaction;
+class Ledger;
+
+struct LedgerHashPair
+{
+    uint256 ledgerHash;
+    uint256 parentHash;
+};
+
+struct LedgerRange
+{
+    uint32_t min;
+    uint32_t max;
+};
+
+class RelationalDatabase
+{
+public:
+    struct CountMinMax
+    {
+        std::size_t numberOfRows;
+        LedgerIndex minLedgerSequence;
+        LedgerIndex maxLedgerSequence;
+    };
+
+    struct AccountTxMarker
+    {
+        std::uint32_t ledgerSeq = 0;
+        std::uint32_t txnSeq = 0;
+    };
+
+    struct AccountTxOptions
+    {
+        AccountID const& account;
+        std::uint32_t minLedger;
+        std::uint32_t maxLedger;
+        std::uint32_t offset;
+        std::uint32_t limit;
+        bool bUnlimited;
+    };
+
+    struct AccountTxPageOptions
+    {
+        AccountID const& account;
+        std::uint32_t minLedger;
+        std::uint32_t maxLedger;
+        std::optional<AccountTxMarker> marker;
+        std::uint32_t limit;
+        bool bAdmin;
+    };
+
+    using AccountTx = std::pair<std::shared_ptr<Transaction>, std::shared_ptr<TxMeta>>;
+    using AccountTxs = std::vector<AccountTx>;
+    using txnMetaLedgerType = std::tuple<Blob, Blob, std::uint32_t>;
+    using MetaTxsList = std::vector<txnMetaLedgerType>;
+
+    using LedgerSequence = uint32_t;
+    using LedgerHash = uint256;
+    using LedgerSpecifier = std::variant<LedgerRange, LedgerShortcut, LedgerSequence, LedgerHash>;
+
+    struct AccountTxArgs
+    {
+        AccountID account;
+        std::optional<LedgerSpecifier> ledger;
+        bool binary = false;
+        bool forward = false;
+        uint32_t limit = 0;
+        std::optional<AccountTxMarker> marker;
+    };
+
+    struct AccountTxResult
+    {
+        std::variant<AccountTxs, MetaTxsList> transactions;
+        LedgerRange ledgerRange;
+        uint32_t limit;
+        std::optional<AccountTxMarker> marker;
+    };
+
+    virtual ~RelationalDatabase() = default;
+
+    /**
+     * @brief getMinLedgerSeq Returns the minimum ledger sequence in the Ledgers
+     *        table.
+     * @return Ledger sequence or no value if no ledgers exist.
+     */
+    virtual std::optional<LedgerIndex>
+    getMinLedgerSeq() = 0;
+
+    /**
+     * @brief getMaxLedgerSeq Returns the maximum ledger sequence in the Ledgers
+     *        table.
+     * @return Ledger sequence or none if no ledgers exist.
+     */
+    virtual std::optional<LedgerIndex>
+    getMaxLedgerSeq() = 0;
+
+    /**
+     * @brief getLedgerInfoByIndex Returns a ledger by its sequence.
+     * @param ledgerSeq Ledger sequence.
+     * @return The ledger if found, otherwise no value.
+     */
+    virtual std::optional<LedgerHeader>
+    getLedgerInfoByIndex(LedgerIndex ledgerSeq) = 0;
+
+    /**
+     * @brief getNewestLedgerInfo Returns the info of the newest saved ledger.
+     * @return Ledger info if found, otherwise no value.
+     */
+    virtual std::optional<LedgerHeader>
+    getNewestLedgerInfo() = 0;
+
+    /**
+     * @brief getLedgerInfoByHash Returns the info of the ledger with given
+     *        hash.
+     * @param ledgerHash Hash of the ledger.
+     * @return Ledger if found, otherwise no value.
+     */
+    virtual std::optional<LedgerHeader>
+    getLedgerInfoByHash(uint256 const& ledgerHash) = 0;
+
+    /**
+     * @brief getHashByIndex Returns the hash of the ledger with the given
+     *        sequence.
+     * @param ledgerIndex Ledger sequence.
+     * @return Hash of the ledger.
+     */
+    virtual uint256
+    getHashByIndex(LedgerIndex ledgerIndex) = 0;
+
+    /**
+     * @brief getHashesByIndex Returns the hashes of the ledger and its parent
+     *        as specified by the ledgerIndex.
+     * @param ledgerIndex Ledger sequence.
+     * @return Struct LedgerHashPair which contains hashes of the ledger and
+     *         its parent.
+     */
+    virtual std::optional<LedgerHashPair>
+    getHashesByIndex(LedgerIndex ledgerIndex) = 0;
+
+    /**
+     * @brief getHashesByIndex Returns hashes of each ledger and its parent for
+     *        all ledgers within the provided range.
+     * @param minSeq Minimum ledger sequence.
+     * @param maxSeq Maximum ledger sequence.
+     * @return Container that maps the sequence number of a found ledger to the
+     *         struct LedgerHashPair which contains the hashes of the ledger and
+     *         its parent.
+     */
+    virtual std::map<LedgerIndex, LedgerHashPair>
