diff --git a/.github/scripts/levelization/results/ordering.txt b/.github/scripts/levelization/results/ordering.txt
index 1de6f803f3..5f8812c49b 100644
--- a/.github/scripts/levelization/results/ordering.txt
+++ b/.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
@@ -56,7 +58,7 @@ 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
@@ -158,6 +160,8 @@ 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
@@ -165,6 +169,7 @@ xrpl.core > xrpl.protocol
 xrpl.json > xrpl.basics
 xrpl.ledger > xrpl.basics
 xrpl.ledger > xrpl.protocol
+xrpl.ledger > xrpl.server
 xrpl.net > xrpl.basics
 xrpl.nodestore > xrpl.basics
 xrpl.nodestore > xrpl.protocol
@@ -179,7 +184,6 @@ xrpl.resource > xrpl.protocol
 xrpl.server > xrpl.basics
 xrpl.server > xrpl.core
 xrpl.server > xrpl.json
-xrpl.server > xrpl.ledger
 xrpl.server > xrpl.protocol
 xrpl.server > xrpl.rdb
 xrpl.server > xrpl.resource
@@ -189,8 +193,8 @@ xrpl.shamap > xrpl.nodestore
 xrpl.shamap > xrpl.protocol
 xrpld.app > test.unit_test
 xrpld.app > xrpl.basics
+xrpld.app > xrpl.conditions
 xrpld.app > xrpl.core
-xrpld.app > xrpld.conditions
 xrpld.app > xrpld.consensus
 xrpld.app > xrpld.core
 xrpld.app > xrpl.json
@@ -202,8 +206,6 @@ xrpld.app > xrpl.rdb
 xrpld.app > xrpl.resource
 xrpld.app > xrpl.server
 xrpld.app > xrpl.shamap
-xrpld.conditions > xrpl.basics
-xrpld.conditions > xrpl.protocol
 xrpld.consensus > xrpl.basics
 xrpld.consensus > xrpl.json
 xrpld.consensus > xrpl.protocol
diff --git a/cmake/XrplCore.cmake b/cmake/XrplCore.cmake
index ba14899bd9..3380ca85cd 100644
--- a/cmake/XrplCore.cmake
+++ b/cmake/XrplCore.cmake
@@ -98,9 +98,18 @@ 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
-                                                 xrpl.libxrpl.rdb)
+target_link_libraries(
+    xrpl.libxrpl.ledger
+    PUBLIC xrpl.libxrpl.basics
+           xrpl.libxrpl.json
+           xrpl.libxrpl.protocol
+           xrpl.libxrpl.rdb
+           xrpl.libxrpl.server
+           xrpl.libxrpl.conditions)
 
 add_library(xrpl.libxrpl)
 set_target_properties(xrpl.libxrpl PROPERTIES OUTPUT_NAME xrpl)
@@ -115,6 +124,7 @@ target_link_modules(
     PUBLIC
     basics
     beast
+    conditions
     core
     crypto
     json
diff --git a/cmake/XrplInstall.cmake b/cmake/XrplInstall.cmake
index 340dca553b..d2fef5d488 100644
--- a/cmake/XrplInstall.cmake
+++ b/cmake/XrplInstall.cmake
@@ -20,6 +20,7 @@ install(TARGETS common
                 xrpl.libxrpl
                 xrpl.libxrpl.basics
                 xrpl.libxrpl.beast
+                xrpl.libxrpl.conditions
                 xrpl.libxrpl.core
                 xrpl.libxrpl.crypto
                 xrpl.libxrpl.json
diff --git a/src/xrpld/conditions/Condition.h b/include/xrpl/conditions/Condition.h
similarity index 98%
rename from src/xrpld/conditions/Condition.h
rename to include/xrpl/conditions/Condition.h
index 50872e75ef..6b306a3982 100644
--- a/src/xrpld/conditions/Condition.h
+++ b/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>
diff --git a/src/xrpld/conditions/Fulfillment.h b/include/xrpl/conditions/Fulfillment.h
similarity index 98%
rename from src/xrpld/conditions/Fulfillment.h
rename to include/xrpl/conditions/Fulfillment.h
index 840e9f9993..04d0b2aa1e 100644
--- a/src/xrpld/conditions/Fulfillment.h
+++ b/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 {
diff --git a/src/xrpld/conditions/detail/PreimageSha256.h b/include/xrpl/conditions/detail/PreimageSha256.h
similarity index 95%
rename from src/xrpld/conditions/detail/PreimageSha256.h
rename to include/xrpl/conditions/detail/PreimageSha256.h
index f3ce1a03e0..8726473c2d 100644
--- a/src/xrpld/conditions/detail/PreimageSha256.h
+++ b/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>
diff --git a/src/xrpld/conditions/detail/error.h b/include/xrpl/conditions/detail/error.h
similarity index 100%
rename from src/xrpld/conditions/detail/error.h
rename to include/xrpl/conditions/detail/error.h
diff --git a/src/xrpld/conditions/detail/utils.h b/include/xrpl/conditions/detail/utils.h
similarity index 98%
rename from src/xrpld/conditions/detail/utils.h
rename to include/xrpl/conditions/detail/utils.h
index 2a4187718b..17d93d43b5 100644
--- a/src/xrpld/conditions/detail/utils.h
+++ b/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>
 
diff --git a/src/xrpld/app/misc/HashRouter.h b/include/xrpl/core/HashRouter.h
similarity index 99%
rename from src/xrpld/app/misc/HashRouter.h
rename to include/xrpl/core/HashRouter.h
index ad6da520bd..dfc57081ee 100644
--- a/src/xrpld/app/misc/HashRouter.h
+++ b/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
diff --git a/include/xrpl/core/ServiceRegistry.h b/include/xrpl/core/ServiceRegistry.h
index 86591a815f..fabf61f9e4 100644
--- a/include/xrpl/core/ServiceRegistry.h
+++ b/include/xrpl/core/ServiceRegistry.h
@@ -214,6 +214,13 @@ public:
     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&
diff --git a/src/xrpld/app/ledger/AcceptedLedgerTx.h b/include/xrpl/ledger/AcceptedLedgerTx.h
similarity index 92%
rename from src/xrpld/app/ledger/AcceptedLedgerTx.h
rename to include/xrpl/ledger/AcceptedLedgerTx.h
index 6c936bbcf2..d07016b860 100644
--- a/src/xrpld/app/ledger/AcceptedLedgerTx.h
+++ b/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.
 
diff --git a/src/xrpld/app/ledger/BookListeners.h b/include/xrpl/ledger/BookListeners.h
similarity index 100%
rename from src/xrpld/app/ledger/BookListeners.h
rename to include/xrpl/ledger/BookListeners.h
diff --git a/include/xrpl/ledger/OrderBookDB.h b/include/xrpl/ledger/OrderBookDB.h
new file mode 100644
index 0000000000..3d689607bf
--- /dev/null
+++ b/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
diff --git a/include/xrpl/server/NetworkOPs.h b/include/xrpl/server/NetworkOPs.h
index cfe0021c07..ce55f667f7 100644
--- a/include/xrpl/server/NetworkOPs.h
+++ b/include/xrpl/server/NetworkOPs.h
@@ -2,7 +2,6 @@
 
