diff --git a/.clang-tidy b/.clang-tidy
index 3bad686a11..a79b565e59 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -66,29 +66,9 @@ Checks: "-*,
   modernize-*,
   -modernize-avoid-c-arrays,
   -modernize-avoid-c-style-cast,
-  -modernize-avoid-setjmp-longjmp,
-  -modernize-avoid-variadic-functions,
-  -modernize-deprecated-ios-base-aliases,
-  -modernize-loop-convert,
-  -modernize-macro-to-enum,
-  -modernize-min-max-use-initializer-list,
-  -modernize-raw-string-literal,
-  -modernize-redundant-void-arg,
-  -modernize-replace-auto-ptr,
-  -modernize-replace-disallow-copy-and-assign-macro,
-  -modernize-replace-random-shuffle,
   -modernize-return-braced-init-list,
-  -modernize-shrink-to-fit,
-  -modernize-use-bool-literals,
-  -modernize-use-default-member-init,
   -modernize-use-integer-sign-comparison,
-  -modernize-use-noexcept,
-  -modernize-use-nullptr,
-  -modernize-use-std-format,
-  -modernize-use-std-print,
   -modernize-use-trailing-return-type,
-  -modernize-use-transparent-functors,
-  -modernize-use-uncaught-exceptions,
 
   performance-*,
   -performance-avoid-endl,
diff --git a/include/xrpl/basics/comparators.h b/include/xrpl/basics/comparators.h
deleted file mode 100644
index 0e21d38d6b..0000000000
--- a/include/xrpl/basics/comparators.h
+++ /dev/null
@@ -1,54 +0,0 @@
-#pragma once
-
-#include <functional>
-
-namespace xrpl {
-
-#ifdef _MSC_VER
-
-/*
- * MSVC 2019 version 16.9.0 added [[nodiscard]] to the std comparison
- * operator() functions. boost::bimap checks that the comparator is a
- * BinaryFunction, in part by calling the function and ignoring the value.
- * These two things don't play well together. These wrapper classes simply
- * strip [[nodiscard]] from operator() for use in boost::bimap.
- *
- * See also:
- *  https://www.boost.org/doc/libs/1_75_0/libs/bimap/doc/html/boost_bimap/the_tutorial/controlling_collection_types.html
- */
-
-template <class T = void>
-struct less
-{
-    using result_type = bool;
-
-    constexpr bool
-    operator()(T const& left, T const& right) const
-    {
-        return std::less<T>()(left, right);
-    }
-};
-
-template <class T = void>
-struct equal_to
-{
-    using result_type = bool;
-
-    constexpr bool
-    operator()(T const& left, T const& right) const
-    {
-        return std::equal_to<T>()(left, right);
-    }
-};
-
-#else
-
-template <class T = void>
-using less = std::less<T>;
-
-template <class T = void>
-using equal_to = std::equal_to<T>;
-
-#endif
-
-}  // namespace xrpl
diff --git a/include/xrpl/beast/hash/hash_append.h b/include/xrpl/beast/hash/hash_append.h
index da499dc612..3592ffbfe8 100644
--- a/include/xrpl/beast/hash/hash_append.h
+++ b/include/xrpl/beast/hash/hash_append.h
@@ -392,36 +392,12 @@ hash_append(Hasher& h, boost::container::flat_set<Key, Compare, Alloc> const& v)
 }
 // tuple
 
-namespace detail {
-
-inline void
-forEachItem(...) noexcept
-{
-}
-
-template <class Hasher, class T>
-inline int
-hashOne(Hasher& h, T const& t) noexcept
-{
-    hash_append(h, t);
-    return 0;
-}
-
-template <class Hasher, class... T, std::size_t... I>
-inline void
-tuple_hash(Hasher& h, std::tuple<T...> const& t, std::index_sequence<I...>) noexcept
-{
-    for_each_item(hash_one(h, std::get<I>(t))...);
-}
-
-}  // namespace detail
-
 template <class Hasher, class... T>
 inline void
 hash_append(Hasher& h, std::tuple<T...> const& t) noexcept
     requires(!IsContiguouslyHashable<std::tuple<T...>, Hasher>::value)
 {
-    detail::tuple_hash(h, t, std::index_sequence_for<T...>{});
+    std::apply([&h](auto const&... item) { (hash_append(h, item), ...); }, t);
 }
 