+    getHashesByIndex(LedgerIndex minSeq, LedgerIndex maxSeq) = 0;
+
+    /**
+     * @brief getTxHistory Returns the 20 most recent transactions starting from
+     *        the given number.
+     * @param startIndex First number of returned entry.
+     * @return Vector of shared pointers to transactions sorted in
+     *         descending order by ledger sequence.
+     */
+    virtual std::vector<std::shared_ptr<Transaction>>
+    getTxHistory(LedgerIndex startIndex) = 0;
+
+    /**
+     * @brief getTransactionsMinLedgerSeq Returns the minimum ledger sequence
+     *        stored in the Transactions table.
+     * @return Ledger sequence or no value if no ledgers exist.
+     */
+    virtual std::optional<LedgerIndex>
+    getTransactionsMinLedgerSeq() = 0;
+
+    /**
+     * @brief getAccountTransactionsMinLedgerSeq Returns the minimum ledger
+     *        sequence stored in the AccountTransactions table.
+     * @return Ledger sequence or no value if no ledgers exist.
+     */
+    virtual std::optional<LedgerIndex>
+    getAccountTransactionsMinLedgerSeq() = 0;
+
+    /**
+     * @brief deleteTransactionByLedgerSeq Deletes transactions from the ledger
+     *        with the given sequence.
+     * @param ledgerSeq Ledger sequence.
+     */
+    virtual void
+    deleteTransactionByLedgerSeq(LedgerIndex ledgerSeq) = 0;
+
+    /**
+     * @brief deleteBeforeLedgerSeq Deletes all ledgers with a sequence number
+     *        less than or equal to the given ledger sequence.
+     * @param ledgerSeq Ledger sequence.
+     */
+    virtual void
+    deleteBeforeLedgerSeq(LedgerIndex ledgerSeq) = 0;
+
+    /**
+     * @brief deleteTransactionsBeforeLedgerSeq Deletes all transactions with
+     *        a sequence number less than or equal to the given ledger
+     *        sequence.
+     * @param ledgerSeq Ledger sequence.
+     */
+    virtual void
+    deleteTransactionsBeforeLedgerSeq(LedgerIndex ledgerSeq) = 0;
+
+    /**
+     * @brief deleteAccountTransactionsBeforeLedgerSeq Deletes all account
+     *        transactions with a sequence number less than or equal to the
+     *        given ledger sequence.
+     * @param ledgerSeq Ledger sequence.
+     */
+    virtual void
+    deleteAccountTransactionsBeforeLedgerSeq(LedgerIndex ledgerSeq) = 0;
+
+    /**
+     * @brief getTransactionCount Returns the number of transactions.
+     * @return Number of transactions.
+     */
+    virtual std::size_t
+    getTransactionCount() = 0;
+
+    /**
+     * @brief getAccountTransactionCount Returns the number of account
+     *        transactions.
+     * @return Number of account transactions.
+     */
+    virtual std::size_t
+    getAccountTransactionCount() = 0;
+
+    /**
+     * @brief getLedgerCountMinMax Returns the minimum ledger sequence,
+     *        maximum ledger sequence and total number of saved ledgers.
+     * @return Struct CountMinMax which contains the minimum sequence,
+     *         maximum sequence and number of ledgers.
+     */
+    virtual struct CountMinMax
+    getLedgerCountMinMax() = 0;
+
+    /**
+     * @brief saveValidatedLedger Saves a ledger into the database.
+     * @param ledger The ledger.
+     * @param current True if the ledger is current.
+     * @return True if saving was successful.
+     */
+    virtual bool
+    saveValidatedLedger(std::shared_ptr<Ledger const> const& ledger, bool current) = 0;
+
+    /**
+     * @brief getLimitedOldestLedgerInfo Returns the info of the oldest ledger
+     *        whose sequence number is greater than or equal to the given
+     *        sequence number.
+     * @param ledgerFirstIndex Minimum ledger sequence.
+     * @return Ledger info if found, otherwise no value.
+     */
+    virtual std::optional<LedgerHeader>
+    getLimitedOldestLedgerInfo(LedgerIndex ledgerFirstIndex) = 0;
+
+    /**
+     * @brief getLimitedNewestLedgerInfo Returns the info of the newest ledger
+     *        whose sequence number is greater than or equal to the given
+     *        sequence number.
+     * @param ledgerFirstIndex Minimum ledger sequence.
+     * @return Ledger info if found, otherwise no value.
+     */
+    virtual std::optional<LedgerHeader>
+    getLimitedNewestLedgerInfo(LedgerIndex ledgerFirstIndex) = 0;
+
+    /**
+     * @brief getOldestAccountTxs Returns the oldest transactions for the
+     *        account that matches the given criteria starting from the provided
+     *        offset.