 #include <xrpl/core/JobQueue.h>
 #include <xrpl/core/ServiceRegistry.h>
-#include <xrpl/ledger/ReadView.h>
 #include <xrpl/protocol/STValidation.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/messages.h>
@@ -19,6 +18,8 @@ namespace xrpl {
 // Master operational handler, server sequencer, network tracker
 
 class Peer;
+class STTx;
+class ReadView;
 class LedgerMaster;
 class Transaction;
 class ValidatorKeys;
diff --git a/src/xrpld/conditions/detail/Condition.cpp b/src/libxrpl/conditions/Condition.cpp
similarity index 97%
rename from src/xrpld/conditions/detail/Condition.cpp
rename to src/libxrpl/conditions/Condition.cpp
index 9cac75121d..30beba3402 100644
--- a/src/xrpld/conditions/detail/Condition.cpp
+++ b/src/libxrpl/conditions/Condition.cpp
@@ -1,6 +1,6 @@
-#include <xrpld/conditions/Condition.h>
-#include <xrpld/conditions/detail/PreimageSha256.h>
-#include <xrpld/conditions/detail/utils.h>
+#include <xrpl/conditions/Condition.h>
+#include <xrpl/conditions/detail/PreimageSha256.h>
+#include <xrpl/conditions/detail/utils.h>
 
 namespace xrpl {
 namespace cryptoconditions {
diff --git a/src/xrpld/conditions/detail/Fulfillment.cpp b/src/libxrpl/conditions/Fulfillment.cpp
similarity index 94%
rename from src/xrpld/conditions/detail/Fulfillment.cpp
rename to src/libxrpl/conditions/Fulfillment.cpp
index 9ecaa44ab8..11581a8705 100644
--- a/src/xrpld/conditions/detail/Fulfillment.cpp
+++ b/src/libxrpl/conditions/Fulfillment.cpp
@@ -1,9 +1,8 @@
-#include <xrpld/conditions/Condition.h>
-#include <xrpld/conditions/Fulfillment.h>
-#include <xrpld/conditions/detail/PreimageSha256.h>
-#include <xrpld/conditions/detail/utils.h>
-
 #include <xrpl/basics/safe_cast.h>
+#include <xrpl/conditions/Condition.h>
+#include <xrpl/conditions/Fulfillment.h>
+#include <xrpl/conditions/detail/PreimageSha256.h>
+#include <xrpl/conditions/detail/utils.h>
 
 namespace xrpl {
 namespace cryptoconditions {
diff --git a/src/xrpld/conditions/detail/error.cpp b/src/libxrpl/conditions/error.cpp
similarity index 98%
rename from src/xrpld/conditions/detail/error.cpp
rename to src/libxrpl/conditions/error.cpp
index 04c8d03fbb..3124be6fdd 100644
--- a/src/xrpld/conditions/detail/error.cpp
+++ b/src/libxrpl/conditions/error.cpp
@@ -1,6 +1,5 @@
-#include <xrpld/conditions/detail/error.h>
-
 #include <xrpl/basics/safe_cast.h>
+#include <xrpl/conditions/detail/error.h>
 
 #include <string>
 
diff --git a/src/xrpld/app/misc/HashRouter.cpp b/src/libxrpl/core/HashRouter.cpp
similarity index 69%
rename from src/xrpld/app/misc/HashRouter.cpp
rename to src/libxrpl/core/HashRouter.cpp
index eca46c9872..dff1394f77 100644
--- a/src/xrpld/app/misc/HashRouter.cpp
+++ b/src/libxrpl/core/HashRouter.cpp
@@ -1,5 +1,4 @@
-#include <xrpld/app/misc/HashRouter.h>
-#include <xrpld/core/Config.h>
+#include <xrpl/core/HashRouter.h>
 
 namespace xrpl {
 
@@ -108,38 +107,4 @@ HashRouter::shouldRelay(uint256 const& key) -> std::optional<std::set<PeerShortI
     return s.releasePeerSet();
 }
 
-HashRouter::Setup
-setup_HashRouter(Config const& config)
-{
-    using namespace std::chrono;
-
-    HashRouter::Setup setup;
-    auto const& section = config.section("hashrouter");
-
-    std::int32_t tmp;
-
-    if (set(tmp, "hold_time", section))
-    {
-        if (tmp < 12)
-            Throw<std::runtime_error>(
-                "HashRouter hold time must be at least 12 seconds (the "
-                "approximate validation time for three ledgers).");
-        setup.holdTime = seconds(tmp);
-    }
-    if (set(tmp, "relay_time", section))
-    {
-        if (tmp < 8)
-            Throw<std::runtime_error>(
-                "HashRouter relay time must be at least 8 seconds (the "
-                "approximate validation time for two ledgers).");
-        setup.relayTime = seconds(tmp);
-    }
-    if (setup.relayTime > setup.holdTime)
-    {
-        Throw<std::runtime_error>("HashRouter relay time must be less than or equal to hold time");
-    }
-
-    return setup;
-}
-
 }  // namespace xrpl
diff --git a/src/xrpld/app/ledger/AcceptedLedgerTx.cpp b/src/libxrpl/ledger/AcceptedLedgerTx.cpp
similarity index 96%
rename from src/xrpld/app/ledger/AcceptedLedgerTx.cpp
rename to src/libxrpl/ledger/AcceptedLedgerTx.cpp
index 2ef05e511d..3f35f7cbc2 100644
--- a/src/xrpld/app/ledger/AcceptedLedgerTx.cpp
+++ b/src/libxrpl/ledger/AcceptedLedgerTx.cpp
@@ -1,7 +1,7 @@
-#include <xrpld/app/ledger/AcceptedLedgerTx.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/StringUtilities.h>
+#include <xrpl/ledger/AcceptedLedgerTx.h>
+#include <xrpl/ledger/View.h>
 #include <xrpl/protocol/UintTypes.h>
 #include <xrpl/protocol/jss.h>
 
diff --git a/src/xrpld/app/ledger/BookListeners.cpp b/src/libxrpl/ledger/BookListeners.cpp
similarity index 95%
rename from src/xrpld/app/ledger/BookListeners.cpp
rename to src/libxrpl/ledger/BookListeners.cpp
index 4d72c6f3b3..9ba25b783a 100644
--- a/src/xrpld/app/ledger/BookListeners.cpp
+++ b/src/libxrpl/ledger/BookListeners.cpp
@@ -1,4 +1,4 @@
-#include <xrpld/app/ledger/OrderBookDB.h>
+#include <xrpl/ledger/BookListeners.h>
 
 namespace xrpl {
 
diff --git a/src/test/app/Batch_test.cpp b/src/test/app/Batch_test.cpp
index 133f10cd28..a4e00f26db 100644
--- a/src/test/app/Batch_test.cpp
+++ b/src/test/app/Batch_test.cpp
@@ -2,11 +2,11 @@
 #include <test/jtx/TestHelpers.h>
 #include <test/jtx/utility.h>
 
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/Transaction.h>
 #include <xrpld/app/tx/apply.h>
 #include <xrpld/app/tx/detail/Batch.h>
 
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/Batch.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STParsedJSON.h>
diff --git a/src/test/app/HashRouter_test.cpp b/src/test/app/HashRouter_test.cpp
index 03bb28e35a..753922a67d 100644
--- a/src/test/app/HashRouter_test.cpp
+++ b/src/test/app/HashRouter_test.cpp
@@ -1,8 +1,9 @@
-#include <xrpld/app/misc/HashRouter.h>
+#include <xrpld/app/misc/setup_HashRouter.h>
 #include <xrpld/core/Config.h>
 
 #include <xrpl/basics/chrono.h>
 #include <xrpl/beast/unit_test.h>
+#include <xrpl/core/HashRouter.h>
 
 namespace xrpl {
 namespace test {
diff --git a/src/test/app/NetworkOPs_test.cpp b/src/test/app/NetworkOPs_test.cpp
index ffca1ed79d..a4bdae9101 100644
--- a/src/test/app/NetworkOPs_test.cpp
+++ b/src/test/app/NetworkOPs_test.cpp
@@ -2,7 +2,7 @@
 #include <test/jtx/CaptureLogs.h>
 #include <test/jtx/Env.h>
 