 // shared_ptr
diff --git a/include/xrpl/core/HashRouter.h b/include/xrpl/core/HashRouter.h
index ef8f24d43c..dad1afb405 100644
--- a/include/xrpl/core/HashRouter.h
+++ b/include/xrpl/core/HashRouter.h
@@ -127,7 +127,7 @@ private:
         }
 
         [[nodiscard]] HashRouterFlags
-        getFlags(void) const
+        getFlags() const
         {
             return flags_;
         }
diff --git a/include/xrpl/json/json_reader.h b/include/xrpl/json/json_reader.h
index c1535bfb55..d1e4ada579 100644
--- a/include/xrpl/json/json_reader.h
+++ b/include/xrpl/json/json_reader.h
@@ -154,7 +154,7 @@ private:
         Location end,
         unsigned int& unicode);
     bool
-    addError(std::string const& message, Token& token, Location extra = 0);
+    addError(std::string const& message, Token& token, Location extra = nullptr);
     bool
     recoverFromError(TokenType skipUntilToken);
     bool
diff --git a/include/xrpl/ledger/OpenView.h b/include/xrpl/ledger/OpenView.h
index de81787906..875909715c 100644
--- a/include/xrpl/ledger/OpenView.h
+++ b/include/xrpl/ledger/OpenView.h
@@ -82,7 +82,7 @@ private:
     using txs_map = std::map<
         key_type,
         TxData,
-        std::less<key_type>,
+        std::less<>,
         boost::container::pmr::polymorphic_allocator<std::pair<key_type const, TxData>>>;
 
     // monotonic_resource_ must outlive `items_`. Make a pointer so it may be
diff --git a/include/xrpl/ledger/detail/RawStateTable.h b/include/xrpl/ledger/detail/RawStateTable.h
index cfa528d355..2e36a42eaf 100644
--- a/include/xrpl/ledger/detail/RawStateTable.h
+++ b/include/xrpl/ledger/detail/RawStateTable.h
@@ -105,7 +105,7 @@ private:
     using items_t = std::map<
         key_type,
         SleAction,
-        std::less<key_type>,
+        std::less<>,
         boost::container::pmr::polymorphic_allocator<std::pair<key_type const, SleAction>>>;
     // monotonic_resource_ must outlive `items_`. Make a pointer so it may be
     // easily moved.
diff --git a/include/xrpl/resource/detail/Logic.h b/include/xrpl/resource/detail/Logic.h
index 6b1c5e7397..78cd0ac36c 100644
--- a/include/xrpl/resource/detail/Logic.h
+++ b/include/xrpl/resource/detail/Logic.h
@@ -351,10 +351,9 @@ public:
             Import& import(iter->second);
             if (iter->second.whenExpires <= elapsed)
             {
-                for (auto itemIter(import.items.begin()); itemIter != import.items.end();
-                     ++itemIter)
+                for (auto& item : import.items)
                 {
-                    itemIter->consumer.entry().remoteBalance -= itemIter->balance;
+                    item.consumer.entry().remoteBalance -= item.balance;
                 }
 
                 iter = importTable_.erase(iter);
diff --git a/include/xrpl/shamap/FullBelowCache.h b/include/xrpl/shamap/FullBelowCache.h
index dc597278df..b6d1142eb4 100644
--- a/include/xrpl/shamap/FullBelowCache.h
+++ b/include/xrpl/shamap/FullBelowCache.h
@@ -103,7 +103,7 @@ public:
 
     /** generation determines whether cached entry is valid */
     std::uint32_t
-    getGeneration(void) const
+    getGeneration() const
     {
         return gen_;
     }
diff --git a/src/libxrpl/json/json_reader.cpp b/src/libxrpl/json/json_reader.cpp
index 45e448c480..a12ec7b565 100644
--- a/src/libxrpl/json/json_reader.cpp
+++ b/src/libxrpl/json/json_reader.cpp
@@ -86,8 +86,8 @@ Reader::parse(char const* beginDoc, char const* endDoc, Value& root)
     begin_ = beginDoc;
     end_ = endDoc;
     current_ = begin_;
-    lastValueEnd_ = 0;
-    lastValue_ = 0;
+    lastValueEnd_ = nullptr;
+    lastValue_ = nullptr;
     errors_.clear();
 
     while (!nodes_.empty())
@@ -908,9 +908,8 @@ Reader::getFormattedErrorMessages() const
 {
     std::string formattedMessage;
 