+     * @param options Struct AccountTxOptions which contains the criteria to
+     *        match: the account, ledger search range, the offset of the first
+     *        entry to return, the number of transactions to return, a flag if
+     *        this number is unlimited.
+     * @return Vector of pairs of found transactions and their metadata
+     *         sorted in ascending order by account sequence.
+     */
+    virtual AccountTxs
+    getOldestAccountTxs(AccountTxOptions const& options) = 0;
+
+    /**
+     * @brief getNewestAccountTxs Returns the newest transactions for the
+     *        account that matches the given criteria starting from the provided
+     *        offset.
+     * @param options Struct AccountTxOptions which contains the criteria to
+     *        match: the account, the ledger search range, the offset of  the
+     *        first entry to return, the number of transactions to return, a
+     *        flag if this number unlimited.
+     * @return Vector of pairs of found transactions and their metadata
+     *         sorted in descending order by account sequence.
+     */
+    virtual AccountTxs
+    getNewestAccountTxs(AccountTxOptions const& options) = 0;
+
+    /**
+     * @brief getOldestAccountTxsB Returns the oldest transactions in binary
+     *        form for the account that matches the given criteria starting from
+     *        the provided offset.
+     * @param options Struct AccountTxOptions which contains the criteria to
+     *        match: the account, the ledger search range, the offset of the
+     *        first entry to return, the number of transactions to return, a
+     *        flag if this number unlimited.
+     * @return Vector of tuples of found transactions, their metadata and
+     *         account sequences sorted in ascending order by account sequence.
+     */
+    virtual MetaTxsList
+    getOldestAccountTxsB(AccountTxOptions const& options) = 0;
+
+    /**
+     * @brief getNewestAccountTxsB Returns the newest transactions in binary
+     *        form for the account that matches the given criteria starting from
+     *        the provided offset.
+     * @param options Struct AccountTxOptions which contains the criteria to
+     *        match: the account, the ledger search range, the offset of the
+     *        first entry to return, the number of transactions to return, a
+     *        flag if this number is unlimited.
+     * @return Vector of tuples of found transactions, their metadata and
+     *         account sequences sorted in descending order by account
+     *         sequence.
+     */
+    virtual MetaTxsList
+    getNewestAccountTxsB(AccountTxOptions const& options) = 0;
+
+    /**
+     * @brief oldestAccountTxPage Returns the oldest transactions for the
+     *        account that matches the given criteria starting from the
+     *        provided marker.
+     * @param options Struct AccountTxPageOptions which contains the criteria to
+     *        match: the account, the ledger search range, the marker of first
+     *        returned entry, the number of transactions to return, a flag if
+     *        this number is unlimited.
+     * @return Vector of pairs of found transactions and their metadata
+     *         sorted in ascending order by account sequence and a marker
+     *         for the next search if the search was not finished.
+     */
+    virtual std::pair<AccountTxs, std::optional<AccountTxMarker>>
+    oldestAccountTxPage(AccountTxPageOptions const& options) = 0;
+
+    /**
+     * @brief newestAccountTxPage Returns the newest transactions for the
+     *        account that matches the given criteria starting from the provided
+     *        marker.
+     * @param options Struct AccountTxPageOptions which contains the criteria to
+     *        match: the account, the ledger search range, the marker of the
+     *        first returned entry, the number of transactions to return, a flag
+     *        if this number unlimited.
+     * @return Vector of pairs of found transactions and their metadata
+     *         sorted in descending order by account sequence and a marker
+     *         for the next search if the search was not finished.
+     */
+    virtual std::pair<AccountTxs, std::optional<AccountTxMarker>>
+    newestAccountTxPage(AccountTxPageOptions const& options) = 0;
+
+    /**
+     * @brief oldestAccountTxPageB Returns the oldest transactions in binary