-#include <xrpld/app/misc/HashRouter.h>
+#include <xrpl/core/HashRouter.h>
 
 namespace xrpl {
 namespace test {
diff --git a/src/test/conditions/PreimageSha256_test.cpp b/src/test/conditions/PreimageSha256_test.cpp
index 71ba526be3..c3508758a7 100644
--- a/src/test/conditions/PreimageSha256_test.cpp
+++ b/src/test/conditions/PreimageSha256_test.cpp
@@ -1,12 +1,11 @@
-#include <xrpld/conditions/Condition.h>
-#include <xrpld/conditions/Fulfillment.h>
-#include <xrpld/conditions/detail/PreimageSha256.h>
-
 #include <xrpl/basics/Buffer.h>
 #include <xrpl/basics/Slice.h>
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/basics/strHex.h>
 #include <xrpl/beast/unit_test.h>
+#include <xrpl/conditions/Condition.h>
+#include <xrpl/conditions/Fulfillment.h>
+#include <xrpl/conditions/detail/PreimageSha256.h>
 
 #include <algorithm>
 #include <string>
diff --git a/src/xrpld/app/consensus/RCLConsensus.cpp b/src/xrpld/app/consensus/RCLConsensus.cpp
index 4ebd1a502f..ad581585b1 100644
--- a/src/xrpld/app/consensus/RCLConsensus.cpp
+++ b/src/xrpld/app/consensus/RCLConsensus.cpp
@@ -8,7 +8,6 @@
 #include <xrpld/app/ledger/LocalTxs.h>
 #include <xrpld/app/ledger/OpenLedger.h>
 #include <xrpld/app/misc/AmendmentTable.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
 #include <xrpld/app/misc/NegativeUNLVote.h>
 #include <xrpld/app/misc/TxQ.h>
@@ -21,6 +20,7 @@
 #include <xrpl/basics/random.h>
 #include <xrpl/beast/core/LexicalCast.h>
 #include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/BuildInfo.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/digest.h>
diff --git a/src/xrpld/app/ledger/AcceptedLedger.cpp b/src/xrpld/app/ledger/AcceptedLedger.cpp
index 89806c2337..7ad43b2d81 100644
--- a/src/xrpld/app/ledger/AcceptedLedger.cpp
+++ b/src/xrpld/app/ledger/AcceptedLedger.cpp
@@ -4,7 +4,7 @@
 
 namespace xrpl {
 
-AcceptedLedger::AcceptedLedger(std::shared_ptr<ReadView const> const& ledger, Application& app) : mLedger(ledger)
+AcceptedLedger::AcceptedLedger(std::shared_ptr<ReadView const> const& ledger) : mLedger(ledger)
 {
     transactions_.reserve(256);
 
diff --git a/src/xrpld/app/ledger/AcceptedLedger.h b/src/xrpld/app/ledger/AcceptedLedger.h
index c0f186c781..23cee6ce35 100644
--- a/src/xrpld/app/ledger/AcceptedLedger.h
+++ b/src/xrpld/app/ledger/AcceptedLedger.h
@@ -1,6 +1,8 @@
 #pragma once
 
-#include <xrpld/app/ledger/AcceptedLedgerTx.h>
+#include <xrpl/basics/CountedObject.h>
+#include <xrpl/core/ServiceRegistry.h>
+#include <xrpl/ledger/AcceptedLedgerTx.h>
 
 namespace xrpl {
 
@@ -23,7 +25,7 @@ namespace xrpl {
 class AcceptedLedger : public CountedObject<AcceptedLedger>
 {
 public:
-    AcceptedLedger(std::shared_ptr<ReadView const> const& ledger, Application& app);
+    AcceptedLedger(std::shared_ptr<ReadView const> const& ledger);
 
     std::shared_ptr<ReadView const> const&
     getLedger() const
diff --git a/src/xrpld/app/ledger/Ledger.cpp b/src/xrpld/app/ledger/Ledger.cpp
index 0f44601679..d75e4dd22e 100644
--- a/src/xrpld/app/ledger/Ledger.cpp
+++ b/src/xrpld/app/ledger/Ledger.cpp
@@ -3,13 +3,13 @@
 #include <xrpld/app/ledger/LedgerToJson.h>
 #include <xrpld/app/ledger/PendingSaves.h>
 #include <xrpld/app/main/Application.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/consensus/LedgerTiming.h>
 #include <xrpld/core/Config.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/contract.h>
 #include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/core/JobQueue.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/nodestore/Database.h>
diff --git a/src/xrpld/app/ledger/OrderBookDB.h b/src/xrpld/app/ledger/OrderBookDB.h
deleted file mode 100644
index da604d7e22..0000000000
--- a/src/xrpld/app/ledger/OrderBookDB.h
+++ /dev/null
@@ -1,75 +0,0 @@
-#pragma once
-
-#include <xrpld/app/ledger/AcceptedLedgerTx.h>
-#include <xrpld/app/ledger/BookListeners.h>
-#include <xrpld/app/main/Application.h>
-
-#include <xrpl/protocol/MultiApiJson.h>
-#include <xrpl/protocol/UintTypes.h>
-
-#include <mutex>
-#include <optional>
-
-namespace xrpl {
-
-class OrderBookDB
-{
-public:
-    explicit OrderBookDB(Application& app);
-
-    void
-    setup(std::shared_ptr<ReadView const> const& ledger);
-    void
-    update(std::shared_ptr<ReadView const> const& ledger);
-
-    void
-    addOrderBook(Book const&);
-
-    /** @return a list of all orderbooks that want this issuerID and currencyID.
-     */
-    std::vector<Book>
-    getBooksByTakerPays(Issue const&, std::optional<Domain> const& domain = std::nullopt);
-
-    /** @return a count of all orderbooks that want this issuerID and
-        currencyID. */
-    int
-    getBookSize(Issue const&, std::optional<Domain> const& domain = std::nullopt);
-
-    bool
-    isBookToXRP(Issue const&, std::optional<Domain> domain = std::nullopt);
-
-    BookListeners::pointer
-    getBookListeners(Book const&);
-    BookListeners::pointer
-    makeBookListeners(Book const&);
-
-    // see if this txn effects any orderbook
-    void
-    processTxn(std::shared_ptr<ReadView const> const& ledger, AcceptedLedgerTx const& alTx, MultiApiJson const& jvObj);
-
-private:
-    Application& app_;
-
-    // Maps order books by "issue in" to "issue out":
-    hardened_hash_map<Issue, hardened_hash_set<Issue>> allBooks_;
-
-    hardened_hash_map<std::pair<Issue, Domain>, hardened_hash_set<Issue>> domainBooks_;
-
-    // does an order book to XRP exist
-    hash_set<Issue> xrpBooks_;
-
-    // does an order book to XRP exist
-    hash_set<std::pair<Issue, Domain>> xrpDomainBooks_;
-
-    std::recursive_mutex mLock;
-
-    using BookToListenersMap = hash_map<Book, BookListeners::pointer>;
-
-    BookToListenersMap mListeners;
-
-    std::atomic<std::uint32_t> seq_;
-
-    beast::Journal const j_;
-};
-
-}  // namespace xrpl
diff --git a/src/xrpld/app/ledger/OrderBookDB.cpp b/src/xrpld/app/ledger/OrderBookDBImpl.cpp
similarity index 84%
rename from src/xrpld/app/ledger/OrderBookDB.cpp
rename to src/xrpld/app/ledger/OrderBookDBImpl.cpp
index 6450544f92..62c03fb7ca 100644
--- a/src/xrpld/app/ledger/OrderBookDB.cpp
+++ b/src/xrpld/app/ledger/OrderBookDBImpl.cpp
@@ -1,6 +1,5 @@
 #include <xrpld/app/ledger/LedgerMaster.h>
-#include <xrpld/app/ledger/OrderBookDB.h>
-#include <xrpld/app/main/Application.h>
+#include <xrpld/app/ledger/OrderBookDBImpl.h>
 #include <xrpld/app/misc/AMMUtils.h>
 #include <xrpld/core/Config.h>
 