-    for (auto itError = errors_.begin(); itError != errors_.end(); ++itError)
+    for (auto const& error : errors_)
     {
-        ErrorInfo const& error = *itError;
         formattedMessage += "* " + getLocationLineAndColumn(error.token.start) + "\n";
         formattedMessage += "  " + error.message + "\n";
 
diff --git a/src/libxrpl/json/json_value.cpp b/src/libxrpl/json/json_value.cpp
index 7218b8c6cf..c679e30e16 100644
--- a/src/libxrpl/json/json_value.cpp
+++ b/src/libxrpl/json/json_value.cpp
@@ -90,7 +90,7 @@ static struct DummyValueAllocatorInitializer
 // Notes: index_ indicates if the string was allocated when
 // a string is stored.
 
-Value::CZString::CZString(int index) : cstr_(0), index_(index)
+Value::CZString::CZString(int index) : cstr_(nullptr), index_(index)
 {
 }
 
@@ -103,7 +103,8 @@ Value::CZString::CZString(char const* cstr, DuplicationPolicy allocate)
 
 Value::CZString::CZString(CZString const& other)
     : cstr_(
-          other.index_ != static_cast<int>(DuplicationPolicy::NoDuplication) && other.cstr_ != 0
+          other.index_ != static_cast<int>(DuplicationPolicy::NoDuplication) &&
+                  other.cstr_ != nullptr
               ? valueAllocator()->makeMemberName(other.cstr_)
               : other.cstr_)
     , index_([&]() -> int {
@@ -187,7 +188,7 @@ Value::Value(ValueType type) : type_(type)
             break;
 
         case ValueType::String:
-            value_.stringVal = 0;
+            value_.stringVal = nullptr;
             break;
 
         case ValueType::Array:
@@ -268,7 +269,7 @@ Value::Value(Value const& other) : type_(other.type_)
             }
             else
             {
-                value_.stringVal = 0;
+                value_.stringVal = nullptr;
             }
 
             break;
@@ -405,7 +406,7 @@ operator<(Value const& x, Value const& y)
             return static_cast<int>(x.value_.boolVal) < static_cast<int>(y.value_.boolVal);
 
         case ValueType::String:
-            return (x.value_.stringVal == 0 && (y.value_.stringVal != nullptr)) ||
+            return (x.value_.stringVal == nullptr && (y.value_.stringVal != nullptr)) ||
                 ((y.value_.stringVal != nullptr) && (x.value_.stringVal != nullptr) &&
                  strcmp(x.value_.stringVal, y.value_.stringVal) < 0);
 
diff --git a/src/libxrpl/net/HTTPClient.cpp b/src/libxrpl/net/HTTPClient.cpp
index 7294633964..5edd8b5b47 100644
--- a/src/libxrpl/net/HTTPClient.cpp
+++ b/src/libxrpl/net/HTTPClient.cpp
@@ -370,10 +370,10 @@ public:
             {std::istreambuf_iterator<char>(&header_)}, std::istreambuf_iterator<char>()};
         JLOG(j_.trace()) << "Header: \"" << strHeader << "\"";
 
-        static boost::regex const kReStatus{"\\`HTTP/1\\S+ (\\d{3}) .*\\'"};  // HTTP/1.1 200 OK
+        static boost::regex const kReStatus{R"(\`HTTP/1\S+ (\d{3}) .*\')"};  // HTTP/1.1 200 OK
         static boost::regex const kReSize{
-            "\\`.*\\r\\nContent-Length:\\s+([0-9]+).*\\'", boost::regex::icase};
-        static boost::regex const kReBody{"\\`.*\\r\\n\\r\\n(.*)\\'"};
+            R"(\`.*\r\nContent-Length:\s+([0-9]+).*\')", boost::regex::icase};
+        static boost::regex const kReBody{R"(\`.*\r\n\r\n(.*)\')"};
 