+     *        form for the account that matches the given criteria starting from
+     *        the provided marker.
+     * @param options Struct AccountTxPageOptions which contains criteria to
+     *        match: the account, the ledger search range, the marker of the
+     *        first returned entry, the number of transactions to return, a flag
+     *        if this number unlimited.
+     * @return Vector of tuples of found transactions, their metadata and
+     *         account sequences sorted in ascending order by account
+     *         sequence and a marker for the next search if the search was not
+     *         finished.
+     */
+    virtual std::pair<MetaTxsList, std::optional<AccountTxMarker>>
+    oldestAccountTxPageB(AccountTxPageOptions const& options) = 0;
+
+    /**
+     * @brief newestAccountTxPageB Returns the newest transactions in binary
+     *        form for the account that matches the given criteria starting from
+     *        the provided marker.
+     * @param options Struct AccountTxPageOptions which contains the criteria to
+     *        match: the account, the ledger search range, the marker of the
+     *        first returned entry, the number of transactions to return, a flag
+     *        if this number is unlimited.
+     * @return Vector of tuples of found transactions, their metadata and
+     *         account sequences sorted in descending order by account
+     *         sequence and a marker for the next search if the search was not
+     *         finished.
+     */
+    virtual std::pair<MetaTxsList, std::optional<AccountTxMarker>>
+    newestAccountTxPageB(AccountTxPageOptions const& options) = 0;
+
+    /**
+     * @brief getTransaction Returns the transaction with the given hash. If a
+     *        range is provided but the transaction is not found, then check if
+     *        all ledgers in the range are present in the database.
+     * @param id Hash of the transaction.
+     * @param range Range of ledgers to check, if present.
+     * @param ec Default error code value.
+     * @return Transaction and its metadata if found, otherwise TxSearched::all
+     *         if a range is provided and all ledgers from the range are present
+     *         in the database, TxSearched::some if a range is provided and not
+     *         all ledgers are present, TxSearched::unknown if the range is not
+     *         provided or a deserializing error occurred. In the last case the
+     *         error code is returned via the ec parameter, in other cases the
+     *         default error code is not changed.
+     */
+    virtual std::variant<AccountTx, TxSearched>
+    getTransaction(uint256 const& id, std::optional<ClosedInterval<uint32_t>> const& range, error_code_i& ec) = 0;
+
+    /**
+     * @brief getKBUsedAll Returns the amount of space used by all databases.
+     * @return Space in kilobytes.
+     */
+    virtual uint32_t
+    getKBUsedAll() = 0;
+
+    /**
+     * @brief getKBUsedLedger Returns the amount of space space used by the
+     *        ledger database.
+     * @return Space in kilobytes.
+     */
+    virtual uint32_t
+    getKBUsedLedger() = 0;
+
+    /**
+     * @brief getKBUsedTransaction Returns the amount of space used by the
+     *        transaction database.
+     * @return Space in kilobytes.
+     */
+    virtual uint32_t
+    getKBUsedTransaction() = 0;
+
+    /**
+     * @brief Closes the ledger database
+     */
+    virtual void
+    closeLedgerDB() = 0;
+
+    /**
+     * @brief Closes the transaction database
+     */
+    virtual void
+    closeTransactionDB() = 0;
+};
+
+template <class T, class C>
+T
+rangeCheckedCast(C c)
+{
+    if ((c > std::numeric_limits<T>::max()) || (!std::numeric_limits<T>::is_signed && c < 0) ||
+        (std::numeric_limits<T>::is_signed && std::numeric_limits<C>::is_signed &&
+         c < std::numeric_limits<T>::lowest()))
+    {
+        // This should never happen
+        // LCOV_EXCL_START
+        UNREACHABLE("xrpl::rangeCheckedCast : domain error");
+        JLOG(debugLog().error()) << "rangeCheckedCast domain error:"
+                                 << " value = " << c << " min = " << std::numeric_limits<T>::lowest()
+                                 << " max: " << std::numeric_limits<T>::max();
+        // LCOV_EXCL_STOP
+    }
+
+    return static_cast<T>(c);
+}
+
+}  // namespace xrpl