@@ -11,14 +10,25 @@
 
 namespace xrpl {
 
-OrderBookDB::OrderBookDB(Application& app) : app_(app), seq_(0), j_(app.journal("OrderBookDB"))
+OrderBookDBImpl::OrderBookDBImpl(ServiceRegistry& registry, OrderBookDBConfig const& config)
+    : registry_(registry)
+    , pathSearchMax_(config.pathSearchMax)
+    , standalone_(config.standalone)
+    , seq_(0)
+    , j_(registry.journal("OrderBookDB"))
 {
 }
 
-void
-OrderBookDB::setup(std::shared_ptr<ReadView const> const& ledger)
+std::unique_ptr<OrderBookDB>
+make_OrderBookDB(ServiceRegistry& registry, OrderBookDBConfig const& config)
 {
-    if (!app_.config().standalone() && app_.getOPs().isNeedNetworkLedger())
+    return std::make_unique<OrderBookDBImpl>(registry, config);
+}
+
+void
+OrderBookDBImpl::setup(std::shared_ptr<ReadView const> const& ledger)
+{
+    if (!standalone_ && registry_.getOPs().isNeedNetworkLedger())
     {
         JLOG(j_.warn()) << "Eliding full order book update: no ledger";
         return;
@@ -40,19 +50,20 @@ OrderBookDB::setup(std::shared_ptr<ReadView const> const& ledger)
 
     JLOG(j_.debug()) << "Full order book update: " << seq << " to " << ledger->seq();
 
-    if (app_.config().PATH_SEARCH_MAX != 0)
+    if (pathSearchMax_ != 0)
     {
-        if (app_.config().standalone())
+        if (standalone_)
             update(ledger);
         else
-            app_.getJobQueue().addJob(jtUPDATE_PF, "OrderBookUpd", [this, ledger]() { update(ledger); });
+            registry_.getJobQueue().addJob(
+                jtUPDATE_PF, "OrderBookUpd" + std::to_string(ledger->seq()), [this, ledger]() { update(ledger); });
     }
 }
 
 void
-OrderBookDB::update(std::shared_ptr<ReadView const> const& ledger)
+OrderBookDBImpl::update(std::shared_ptr<ReadView const> const& ledger)
 {
-    if (app_.config().PATH_SEARCH_MAX == 0)
+    if (pathSearchMax_ == 0)
         return;  // pathfinding has been disabled
 
     // A newer full update job is pending
@@ -79,7 +90,7 @@ OrderBookDB::update(std::shared_ptr<ReadView const> const& ledger)
     {
         for (auto& sle : ledger->sles)
         {
-            if (app_.isStopping())
+            if (registry_.isStopping())
             {
                 JLOG(j_.info()) << "Update halted because the process is stopping";
                 seq_.store(0);
@@ -143,11 +154,11 @@ OrderBookDB::update(std::shared_ptr<ReadView const> const& ledger)
         xrpDomainBooks_.swap(xrpDomainBooks);
     }
 
-    app_.getLedgerMaster().newOrderBookDB();
+    registry_.getLedgerMaster().newOrderBookDB();
 }
 
 void
-OrderBookDB::addOrderBook(Book const& book)
+OrderBookDBImpl::addOrderBook(Book const& book)
 {
     bool toXRP = isXRP(book.out);
 
@@ -166,7 +177,7 @@ OrderBookDB::addOrderBook(Book const& book)
 
 // return list of all orderbooks that want this issuerID and currencyID
 std::vector<Book>
-OrderBookDB::getBooksByTakerPays(Issue const& issue, std::optional<uint256> const& domain)
+OrderBookDBImpl::getBooksByTakerPays(Issue const& issue, std::optional<uint256> const& domain)
 {
     std::vector<Book> ret;
 
@@ -194,7 +205,7 @@ OrderBookDB::getBooksByTakerPays(Issue const& issue, std::optional<uint256> cons
 }
 
 int
-OrderBookDB::getBookSize(Issue const& issue, std::optional<uint256> const& domain)
+OrderBookDBImpl::getBookSize(Issue const& issue, std::optional<uint256> const& domain)
 {
     std::lock_guard sl(mLock);
 
@@ -213,7 +224,7 @@ OrderBookDB::getBookSize(Issue const& issue, std::optional<uint256> const& domai
 }
 
 bool
-OrderBookDB::isBookToXRP(Issue const& issue, std::optional<Domain> domain)
+OrderBookDBImpl::isBookToXRP(Issue const& issue, std::optional<Domain> domain)
 {
     std::lock_guard sl(mLock);
     if (domain)
@@ -222,7 +233,7 @@ OrderBookDB::isBookToXRP(Issue const& issue, std::optional<Domain> domain)
 }
 
 BookListeners::pointer
-OrderBookDB::makeBookListeners(Book const& book)
+OrderBookDBImpl::makeBookListeners(Book const& book)
 {
     std::lock_guard sl(mLock);
     auto ret = getBookListeners(book);
@@ -242,7 +253,7 @@ OrderBookDB::makeBookListeners(Book const& book)
 }
 