         boost::smatch smMatch;
         // Match status code.
diff --git a/src/libxrpl/protocol/PublicKey.cpp b/src/libxrpl/protocol/PublicKey.cpp
index c6e6c1d324..97948fcae3 100644
--- a/src/libxrpl/protocol/PublicKey.cpp
+++ b/src/libxrpl/protocol/PublicKey.cpp
@@ -87,11 +87,11 @@ sliceToHex(Slice const& slice)
         s.reserve(2 * (slice.size() + 1));
         s = "0x";
     }
-    for (int i = 0; i < slice.size(); ++i)
+    for (std::uint8_t const byte : slice)
     {
         static constexpr char kHex[] = "0123456789ABCDEF";
-        s += kHex[((slice[i] & 0xf0) >> 4)];
-        s += kHex[((slice[i] & 0x0f) >> 0)];
+        s += kHex[((byte & 0xf0) >> 4)];
+        s += kHex[((byte & 0x0f) >> 0)];
     }
     return s;
 }
diff --git a/src/libxrpl/protocol/STObject.cpp b/src/libxrpl/protocol/STObject.cpp
index ea8553dc4f..869700baed 100644
--- a/src/libxrpl/protocol/STObject.cpp
+++ b/src/libxrpl/protocol/STObject.cpp
@@ -502,7 +502,7 @@ STObject::isFlag(std::uint32_t f) const
 }
 
 std::uint32_t
-STObject::getFlags(void) const
+STObject::getFlags() const
 {
     auto const* t = dynamic_cast<STUInt32 const*>(peekAtPField(sfFlags));
 
diff --git a/src/libxrpl/protocol/tokens.cpp b/src/libxrpl/protocol/tokens.cpp
index 6716b1185f..21984c67e7 100644
--- a/src/libxrpl/protocol/tokens.cpp
+++ b/src/libxrpl/protocol/tokens.cpp
@@ -23,6 +23,7 @@
 #include <cstdint>
 #include <cstring>
 #include <expected>
+#include <ranges>
 #include <span>
 #include <string>
 #include <string_view>
@@ -265,17 +266,17 @@ decodeBase58(std::string const& s)
 