include/xrpl/server/InfoSub.h

@@ -1,12 +1,11 @@
 #pragma once
 
-#include <xrpld/app/misc/Manifest.h>
-
 #include <xrpl/basics/CountedObject.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/Book.h>
 #include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/resource/Consumer.h>
+#include <xrpl/server/Manifest.h>
 
 namespace xrpl {
 
@@ -132,6 +131,7 @@ public:
 
         virtual bool
         subPeerStatus(ref ispListener) = 0;
+
         virtual bool
         unsubPeerStatus(std::uint64_t uListener) = 0;
         virtual void

include/xrpl/server/NetworkOPs.h

@@ -1,13 +1,12 @@
 #pragma once
 
-#include <xrpld/app/consensus/RCLCxPeerPos.h>
-#include <xrpld/app/ledger/Ledger.h>
-#include <xrpld/rpc/InfoSub.h>
-
 #include <xrpl/core/JobQueue.h>
-#include <xrpl/ledger/ReadView.h>
+#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/protocol/STValidation.h>
+#include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/messages.h>
+#include <xrpl/server/InfoSub.h>
+#include <xrpl/shamap/SHAMap.h>
 
 #include <boost/asio.hpp>
 
@@ -19,10 +18,13 @@ namespace xrpl {
 // Master operational handler, server sequencer, network tracker
 
 class Peer;
+class STTx;
+class ReadView;
 class LedgerMaster;
 class Transaction;
 class ValidatorKeys;
 class CanonicalTXSet;
+class RCLCxPeerPos;
 
 // This is the primary interface into the "client" portion of the program.
 // Code that wants to do normal operations on the network such as
@@ -245,20 +247,4 @@ public:
     stateAccounting(Json::Value& obj) = 0;
 };
 
-//------------------------------------------------------------------------------
-
-std::unique_ptr<NetworkOPs>
-make_NetworkOPs(
-    Application& app,
-    NetworkOPs::clock_type& clock,
-    bool standalone,
-    std::size_t minPeerCount,
-    bool start_valid,
-    JobQueue& job_queue,
-    LedgerMaster& ledgerMaster,
-    ValidatorKeys const& validatorKeys,
-    boost::asio::io_context& io_svc,
-    beast::Journal journal,
-    beast::insight::Collector::ptr const& collector);
-
 }  // namespace xrpl

include/xrpl/server/State.h

@@ -1,10 +1,8 @@
 #pragma once
 
-#include <xrpld/app/ledger/Ledger.h>
+#include <xrpl/protocol/Protocol.h>
-#include <xrpld/app/misc/Manifest.h>
+#include <xrpl/rdb/DatabaseCon.h>
-#include <xrpld/core/Config.h>
+#include <xrpl/server/Manifest.h>
-#include <xrpld/core/DatabaseCon.h>
-#include <xrpld/peerfinder/detail/Store.h>
 
 #include <boost/filesystem.hpp>
 

include/xrpl/server/Vacuum.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/core/DatabaseCon.h>
+#include <xrpl/rdb/DatabaseCon.h>
 
 namespace xrpl {
 

include/xrpl/server/Wallet.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <xrpld/app/misc/Manifest.h>
+#include <xrpl/core/PeerReservationTable.h>
-#include <xrpld/core/Config.h>
+#include <xrpl/rdb/DatabaseCon.h>
-#include <xrpld/core/DatabaseCon.h>
+#include <xrpl/server/Manifest.h>
-#include <xrpld/overlay/PeerReservationTable.h>
 
 namespace xrpl {
 

include/xrpl/server/detail/BaseHTTPPeer.h

@@ -218,7 +218,7 @@ void
 BaseHTTPPeer<Handler, Impl>::close()
 {
     if (!strand_.running_in_this_thread())
-        return post(strand_, std::bind((void(BaseHTTPPeer::*)(void)) & BaseHTTPPeer::close, impl().shared_from_this()));
+        return post(strand_, std::bind((void (BaseHTTPPeer::*)(void))&BaseHTTPPeer::close, impl().shared_from_this()));
     boost::beast::get_lowest_layer(impl().stream_).close();
 }
 
@@ -436,7 +436,7 @@ BaseHTTPPeer<Handler, Impl>::close(bool graceful)
         return post(
             strand_,
             std::bind(
-                (void(BaseHTTPPeer::*)(bool)) & BaseHTTPPeer<Handler, Impl>::close,
+                (void (BaseHTTPPeer::*)(bool))&BaseHTTPPeer<Handler, Impl>::close,
                 impl().shared_from_this(),
                 graceful));
 

include/xrpl/server/detail/BaseWSPeer.h

@@ -178,8 +178,9 @@ BaseWSPeer<Handler, Impl>::run()
     impl().ws_.control_callback(control_callback_);
     start_timer();
     close_on_timer_ = true;
-    impl().ws_.set_option(boost::beast::websocket::stream_base::decorator(
+    impl().ws_.set_option(boost::beast::websocket::stream_base::decorator([](auto& res) {
-        [](auto& res) { res.set(boost::beast::http::field::server, BuildInfo::getFullVersionString()); }));
+        res.set(boost::beast::http::field::server, BuildInfo::getFullVersionString());
+    }));
     impl().ws_.async_accept(
         request_,
         bind_executor(