 BookListeners::pointer
-OrderBookDB::getBookListeners(Book const& book)
+OrderBookDBImpl::getBookListeners(Book const& book)
 {
     BookListeners::pointer ret;
     std::lock_guard sl(mLock);
@@ -257,7 +268,7 @@ OrderBookDB::getBookListeners(Book const& book)
 // Based on the meta, send the meta to the streams that are listening.
 // We need to determine which streams a given meta effects.
 void
-OrderBookDB::processTxn(
+OrderBookDBImpl::processTxn(
     std::shared_ptr<ReadView const> const& ledger,
     AcceptedLedgerTx const& alTx,
     MultiApiJson const& jvObj)
diff --git a/src/xrpld/app/ledger/OrderBookDBImpl.h b/src/xrpld/app/ledger/OrderBookDBImpl.h
new file mode 100644
index 0000000000..69739451c4
--- /dev/null
+++ b/src/xrpld/app/ledger/OrderBookDBImpl.h
@@ -0,0 +1,93 @@
+#pragma once
+
+#include <xrpl/core/ServiceRegistry.h>
+#include <xrpl/ledger/AcceptedLedgerTx.h>
+#include <xrpl/ledger/BookListeners.h>
+#include <xrpl/ledger/OrderBookDB.h>
+#include <xrpl/protocol/MultiApiJson.h>
+#include <xrpl/protocol/UintTypes.h>
+
+#include <mutex>
+#include <optional>
+
+namespace xrpl {
+
+/** Configuration for OrderBookDB */
+struct OrderBookDBConfig
+{
+    int pathSearchMax;
+    bool standalone;
+};
+
+/** Create an OrderBookDB instance.
+
+    @param registry Service registry for accessing other services
+    @param config Configuration parameters
+    @return A new OrderBookDB instance
+*/
+std::unique_ptr<OrderBookDB>
+make_OrderBookDB(ServiceRegistry& registry, OrderBookDBConfig const& config);
+
+class OrderBookDBImpl final : public OrderBookDB
+{
+public:
+    OrderBookDBImpl(ServiceRegistry& registry, OrderBookDBConfig const& config);
+
+    // OrderBookDB interface implementation
+    void
+    setup(std::shared_ptr<ReadView const> const& ledger) override;
+
+    void
+    addOrderBook(Book const& book) override;
+
+    std::vector<Book>
+    getBooksByTakerPays(Issue const& issue, std::optional<Domain> const& domain = std::nullopt) override;
+
+    int
+    getBookSize(Issue const& issue, std::optional<Domain> const& domain = std::nullopt) override;
+
+    bool
+    isBookToXRP(Issue const& issue, std::optional<Domain> domain = std::nullopt) override;
+
+    // OrderBookDBImpl-specific methods
+    void
+    update(std::shared_ptr<ReadView const> const& ledger);
+
+    // see if this txn effects any orderbook
+    void
+    processTxn(std::shared_ptr<ReadView const> const& ledger, AcceptedLedgerTx const& alTx, MultiApiJson const& jvObj)
+        override;
+
+    BookListeners::pointer
+    getBookListeners(Book const&) override;
+    BookListeners::pointer
+    makeBookListeners(Book const&) override;
+
+private:
+    ServiceRegistry& registry_;
+    int const pathSearchMax_;
+    bool const standalone_;
+
+    // Maps order books by "issue in" to "issue out":
+    hardened_hash_map<Issue, hardened_hash_set<Issue>> allBooks_;
+
+    hardened_hash_map<std::pair<Issue, Domain>, hardened_hash_set<Issue>> domainBooks_;
+
+    // does an order book to XRP exist
+    hash_set<Issue> xrpBooks_;
+
+    // does an order book to XRP exist
+    hash_set<std::pair<Issue, Domain>> xrpDomainBooks_;
+
+    std::recursive_mutex mLock;
+
+    using BookToListenersMap = hash_map<Book, BookListeners::pointer>;
+
+    BookToListenersMap mListeners;
+
+    std::atomic<std::uint32_t> seq_;
+
+    beast::Journal const j_;
+};
+
+}  // namespace xrpl
diff --git a/src/xrpld/app/ledger/detail/LedgerMaster.cpp b/src/xrpld/app/ledger/detail/LedgerMaster.cpp
index f8ef91a83f..5538ebcb96 100644
--- a/src/xrpld/app/ledger/detail/LedgerMaster.cpp
+++ b/src/xrpld/app/ledger/detail/LedgerMaster.cpp
@@ -3,7 +3,6 @@
 #include <xrpld/app/ledger/LedgerMaster.h>
 #include <xrpld/app/ledger/LedgerReplayer.h>
 #include <xrpld/app/ledger/OpenLedger.h>
-#include <xrpld/app/ledger/OrderBookDB.h>
 #include <xrpld/app/ledger/PendingSaves.h>
 #include <xrpld/app/main/Application.h>
 #include <xrpld/app/misc/AmendmentTable.h>
@@ -24,6 +23,7 @@
 #include <xrpl/basics/safe_cast.h>
 #include <xrpl/basics/scope.h>
 #include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/protocol/BuildInfo.h>
 #include <xrpl/protocol/HashPrefix.h>
 #include <xrpl/protocol/digest.h>
diff --git a/src/xrpld/app/ledger/detail/OpenLedger.cpp b/src/xrpld/app/ledger/detail/OpenLedger.cpp
index 698862d4da..d621285619 100644
--- a/src/xrpld/app/ledger/detail/OpenLedger.cpp
+++ b/src/xrpld/app/ledger/detail/OpenLedger.cpp
@@ -1,11 +1,11 @@
 #include <xrpld/app/ledger/OpenLedger.h>
 #include <xrpld/app/main/Application.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/TxQ.h>
 #include <xrpld/app/tx/apply.h>
 #include <xrpld/overlay/Message.h>
 #include <xrpld/overlay/Overlay.h>
 
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/ledger/CachedView.h>
 #include <xrpl/protocol/TxFlags.h>
 
diff --git a/src/xrpld/app/main/Application.cpp b/src/xrpld/app/main/Application.cpp
index 3f7b6c5596..4612479b78 100644
--- a/src/xrpld/app/main/Application.cpp
+++ b/src/xrpld/app/main/Application.cpp
@@ -6,7 +6,7 @@
 #include <xrpld/app/ledger/LedgerReplayer.h>
 #include <xrpld/app/ledger/LedgerToJson.h>
 #include <xrpld/app/ledger/OpenLedger.h>
-#include <xrpld/app/ledger/OrderBookDB.h>
+#include <xrpld/app/ledger/OrderBookDBImpl.h>
 #include <xrpld/app/ledger/PendingSaves.h>
 #include <xrpld/app/ledger/TransactionMaster.h>
 #include <xrpld/app/main/Application.h>
@@ -16,13 +16,13 @@
 #include <xrpld/app/main/NodeIdentity.h>
 #include <xrpld/app/main/NodeStoreScheduler.h>
 #include <xrpld/app/misc/AmendmentTable.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
 #include <xrpld/app/misc/SHAMapStore.h>
 #include <xrpld/app/misc/TxQ.h>
 #include <xrpld/app/misc/ValidatorKeys.h>
 #include <xrpld/app/misc/ValidatorSite.h>
 #include <xrpld/app/misc/make_NetworkOPs.h>
+#include <xrpld/app/misc/setup_HashRouter.h>
 #include <xrpld/app/paths/PathRequests.h>
 #include <xrpld/app/rdb/backend/SQLiteDatabase.h>
 #include <xrpld/app/tx/apply.h>
@@ -36,6 +36,7 @@
 #include <xrpl/basics/random.h>
 #include <xrpl/beast/asio/io_latency_probe.h>
 #include <xrpl/beast/core/LexicalCast.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/core/PeerReservationTable.h>
 #include <xrpl/core/PerfLog.h>
 #include <xrpl/crypto/csprng.h>
@@ -164,8 +165,7 @@ public:
 
     std::unique_ptr<NodeStore::Database> m_nodeStore;
     NodeFamily nodeFamily_;
-    // VFALCO TODO Make OrderBookDB abstract
-    OrderBookDB m_orderBookDB;
+    std::unique_ptr<OrderBookDB> m_orderBookDB;
     std::unique_ptr<PathRequests> m_pathRequests;
     std::unique_ptr<LedgerMaster> m_ledgerMaster;
     std::unique_ptr<LedgerCleaner> ledgerCleaner_;
@@ -296,7 +296,7 @@ public:
 
         , nodeFamily_(*this, *m_collectorManager)
 
-        , m_orderBookDB(*this)
+        , m_orderBookDB(make_OrderBookDB(*this, {config_->PATH_SEARCH_MAX, config_->standalone()}))
 
         , m_pathRequests(
               std::make_unique<PathRequests>(*this, logs_->journal("PathRequest"), m_collectorManager->collector()))
@@ -613,7 +613,7 @@ public:
     OrderBookDB&
     getOrderBookDB() override
     {
-        return m_orderBookDB;
+        return *m_orderBookDB;
     }
 
     PathRequests&
@@ -1170,7 +1170,7 @@ ApplicationImp::setup(boost::program_options::variables_map const& cmdline)
         m_ledgerMaster->setLedgerRangePresent(forcedRange->first, forcedRange->second);
     }
 
-    m_orderBookDB.setup(getLedgerMaster().getCurrentLedger());
+    m_orderBookDB->setup(getLedgerMaster().getCurrentLedger());
 
     nodeIdentity_ = getNodeIdentity(*this, cmdline);
 
diff --git a/src/xrpld/app/main/Application.h b/src/xrpld/app/main/Application.h
index 5ecc84c11c..a0fea69171 100644
--- a/src/xrpld/app/main/Application.h
+++ b/src/xrpld/app/main/Application.h
@@ -153,17 +153,10 @@ public:
     virtual int
     fdRequired() const = 0;
 