     // Allocate enough space in big-endian base256 representation.
     // log(58) / log(256), rounded up.
-    std::vector<unsigned char> b256((remain * 733 / 1000) + 1);
+    std::vector<std::uint8_t> b256((remain * 733 / 1000) + 1);
     while (remain > 0)
     {
         auto carry = kAlphabetReverse[*psz];
         if (carry == -1)
             return {};
         // Apply "b256 = b256 * 58 + carry".
-        for (auto iter = b256.rbegin(); iter != b256.rend(); ++iter)
+        for (std::uint8_t& byte : std::views::reverse(b256))
         {
-            carry += 58 * *iter;
-            *iter = carry % 256;
+            carry += 58 * byte;
+            byte = carry % 256;
             carry /= 256;
         }
         XRPL_ASSERT(carry == 0, "xrpl::b58_ref::detail::decodeBase58 : zero carry");
@@ -283,7 +284,7 @@ decodeBase58(std::string const& s)
         --remain;
     }
     // Skip leading zeroes in b256.
-    auto iter = std::ranges::find_if(b256, [](unsigned char c) { return c != 0; });
+    auto iter = std::ranges::find_if(b256, [](std::uint8_t c) { return c != 0; });
     std::string result;
     result.reserve(zeroes + (b256.end() - iter));
     result.assign(zeroes, 0x00);
diff --git a/src/test/app/AMMMPT_test.cpp b/src/test/app/AMMMPT_test.cpp
index c68270591a..4877406ca1 100644
--- a/src/test/app/AMMMPT_test.cpp
+++ b/src/test/app/AMMMPT_test.cpp
@@ -3482,8 +3482,8 @@ private:
             // The vote is not added to the slots
             ammAlice.vote(carol_, 1'000);
             auto const info = ammAlice.ammRpcInfo()[jss::amm][jss::vote_slots];
-            for (auto i = 0; i < info.size(); ++i)
-                BEAST_EXPECT(info[i][jss::account] != carol_.human());
+            for (auto const& entry : info)
+                BEAST_EXPECT(entry[jss::account] != carol_.human());
             // But the slots are refreshed and the fee is changed
             BEAST_EXPECT(ammAlice.expectTradingFee(82));
         }
@@ -6270,7 +6270,7 @@ private:
                 auto const info = env.rpc(
                     "json",
                     "account_info",
-                    std::string("{\"account\": \"" + to_string(amm.ammAccount()) + "\"}"));
+                    std::string(R"({"account": ")" + to_string(amm.ammAccount()) + "\"}"));
                 try
                 {
                     BEAST_EXPECT(
diff --git a/src/test/app/AMM_test.cpp b/src/test/app/AMM_test.cpp
index d4b6ba5429..f19743026c 100644
--- a/src/test/app/AMM_test.cpp
+++ b/src/test/app/AMM_test.cpp
@@ -2463,8 +2463,8 @@ private:
             // The vote is not added to the slots
             ammAlice.vote(carol_, 1'000);
             auto const info = ammAlice.ammRpcInfo()[jss::amm][jss::vote_slots];
-            for (std::uint32_t i = 0; i < info.size(); ++i)
-                BEAST_EXPECT(info[i][jss::account] != carol_.human());
+            for (auto const& entry : info)
+                BEAST_EXPECT(entry[jss::account] != carol_.human());
             // But the slots are refreshed and the fee is changed
             BEAST_EXPECT(ammAlice.expectTradingFee(82));
         });
@@ -4436,7 +4436,7 @@ private:
             auto const info = env.rpc(
                 "json",
                 "account_info",
-                std::string("{\"account\": \"" + to_string(ammAlice.ammAccount()) + "\"}"));
+                std::string(R"({"account": ")" + to_string(ammAlice.ammAccount()) + "\"}"));
             auto const flags = info[jss::result][jss::account_data][jss::Flags].asUInt();
             BEAST_EXPECT(flags == (lsfDisableMaster | lsfDefaultRipple | lsfDepositAuth));
         });
@@ -5265,7 +5265,7 @@ private:
             auto const info = env.rpc(
                 "json",
                 "account_info",
-                std::string("{\"account\": \"" + to_string(amm.ammAccount()) + "\"}"));
+                std::string(R"({"account": ")" + to_string(amm.ammAccount()) + "\"}"));
             try
             {
                 BEAST_EXPECT(
diff --git a/src/test/app/PayChan_test.cpp b/src/test/app/PayChan_test.cpp
index f1a9506e0c..5068472135 100644
--- a/src/test/app/PayChan_test.cpp
+++ b/src/test/app/PayChan_test.cpp
@@ -1323,10 +1323,10 @@ struct PayChan_test : public beast::unit_test::Suite
         auto sliceToHex = [](Slice const& slice) {
             std::string s;
             s.reserve(2 * slice.size());
-            for (int i = 0; i < slice.size(); ++i)
+            for (std::uint8_t const byte : slice)
             {
-                s += "0123456789ABCDEF"[((slice[i] & 0xf0) >> 4)];
-                s += "0123456789ABCDEF"[((slice[i] & 0x0f) >> 0)];
+                s += "0123456789ABCDEF"[((byte & 0xf0) >> 4)];
+                s += "0123456789ABCDEF"[((byte & 0x0f) >> 0)];
             }
             return s;
         };
diff --git a/src/test/app/PermissionedDomains_test.cpp b/src/test/app/PermissionedDomains_test.cpp
index 2cffc18682..784c2b4f56 100644
--- a/src/test/app/PermissionedDomains_test.cpp
+++ b/src/test/app/PermissionedDomains_test.cpp
@@ -289,8 +289,8 @@ class PermissionedDomains_test : public beast::unit_test::Suite
         for (auto const& c : alice)
             human2Acc.emplace(c.human(), c);
 
-        for (int i = 0; i < accNum; ++i)
-            env.fund(XRP(1000), alice[i]);
+        for (auto const& account : alice)
+            env.fund(XRP(1000), account);
 
         // Create new from existing account with a single credential.
         pdomain::Credentials const credentials1{{.issuer = alice[2], .credType = "credential1"}};
diff --git a/src/test/app/ValidatorList_test.cpp b/src/test/app/ValidatorList_test.cpp
index d71554f714..8077c21863 100644
--- a/src/test/app/ValidatorList_test.cpp
+++ b/src/test/app/ValidatorList_test.cpp
@@ -146,8 +146,8 @@ private:
 
         for (auto const& val : validators)
         {
-            data += "{\"validation_public_key\":\"" + strHex(val.masterPublic) +
-                "\",\"manifest\":\"" + val.manifest + "\"},";
+            data += R"({"validation_public_key":")" + strHex(val.masterPublic) +
+                R"(","manifest":")" + val.manifest + "\"},";
         }
 