include/xrpl/tx/ApplyContext.h

@@ -1,9 +1,7 @@
 #pragma once
 
-#include <xrpld/app/main/Application.h>
-#include <xrpld/core/Config.h>
-
 #include <xrpl/beast/utility/Journal.h>
+#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/ledger/ApplyViewImpl.h>
 #include <xrpl/protocol/STTx.h>
 #include <xrpl/protocol/XRPAmount.h>
@@ -17,7 +15,7 @@ class ApplyContext
 {
 public:
     explicit ApplyContext(
-        Application& app,
+        ServiceRegistry& registry,
         OpenView& base,
         std::optional<uint256 const> const& parentBatchId,
         STTx const& tx,
@@ -27,19 +25,19 @@ public:
         beast::Journal journal = beast::Journal{beast::Journal::getNullSink()});
 
     explicit ApplyContext(
-        Application& app,
+        ServiceRegistry& registry,
         OpenView& base,
         STTx const& tx,
         TER preclaimResult,
         XRPAmount baseFee,
         ApplyFlags flags,
         beast::Journal journal = beast::Journal{beast::Journal::getNullSink()})
-        : ApplyContext(app, base, std::nullopt, tx, preclaimResult, baseFee, flags, journal)
+        : ApplyContext(registry, base, std::nullopt, tx, preclaimResult, baseFee, flags, journal)
     {
         XRPL_ASSERT((flags & tapBATCH) == 0, "Batch apply flag should not be set");
     }
 
-    Application& app;
+    ServiceRegistry& registry;
     STTx const& tx;
     TER const preclaimResult;
     XRPAmount const baseFee;
@@ -90,11 +88,12 @@ public:
 
     /** Visit unapplied changes. */
     void
-    visit(std::function<void(
+    visit(
-              uint256 const& key,
+        std::function<void(
-              bool isDelete,
+            uint256 const& key,
-              std::shared_ptr<SLE const> const& before,
+            bool isDelete,
-              std::shared_ptr<SLE const> const& after)> const& func);
+            std::shared_ptr<SLE const> const& before,
+            std::shared_ptr<SLE const> const& after)> const& func);
 
     void
     destroyXRP(XRPAmount const& fee)

include/xrpl/tx/SignerEntries.h

@@ -1,11 +1,10 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>  // NotTEC
-
 #include <xrpl/basics/Expected.h>        //
 #include <xrpl/beast/utility/Journal.h>  // beast::Journal
 #include <xrpl/protocol/TER.h>           // temMALFORMED
 #include <xrpl/protocol/UintTypes.h>     // AccountID
+#include <xrpl/tx/Transactor.h>          // NotTEC
 
 #include <optional>
 #include <string_view>

include/xrpl/tx/Transactor.h

@@ -1,12 +1,11 @@
 #pragma once
 
-#include <xrpld/app/tx/applySteps.h>
-#include <xrpld/app/tx/detail/ApplyContext.h>
-
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/beast/utility/WrappedSink.h>
 #include <xrpl/protocol/Permissions.h>
 #include <xrpl/protocol/XRPAmount.h>
+#include <xrpl/tx/ApplyContext.h>
+#include <xrpl/tx/applySteps.h>
 
 namespace xrpl {
 
@@ -14,7 +13,7 @@ namespace xrpl {
 struct PreflightContext
 {
 public:
-    Application& app;
+    ServiceRegistry& registry;
     STTx const& tx;
     Rules const rules;
     ApplyFlags flags;
@@ -22,24 +21,24 @@ public:
     beast::Journal const j;
 
     PreflightContext(
-        Application& app_,
+        ServiceRegistry& registry_,
         STTx const& tx_,
         uint256 parentBatchId_,
         Rules const& rules_,
         ApplyFlags flags_,
         beast::Journal j_ = beast::Journal{beast::Journal::getNullSink()})
-        : app(app_), tx(tx_), rules(rules_), flags(flags_), parentBatchId(parentBatchId_), j(j_)
+        : registry(registry_), tx(tx_), rules(rules_), flags(flags_), parentBatchId(parentBatchId_), j(j_)
     {
         XRPL_ASSERT((flags_ & tapBATCH) == tapBATCH, "Batch apply flag should be set");
     }
 
     PreflightContext(
-        Application& app_,
+        ServiceRegistry& registry_,
         STTx const& tx_,
         Rules const& rules_,
         ApplyFlags flags_,
         beast::Journal j_ = beast::Journal{beast::Journal::getNullSink()})
-        : app(app_), tx(tx_), rules(rules_), flags(flags_), j(j_)
+        : registry(registry_), tx(tx_), rules(rules_), flags(flags_), j(j_)
     {
         XRPL_ASSERT((flags_ & tapBATCH) == 0, "Batch apply flag should not be set");
     }
@@ -52,7 +51,7 @@ public:
 struct PreclaimContext
 {
 public:
-    Application& app;
+    ServiceRegistry& registry;
     ReadView const& view;
     TER preflightResult;
     ApplyFlags flags;
@@ -61,14 +60,14 @@ public:
     beast::Journal const j;
 