-    /** Retrieve the "wallet database" */
-    virtual DatabaseCon&
-    getWalletDB() = 0;
-
     /** Ensure that a newly-started validator does not sign proposals older
      * than the last ledger it persisted. */
     virtual LedgerIndex
     getMaxDisallowedLedger() = 0;
-
-    virtual std::optional<uint256> const&
-    trapTxID() const = 0;
 };
 
 std::unique_ptr<Application>
diff --git a/src/xrpld/app/misc/AmendmentTable.h b/src/xrpld/app/misc/AmendmentTable.h
index 94ac9608a7..bfef818b0a 100644
--- a/src/xrpld/app/misc/AmendmentTable.h
+++ b/src/xrpld/app/misc/AmendmentTable.h
@@ -3,6 +3,7 @@
 #include <xrpld/app/ledger/Ledger.h>
 #include <xrpld/core/ConfigSections.h>
 
+#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/STValidation.h>
@@ -163,7 +164,7 @@ public:
 
 std::unique_ptr<AmendmentTable>
 make_AmendmentTable(
-    Application& app,
+    ServiceRegistry& registry,
     std::chrono::seconds majorityTime,
     std::vector<AmendmentTable::FeatureInfo> const& supported,
     Section const& enabled,
diff --git a/src/xrpld/app/misc/NetworkOPs.cpp b/src/xrpld/app/misc/NetworkOPs.cpp
index 9e60a8bdc0..8732f9610d 100644
--- a/src/xrpld/app/misc/NetworkOPs.cpp
+++ b/src/xrpld/app/misc/NetworkOPs.cpp
@@ -7,13 +7,11 @@
 #include <xrpld/app/ledger/LedgerToJson.h>
 #include <xrpld/app/ledger/LocalTxs.h>
 #include <xrpld/app/ledger/OpenLedger.h>
-#include <xrpld/app/ledger/OrderBookDB.h>
 #include <xrpld/app/ledger/TransactionMaster.h>
 #include <xrpld/app/main/LoadManager.h>
 #include <xrpld/app/main/Tuning.h>
 #include <xrpld/app/misc/AmendmentTable.h>
 #include <xrpld/app/misc/DeliverMax.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
 #include <xrpld/app/misc/Transaction.h>
 #include <xrpld/app/misc/TxQ.h>
@@ -39,9 +37,11 @@
 #include <xrpl/basics/safe_cast.h>
 #include <xrpl/basics/scope.h>
 #include <xrpl/beast/utility/rngfill.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/core/PerfLog.h>
 #include <xrpl/crypto/RFC1751.h>
 #include <xrpl/crypto/csprng.h>
+#include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/protocol/BuildInfo.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/MultiApiJson.h>
@@ -2824,7 +2824,7 @@ NetworkOPsImp::pubLedger(std::shared_ptr<ReadView const> const& lpAccepted)
     std::shared_ptr<AcceptedLedger> alpAccepted = registry_.getAcceptedLedgerCache().fetch(lpAccepted->header().hash);
     if (!alpAccepted)
     {
-        alpAccepted = std::make_shared<AcceptedLedger>(lpAccepted, registry_.app());
+        alpAccepted = std::make_shared<AcceptedLedger>(lpAccepted);
         registry_.getAcceptedLedgerCache().canonicalize_replace_client(lpAccepted->header().hash, alpAccepted);
     }
 
diff --git a/src/xrpld/app/misc/detail/AmendmentTable.cpp b/src/xrpld/app/misc/detail/AmendmentTable.cpp
index 3addfd2235..767a3d87f9 100644
--- a/src/xrpld/app/misc/detail/AmendmentTable.cpp
+++ b/src/xrpld/app/misc/detail/AmendmentTable.cpp
@@ -1,7 +1,7 @@
-#include <xrpld/app/main/Application.h>
 #include <xrpld/app/misc/AmendmentTable.h>
 #include <xrpld/core/ConfigSections.h>
 
+#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STValidation.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -400,7 +400,7 @@ private:
 
 public:
     AmendmentTableImpl(
-        Application& app,
+        ServiceRegistry& registry,
         std::chrono::seconds majorityTime,
         std::vector<FeatureInfo> const& supported,
         Section const& enabled,
@@ -461,13 +461,17 @@ public:
 //------------------------------------------------------------------------------
 
 AmendmentTableImpl::AmendmentTableImpl(
-    Application& app,
+    ServiceRegistry& registry,
     std::chrono::seconds majorityTime,
     std::vector<FeatureInfo> const& supported,
     Section const& enabled,
     Section const& vetoed,
     beast::Journal journal)
-    : lastUpdateSeq_(0), majorityTime_(majorityTime), unsupportedEnabled_(false), j_(journal), db_(app.getWalletDB())
+    : lastUpdateSeq_(0)
+    , majorityTime_(majorityTime)
+    , unsupportedEnabled_(false)
+    , j_(journal)
+    , db_(registry.getWalletDB())
 {
     std::lock_guard lock(mutex_);
 
@@ -957,14 +961,14 @@ AmendmentTableImpl::getJson(uint256 const& amendmentID, bool isAdmin) const
 
 std::unique_ptr<AmendmentTable>
 make_AmendmentTable(
-    Application& app,
+    ServiceRegistry& registry,
     std::chrono::seconds majorityTime,
     std::vector<AmendmentTable::FeatureInfo> const& supported,
     Section const& enabled,
     Section const& vetoed,
     beast::Journal journal)
 {
-    return std::make_unique<AmendmentTableImpl>(app, majorityTime, supported, enabled, vetoed, journal);
+    return std::make_unique<AmendmentTableImpl>(registry, majorityTime, supported, enabled, vetoed, journal);
 }
 
 }  // namespace xrpl
diff --git a/src/xrpld/app/misc/detail/Transaction.cpp b/src/xrpld/app/misc/detail/Transaction.cpp
index 8ffbc47b08..d45c49c3c4 100644
--- a/src/xrpld/app/misc/detail/Transaction.cpp
+++ b/src/xrpld/app/misc/detail/Transaction.cpp
@@ -1,11 +1,11 @@
 #include <xrpld/app/ledger/LedgerMaster.h>
 #include <xrpld/app/main/Application.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/Transaction.h>
 #include <xrpld/app/tx/apply.h>
 #include <xrpld/rpc/CTID.h>
 
 #include <xrpl/basics/safe_cast.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 #include <xrpl/rdb/RelationalDatabase.h>
diff --git a/src/xrpld/app/misc/detail/ValidatorList.cpp b/src/xrpld/app/misc/detail/ValidatorList.cpp
index 3a46d2baa1..4730df4983 100644
--- a/src/xrpld/app/misc/detail/ValidatorList.cpp
+++ b/src/xrpld/app/misc/detail/ValidatorList.cpp
@@ -1,4 +1,3 @@
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/ValidatorList.h>
 #include <xrpld/overlay/Overlay.h>
 