         data.pop_back();
diff --git a/src/test/basics/Number_test.cpp b/src/test/basics/Number_test.cpp
index 2d2745de14..d704efa27a 100644
--- a/src/test/basics/Number_test.cpp
+++ b/src/test/basics/Number_test.cpp
@@ -17,6 +17,7 @@
 #include <iomanip>
 #include <limits>
 #include <map>
+#include <ranges>
 #include <sstream>
 #include <stdexcept>
 #include <string>
@@ -36,11 +37,11 @@ class Number_test : public beast::unit_test::Suite
         auto s = to_string(value);
         std::string out;
         int count = 0;
-        for (auto it = s.rbegin(); it != s.rend(); ++it)
+        for (char const& ch : std::views::reverse(s))
         {
-            if (count != 0 && count % 3 == 0 && (isdigit(*it) != 0))
+            if (count != 0 && count % 3 == 0 && (isdigit(ch) != 0))
                 out.insert(out.begin(), '_');
-            out.insert(out.begin(), *it);
+            out.insert(out.begin(), ch);
             ++count;
         }
         return out;
diff --git a/src/test/basics/base58_test.cpp b/src/test/basics/base58_test.cpp
index 3c76308813..d2c8d9eabc 100644
--- a/src/test/basics/base58_test.cpp
+++ b/src/test/basics/base58_test.cpp
@@ -10,6 +10,7 @@
 #include <iomanip>
 #include <iostream>
 #include <limits>
+#include <ranges>
 #include <stdexcept>
 #include <string>
 #include <tuple>
@@ -132,10 +133,10 @@ boost::multiprecision::checked_uint512_t
 toBoostMP(std::span<std::uint64_t> in)
 {
     boost::multiprecision::checked_uint512_t mbp = 0;
-    for (auto i = in.rbegin(); i != in.rend(); ++i)
+    for (auto& word : std::views::reverse(in))
     {
         mbp <<= 64;
-        mbp += *i;
+        mbp += word;
     }
     return mbp;
 }
diff --git a/src/test/beast/aged_associative_container_test.cpp b/src/test/beast/aged_associative_container_test.cpp
index 2752ff3127..76be44b793 100644
--- a/src/test/beast/aged_associative_container_test.cpp
+++ b/src/test/beast/aged_associative_container_test.cpp
@@ -145,7 +145,7 @@ public:
         }
 
         T*
-        allocate(std::size_t n, T const* = 0)
+        allocate(std::size_t n, T const* = nullptr)
         {
             return static_cast<T*>(::operator new(n * sizeof(T)));
         }
diff --git a/src/test/core/Config_test.cpp b/src/test/core/Config_test.cpp
index fdac1e450d..38c14b8ac5 100644
--- a/src/test/core/Config_test.cpp
+++ b/src/test/core/Config_test.cpp
@@ -1136,7 +1136,7 @@ trust-these-validators.gov
     testZeroPort()
     {
         auto const contents = std::regex_replace(
-            detail::configContents("", ""), std::regex("port\\s*=\\s*\\d+"), "port = 0");
+            detail::configContents("", ""), std::regex(R"(port\s*=\s*\d+)"), "port = 0");
 
         try
         {
diff --git a/src/test/csf/ledgers.h b/src/test/csf/ledgers.h
index dc5ec5277c..4873519dee 100644
--- a/src/test/csf/ledgers.h
+++ b/src/test/csf/ledgers.h
@@ -3,7 +3,6 @@
 #include <test/csf/Tx.h>
 
 #include <xrpl/basics/chrono.h>
-#include <xrpl/basics/comparators.h>
 #include <xrpl/basics/tagged_integer.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/ledger/LedgerTiming.h>
@@ -13,6 +12,7 @@
 #include <cassert>
 #include <cstddef>
 #include <cstdint>
+#include <functional>
 #include <optional>
 #include <set>
 #include <string>
@@ -232,8 +232,8 @@ private:
 class LedgerOracle
 {
     using InstanceMap = boost::bimaps::bimap<
-        boost::bimaps::set_of<Ledger::Instance, xrpl::less<Ledger::Instance>>,
-        boost::bimaps::set_of<Ledger::ID, xrpl::less<Ledger::ID>>>;
+        boost::bimaps::set_of<Ledger::Instance, std::less<>>,
+        boost::bimaps::set_of<Ledger::ID, std::less<>>>;
     using InstanceEntry = InstanceMap::value_type;
 