     PreclaimContext(
-        Application& app_,
+        ServiceRegistry& registry_,
         ReadView const& view_,
         TER preflightResult_,
         STTx const& tx_,
         ApplyFlags flags_,
         std::optional<uint256> parentBatchId_,
         beast::Journal j_ = beast::Journal{beast::Journal::getNullSink()})
-        : app(app_)
+        : registry(registry_)
         , view(view_)
         , preflightResult(preflightResult_)
         , flags(flags_)
@@ -82,13 +81,13 @@ public:
     }
 
     PreclaimContext(
-        Application& app_,
+        ServiceRegistry& registry_,
         ReadView const& view_,
         TER preflightResult_,
         STTx const& tx_,
         ApplyFlags flags_,
         beast::Journal j_ = beast::Journal{beast::Journal::getNullSink()})
-        : PreclaimContext(app_, view_, preflightResult_, tx_, flags_, std::nullopt, j_)
+        : PreclaimContext(registry_, view_, preflightResult_, tx_, flags_, std::nullopt, j_)
     {
         XRPL_ASSERT((flags_ & tapBATCH) == 0, "Batch apply flag should not be set");
     }
@@ -225,14 +224,14 @@ protected:
     /** Compute the minimum fee required to process a transaction
         with a given baseFee based on the current server load.
 
-        @param app The application hosting the server
+        @param registry The service registry.
         @param baseFee The base fee of a candidate transaction
             @see xrpl::calculateBaseFee
         @param fees Fee settings from the current ledger
         @param flags Transaction processing fees
      */
     static XRPAmount
-    minimumFee(Application& app, XRPAmount baseFee, Fees const& fees, ApplyFlags flags);
+    minimumFee(ServiceRegistry& registry, XRPAmount baseFee, Fees const& fees, ApplyFlags flags);
 
     // Returns the fee in fee units, not scaled for load.
     static XRPAmount

include/xrpl/tx/apply.h

@@ -1,18 +1,16 @@
 #pragma once
 
-#include <xrpld/app/tx/applySteps.h>
-#include <xrpld/core/Config.h>
-
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/View.h>
 #include <xrpl/protocol/STTx.h>
+#include <xrpl/tx/applySteps.h>
 
 #include <utility>
 
 namespace xrpl {
 
-class Application;
 class HashRouter;
+class ServiceRegistry;
 
 /** Describes the pre-processing validity of a transaction.
 
@@ -41,7 +39,7 @@ enum class Validity {
     @see Validity
 */
 std::pair<Validity, std::string>
-checkValidity(HashRouter& router, STTx const& tx, Rules const& rules, Config const& config);
+checkValidity(HashRouter& router, STTx const& tx, Rules const& rules);
 
 /** Sets the validity of a given transaction in the cache.
 
@@ -97,7 +95,7 @@ forceValidity(HashRouter& router, uint256 const& txid, Validity validity);
             whether or not the transaction was applied.
 */
 ApplyResult
-apply(Application& app, OpenView& view, STTx const& tx, ApplyFlags flags, beast::Journal journal);
+apply(ServiceRegistry& registry, OpenView& view, STTx const& tx, ApplyFlags flags, beast::Journal journal);
 
 /** Enum class for return value from `applyTransaction`
 
@@ -121,7 +119,7 @@ enum class ApplyTransactionResult {
 */
 ApplyTransactionResult
 applyTransaction(
-    Application& app,
+    ServiceRegistry& registry,
     OpenView& view,
     STTx const& tx,
     bool retryAssured,

include/xrpl/tx/applySteps.h

@@ -5,7 +5,7 @@
 
 namespace xrpl {
 
-class Application;
+class ServiceRegistry;
 class STTx;
 class TxQ;
 
@@ -240,11 +240,11 @@ public:
 */
 /** @{ */
 PreflightResult
-preflight(Application& app, Rules const& rules, STTx const& tx, ApplyFlags flags, beast::Journal j);
+preflight(ServiceRegistry& registry, Rules const& rules, STTx const& tx, ApplyFlags flags, beast::Journal j);
 
 PreflightResult
 preflight(
-    Application& app,
+    ServiceRegistry& registry,
     Rules const& rules,
     uint256 const& parentBatchId,
     STTx const& tx,
@@ -281,7 +281,7 @@ preflight(
     this transaction.
 */
 PreclaimResult
-preclaim(PreflightResult const& preflightResult, Application& app, OpenView const& view);
+preclaim(PreflightResult const& preflightResult, ServiceRegistry& registry, OpenView const& view);
 
 /** Compute only the expected base fee for a transaction.
 