@@ -6,6 +5,7 @@
 #include <xrpl/basics/Slice.h>
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/basics/base64.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/json/json_reader.h>
 #include <xrpl/protocol/PublicKey.h>
 #include <xrpl/protocol/STValidation.h>
diff --git a/src/xrpld/app/misc/detail/setup_HashRouter.cpp b/src/xrpld/app/misc/detail/setup_HashRouter.cpp
new file mode 100644
index 0000000000..a0e63dd67e
--- /dev/null
+++ b/src/xrpld/app/misc/detail/setup_HashRouter.cpp
@@ -0,0 +1,42 @@
+#include <xrpld/app/misc/setup_HashRouter.h>
+#include <xrpld/core/Config.h>
+
+#include <xrpl/basics/BasicConfig.h>
+
+namespace xrpl {
+
+HashRouter::Setup
+setup_HashRouter(Config const& config)
+{
+    using namespace std::chrono;
+
+    HashRouter::Setup setup;
+    auto const& section = config.section("hashrouter");
+
+    std::int32_t tmp{};
+
+    if (set(tmp, "hold_time", section))
+    {
+        if (tmp < 12)
+            Throw<std::runtime_error>(
+                "HashRouter hold time must be at least 12 seconds (the "
+                "approximate validation time for three ledgers).");
+        setup.holdTime = seconds(tmp);
+    }
+    if (set(tmp, "relay_time", section))
+    {
+        if (tmp < 8)
+            Throw<std::runtime_error>(
+                "HashRouter relay time must be at least 8 seconds (the "
+                "approximate validation time for two ledgers).");
+        setup.relayTime = seconds(tmp);
+    }
+    if (setup.relayTime > setup.holdTime)
+    {
+        Throw<std::runtime_error>("HashRouter relay time must be less than or equal to hold time");
+    }
+
+    return setup;
+}
+
+}  // namespace xrpl
diff --git a/src/xrpld/app/misc/setup_HashRouter.h b/src/xrpld/app/misc/setup_HashRouter.h
new file mode 100644
index 0000000000..3054233b89
--- /dev/null
+++ b/src/xrpld/app/misc/setup_HashRouter.h
@@ -0,0 +1,17 @@
+#ifndef XRPLD_APP_MISC_SETUP_HASHROUTER_H_INCLUDED
+#define XRPLD_APP_MISC_SETUP_HASHROUTER_H_INCLUDED
+
+#include <xrpl/core/HashRouter.h>
+
+namespace xrpl {
+
+// Forward declaration
+class Config;
+
+/** Create HashRouter setup from configuration */
+HashRouter::Setup
+setup_HashRouter(Config const& config);
+
+}  // namespace xrpl
+
+#endif
diff --git a/src/xrpld/app/paths/Pathfinder.cpp b/src/xrpld/app/paths/Pathfinder.cpp
index b64ce0cc20..ea4fa2013a 100644
--- a/src/xrpld/app/paths/Pathfinder.cpp
+++ b/src/xrpld/app/paths/Pathfinder.cpp
@@ -1,4 +1,3 @@
-#include <xrpld/app/ledger/OrderBookDB.h>
 #include <xrpld/app/main/Application.h>
 #include <xrpld/app/paths/Pathfinder.h>
 #include <xrpld/app/paths/RippleCalc.h>
@@ -9,6 +8,7 @@
 #include <xrpl/basics/join.h>
 #include <xrpl/core/JobQueue.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/ledger/PaymentSandbox.h>
 
 #include <tuple>
diff --git a/src/xrpld/app/rdb/backend/detail/Node.cpp b/src/xrpld/app/rdb/backend/detail/Node.cpp
index 328d07c0ab..01e036731c 100644
--- a/src/xrpld/app/rdb/backend/detail/Node.cpp
+++ b/src/xrpld/app/rdb/backend/detail/Node.cpp
@@ -203,7 +203,7 @@ saveValidatedLedger(
         aLedger = app.getAcceptedLedgerCache().fetch(ledger->header().hash);
         if (!aLedger)
         {
-            aLedger = std::make_shared<AcceptedLedger>(ledger, app);
+            aLedger = std::make_shared<AcceptedLedger>(ledger);
             app.getAcceptedLedgerCache().canonicalize_replace_client(ledger->header().hash, aLedger);
         }
     }
diff --git a/src/xrpld/app/tx/detail/AMMCreate.cpp b/src/xrpld/app/tx/detail/AMMCreate.cpp
index 4634ac79e0..aa75a18e30 100644
--- a/src/xrpld/app/tx/detail/AMMCreate.cpp
+++ b/src/xrpld/app/tx/detail/AMMCreate.cpp
@@ -1,8 +1,8 @@
-#include <xrpld/app/ledger/OrderBookDB.h>
 #include <xrpld/app/misc/AMMHelpers.h>
 #include <xrpld/app/misc/AMMUtils.h>
 #include <xrpld/app/tx/detail/AMMCreate.h>
 
+#include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/ledger/Sandbox.h>
 #include <xrpl/ledger/View.h>
 #include <xrpl/protocol/AMMCore.h>
diff --git a/src/xrpld/app/tx/detail/Batch.cpp b/src/xrpld/app/tx/detail/Batch.cpp
index 34b08beb2f..81f39193cb 100644
--- a/src/xrpld/app/tx/detail/Batch.cpp
+++ b/src/xrpld/app/tx/detail/Batch.cpp
@@ -6,6 +6,7 @@
 #include <xrpl/ledger/View.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/SystemParameters.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/TxFlags.h>
 
diff --git a/src/xrpld/app/tx/detail/Batch.h b/src/xrpld/app/tx/detail/Batch.h
index 8af8b2e020..17abec38c3 100644
--- a/src/xrpld/app/tx/detail/Batch.h
+++ b/src/xrpld/app/tx/detail/Batch.h
@@ -1,7 +1,6 @@
 #pragma once
 
 #include <xrpld/app/tx/detail/Transactor.h>
-#include <xrpld/core/Config.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/protocol/Indexes.h>
diff --git a/src/xrpld/app/tx/detail/CancelCheck.cpp b/src/xrpld/app/tx/detail/CancelCheck.cpp
index 4ac04e9ffb..086a126eb4 100644
--- a/src/xrpld/app/tx/detail/CancelCheck.cpp
+++ b/src/xrpld/app/tx/detail/CancelCheck.cpp
@@ -1,8 +1,8 @@
-#include <xrpld/app/ledger/Ledger.h>
 #include <xrpld/app/tx/detail/CancelCheck.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/View.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TER.h>
diff --git a/src/xrpld/app/tx/detail/CashCheck.cpp b/src/xrpld/app/tx/detail/CashCheck.cpp
index 9deee006d9..2cc25924a1 100644
--- a/src/xrpld/app/tx/detail/CashCheck.cpp
+++ b/src/xrpld/app/tx/detail/CashCheck.cpp
@@ -1,9 +1,9 @@
-#include <xrpld/app/ledger/Ledger.h>
 #include <xrpld/app/paths/Flow.h>
 #include <xrpld/app/tx/detail/CashCheck.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/scope.h>
+#include <xrpl/ledger/View.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TER.h>
diff --git a/src/xrpld/app/tx/detail/CreateOffer.cpp b/src/xrpld/app/tx/detail/CreateOffer.cpp
index fab406189b..666023233d 100644
--- a/src/xrpld/app/tx/detail/CreateOffer.cpp
+++ b/src/xrpld/app/tx/detail/CreateOffer.cpp
@@ -1,10 +1,10 @@
-#include <xrpld/app/ledger/OrderBookDB.h>
 #include <xrpld/app/misc/PermissionedDEXHelpers.h>
 #include <xrpld/app/paths/Flow.h>
 #include <xrpld/app/tx/detail/CreateOffer.h>
 