@@ -323,7 +323,7 @@ calculateDefaultBaseFee(ReadView const& view, STTx const& tx);
 
     @param preclaimResult The result of a previous
     call to `preclaim` for the transaction.
-    @param app The current running `Application`.
+    @param registry The service registry.
     @param view The open ledger that the transaction
     will attempt to be applied to.
 
@@ -333,6 +333,6 @@ calculateDefaultBaseFee(ReadView const& view, STTx const& tx);
     whether or not the transaction was applied.
 */
 ApplyResult
-doApply(PreclaimResult const& preclaimResult, Application& app, OpenView& view);
+doApply(PreclaimResult const& preclaimResult, ServiceRegistry& registry, OpenView& view);
 
 }  // namespace xrpl

include/xrpl/tx/paths/Flow.h

@@ -1,9 +1,8 @@
 #pragma once
 
-#include <xrpld/app/paths/RippleCalc.h>
-#include <xrpld/app/paths/detail/Steps.h>
-
 #include <xrpl/protocol/Quality.h>
+#include <xrpl/tx/paths/RippleCalc.h>
+#include <xrpl/tx/paths/detail/Steps.h>
 
 namespace xrpl {
 

include/xrpl/tx/paths/OfferStream.h

@@ -1,12 +1,11 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/BookTip.h>
-#include <xrpld/app/tx/detail/Offer.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/chrono.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/tx/paths/BookTip.h>
+#include <xrpl/tx/paths/Offer.h>
 
 #include <boost/container/flat_set.hpp>
 

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

@@ -1,10 +1,9 @@
 #pragma once
 
-#include <xrpld/app/paths/detail/AmountSpec.h>
-
 #include <xrpl/ledger/PaymentSandbox.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/XRPAmount.h>
+#include <xrpl/tx/paths/detail/AmountSpec.h>
 
 #include <boost/container/flat_map.hpp>
 

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

@@ -1,13 +1,12 @@
 #pragma once
 
-#include <xrpld/app/paths/detail/AmountSpec.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/protocol/Quality.h>
 #include <xrpl/protocol/QualityFunction.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 #include <xrpl/protocol/TER.h>
+#include <xrpl/tx/paths/detail/AmountSpec.h>
 
 #include <boost/container/flat_set.hpp>
 

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

@@ -1,18 +1,17 @@
 #pragma once
 
-#include <xrpld/app/misc/AMMHelpers.h>
-#include <xrpld/app/paths/AMMContext.h>
-#include <xrpld/app/paths/Flow.h>
-#include <xrpld/app/paths/detail/AmountSpec.h>
-#include <xrpld/app/paths/detail/FlatSets.h>
-#include <xrpld/app/paths/detail/FlowDebugInfo.h>
-#include <xrpld/app/paths/detail/Steps.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/Credit.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/XRPAmount.h>
+#include <xrpl/tx/paths/Flow.h>
+#include <xrpl/tx/paths/detail/AmountSpec.h>
+#include <xrpl/tx/paths/detail/FlatSets.h>
+#include <xrpl/tx/paths/detail/FlowDebugInfo.h>
+#include <xrpl/tx/paths/detail/Steps.h>
+#include <xrpl/tx/transactors/AMM/AMMContext.h>
+#include <xrpl/tx/transactors/AMM/AMMHelpers.h>
 
 #include <boost/container/flat_set.hpp>
 

include/xrpl/tx/transactors/AMM/AMMBid.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/AMM/AMMClawback.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 class Sandbox;

include/xrpl/tx/transactors/AMM/AMMCreate.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/AMM/AMMDelete.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/AMM/AMMDeposit.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/AMM/AMMVote.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

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

@@ -1,8 +1,7 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
-
 #include <xrpl/ledger/View.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Batch.h

@@ -1,10 +1,8 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
-#include <xrpld/core/Config.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Change.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Check/CancelCheck.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Check/CashCheck.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Check/CreateCheck.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Clawback.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/CreateTicket.h

@@ -1,7 +1,6 @@
 #pragma once
 
-#include <xrpld/app/ledger/Ledger.h>
+#include <xrpl/tx/Transactor.h>
-#include <xrpld/app/tx/detail/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Credentials.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/DID.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Delegate/DelegateSet.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/DeleteAccount.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/DeleteOracle.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/DepositPreauth.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Escrow.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/LedgerStateFix.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Lending/LoanBrokerCoverClawback.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Lending/LoanBrokerCoverDeposit.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Lending/LoanBrokerCoverWithdraw.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {
 

include/xrpl/tx/transactors/Lending/LoanBrokerDelete.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <xrpld/app/tx/detail/Transactor.h>
+#include <xrpl/tx/Transactor.h>
 
 namespace xrpl {