 #include <xrpl/basics/base_uint.h>
 #include <xrpl/beast/utility/WrappedSink.h>
+#include <xrpl/ledger/OrderBookDB.h>
 #include <xrpl/ledger/PaymentSandbox.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STAmount.h>
diff --git a/src/xrpld/app/tx/detail/CreateTicket.cpp b/src/xrpld/app/tx/detail/CreateTicket.cpp
index e6965ca1cf..eb42904a0b 100644
--- a/src/xrpld/app/tx/detail/CreateTicket.cpp
+++ b/src/xrpld/app/tx/detail/CreateTicket.cpp
@@ -1,6 +1,7 @@
 #include <xrpld/app/tx/detail/CreateTicket.h>
 
 #include <xrpl/basics/Log.h>
+#include <xrpl/ledger/View.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/TxFlags.h>
diff --git a/src/xrpld/app/tx/detail/CreateTicket.h b/src/xrpld/app/tx/detail/CreateTicket.h
index 2a6e1bb8cc..dd424e3756 100644
--- a/src/xrpld/app/tx/detail/CreateTicket.h
+++ b/src/xrpld/app/tx/detail/CreateTicket.h
@@ -1,6 +1,5 @@
 #pragma once
 
-#include <xrpld/app/ledger/Ledger.h>
 #include <xrpld/app/tx/detail/Transactor.h>
 
 namespace xrpl {
diff --git a/src/xrpld/app/tx/detail/Escrow.cpp b/src/xrpld/app/tx/detail/Escrow.cpp
index 80d1f6c9da..dea9d3aa2b 100644
--- a/src/xrpld/app/tx/detail/Escrow.cpp
+++ b/src/xrpld/app/tx/detail/Escrow.cpp
@@ -1,11 +1,11 @@
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/tx/detail/Escrow.h>
 #include <xrpld/app/tx/detail/MPTokenAuthorize.h>
-#include <xrpld/conditions/Condition.h>
-#include <xrpld/conditions/Fulfillment.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/chrono.h>
+#include <xrpl/conditions/Condition.h>
+#include <xrpl/conditions/Fulfillment.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/CredentialHelpers.h>
 #include <xrpl/ledger/View.h>
diff --git a/src/xrpld/app/tx/detail/SetAccount.cpp b/src/xrpld/app/tx/detail/SetAccount.cpp
index beca60c06b..41804c9211 100644
--- a/src/xrpld/app/tx/detail/SetAccount.cpp
+++ b/src/xrpld/app/tx/detail/SetAccount.cpp
@@ -1,6 +1,5 @@
 #include <xrpld/app/misc/DelegateUtils.h>
 #include <xrpld/app/tx/detail/SetAccount.h>
-#include <xrpld/core/Config.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/ledger/View.h>
diff --git a/src/xrpld/app/tx/detail/Transactor.cpp b/src/xrpld/app/tx/detail/Transactor.cpp
index b3b5d8b9bc..a7bb7992fb 100644
--- a/src/xrpld/app/tx/detail/Transactor.cpp
+++ b/src/xrpld/app/tx/detail/Transactor.cpp
@@ -1,11 +1,9 @@
-#include <xrpld/app/main/Application.h>
 #include <xrpld/app/misc/DelegateUtils.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
 #include <xrpld/app/tx/apply.h>
 #include <xrpld/app/tx/detail/NFTokenUtils.h>
 #include <xrpld/app/tx/detail/SignerEntries.h>
 #include <xrpld/app/tx/detail/Transactor.h>
-#include <xrpld/core/Config.h>
 
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/contract.h>
@@ -15,6 +13,7 @@
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>
+#include <xrpl/protocol/SystemParameters.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/UintTypes.h>
 
diff --git a/src/xrpld/app/tx/detail/apply.cpp b/src/xrpld/app/tx/detail/apply.cpp
index 7babc415d5..1c7a509007 100644
--- a/src/xrpld/app/tx/detail/apply.cpp
+++ b/src/xrpld/app/tx/detail/apply.cpp
@@ -1,8 +1,9 @@
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/tx/apply.h>
 #include <xrpld/app/tx/applySteps.h>
 
 #include <xrpl/basics/Log.h>
+#include <xrpl/core/HashRouter.h>
+#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/TxFlags.h>
 
diff --git a/src/xrpld/overlay/detail/OverlayImpl.cpp b/src/xrpld/overlay/detail/OverlayImpl.cpp
index ceefab24f1..5b9f142001 100644
--- a/src/xrpld/overlay/detail/OverlayImpl.cpp
+++ b/src/xrpld/overlay/detail/OverlayImpl.cpp
@@ -1,4 +1,3 @@
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/ValidatorList.h>
 #include <xrpld/app/misc/ValidatorSite.h>
 #include <xrpld/overlay/Cluster.h>
@@ -15,6 +14,7 @@
 #include <xrpl/basics/make_SSLContext.h>
 #include <xrpl/basics/random.h>
 #include <xrpl/beast/core/LexicalCast.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/STTx.h>
 #include <xrpl/rdb/RelationalDatabase.h>
 #include <xrpl/server/NetworkOPs.h>
diff --git a/src/xrpld/overlay/detail/PeerImp.cpp b/src/xrpld/overlay/detail/PeerImp.cpp
index d66a57bae6..ec641487a8 100644
--- a/src/xrpld/overlay/detail/PeerImp.cpp
+++ b/src/xrpld/overlay/detail/PeerImp.cpp
@@ -3,7 +3,6 @@
 #include <xrpld/app/ledger/InboundTransactions.h>
 #include <xrpld/app/ledger/LedgerMaster.h>
 #include <xrpld/app/ledger/TransactionMaster.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
 #include <xrpld/app/misc/Transaction.h>
 #include <xrpld/app/misc/ValidatorList.h>
@@ -16,6 +15,7 @@
 #include <xrpl/basics/base64.h>
 #include <xrpl/basics/random.h>
 #include <xrpl/basics/safe_cast.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/core/PerfLog.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/digest.h>
diff --git a/src/xrpld/overlay/detail/PeerImp.h b/src/xrpld/overlay/detail/PeerImp.h
index 65a6112159..d88314a9a5 100644
--- a/src/xrpld/overlay/detail/PeerImp.h
+++ b/src/xrpld/overlay/detail/PeerImp.h
@@ -2,7 +2,6 @@
 
 #include <xrpld/app/consensus/RCLCxPeerPos.h>
 #include <xrpld/app/ledger/detail/LedgerReplayMsgHandler.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/overlay/Squelch.h>
 #include <xrpld/overlay/detail/OverlayImpl.h>
 #include <xrpld/overlay/detail/ProtocolVersion.h>
@@ -11,6 +10,7 @@
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/UnorderedContainers.h>
 #include <xrpl/beast/utility/WrappedSink.h>
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/Protocol.h>
 #include <xrpl/protocol/STTx.h>
 #include <xrpl/protocol/STValidation.h>
diff --git a/src/xrpld/rpc/handlers/Simulate.cpp b/src/xrpld/rpc/handlers/Simulate.cpp
index f44fc57261..58b40e2048 100644
--- a/src/xrpld/rpc/handlers/Simulate.cpp
+++ b/src/xrpld/rpc/handlers/Simulate.cpp
@@ -1,6 +1,5 @@
 #include <xrpld/app/ledger/LedgerMaster.h>
 #include <xrpld/app/ledger/OpenLedger.h>
-#include <xrpld/app/misc/HashRouter.h>
 #include <xrpld/app/misc/Transaction.h>
 #include <xrpld/app/misc/TxQ.h>
 #include <xrpld/app/tx/apply.h>
@@ -10,6 +9,7 @@
 #include <xrpld/rpc/MPTokenIssuanceID.h>
 #include <xrpld/rpc/detail/TransactionSign.h>
 
+#include <xrpl/core/HashRouter.h>
 #include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/NFTSyntheticSerializer.h>
 #include <xrpl/protocol/RPCErr.h>