     // Set of all known ledgers; note this is never pruned
diff --git a/src/test/jtx/TrustedPublisherServer.h b/src/test/jtx/TrustedPublisherServer.h
index 008bbe70c3..f5ee8aac3a 100644
--- a/src/test/jtx/TrustedPublisherServer.h
+++ b/src/test/jtx/TrustedPublisherServer.h
@@ -188,8 +188,8 @@ public:
 
             for (auto const& val : validators)
             {
-                data += "{\"validation_public_key\":\"" + strHex(val.masterPublic) +
-                    "\",\"manifest\":\"" + val.manifest + "\"},";
+                data += R"({"validation_public_key":")" + strHex(val.masterPublic) +
+                    R"(","manifest":")" + val.manifest + "\"},";
             }
             data.pop_back();
             data += "]}";
@@ -201,8 +201,8 @@ public:
         getList_ = [blob = blob, sig, manifest, version](int interval) {
             // Build the contents of a version 1 format UNL file
             std::stringstream l;
-            l << "{\"blob\":\"" << blob << "\"" << ",\"signature\":\"" << sig << "\""
-              << ",\"manifest\":\"" << manifest << "\""
+            l << R"({"blob":")" << blob << "\"" << R"(,"signature":")" << sig << "\""
+              << R"(,"manifest":")" << manifest << "\""
               << ",\"refresh_interval\": " << interval << ",\"version\":" << version << '}';
             return l.str();
         };
@@ -216,8 +216,8 @@ public:
             // Use the same set of validators for simplicity
             for (auto const& val : validators)
             {
-                data += "{\"validation_public_key\":\"" + strHex(val.masterPublic) +
-                    "\",\"manifest\":\"" + val.manifest + "\"},";
+                data += R"({"validation_public_key":")" + strHex(val.masterPublic) +
+                    R"(","manifest":")" + val.manifest + "\"},";
             }
             data.pop_back();
             data += "]}";
@@ -232,13 +232,13 @@ public:
             std::stringstream l;
             for (auto const& info : blobInfo)
             {
-                l << "{\"blob\":\"" << info.blob << "\"" << ",\"signature\":\"" << info.signature
+                l << R"({"blob":")" << info.blob << "\"" << R"(,"signature":")" << info.signature
                   << "\"},";
             }
             std::string blobs = l.str();
             blobs.pop_back();
             l.str(std::string());
-            l << "{\"blobs_v2\": [ " << blobs << "],\"manifest\":\"" << manifest << "\""
+            l << "{\"blobs_v2\": [ " << blobs << R"(],"manifest":")" << manifest << "\""
               << ",\"refresh_interval\": " << interval << ",\"version\":" << (version + 1) << '}';
             return l.str();
         };
diff --git a/src/test/nodestore/Basics_test.cpp b/src/test/nodestore/Basics_test.cpp
index 5565399cc2..7d77b18630 100644
--- a/src/test/nodestore/Basics_test.cpp
+++ b/src/test/nodestore/Basics_test.cpp
@@ -40,9 +40,9 @@ public:
 
         auto batch = createPredictableBatch(kNumObjectsToTest, seedValue);
 
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& expected : batch)
         {
-            EncodedBlob const encoded(batch[i]);
+            EncodedBlob const encoded(expected);
 
             DecodedBlob decoded(encoded.getKey(), encoded.getData(), encoded.getSize());
 
@@ -52,7 +52,7 @@ public:
             {
                 std::shared_ptr<NodeObject> const object(decoded.createObject());
 
-                BEAST_EXPECT(isSame(batch[i], object));
+                BEAST_EXPECT(isSame(expected, object));
             }
         }
     }
diff --git a/src/test/nodestore/TestBase.h b/src/test/nodestore/TestBase.h
index 1254fc51aa..a1245ec963 100644
--- a/src/test/nodestore/TestBase.h
+++ b/src/test/nodestore/TestBase.h
@@ -124,9 +124,9 @@ public:
     static void
     storeBatch(Backend& backend, Batch const& batch)
     {
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& object : batch)
         {
-            backend.store(batch[i]);
+            backend.store(object);
         }
     }
 
@@ -137,11 +137,11 @@ public:
         pCopy->clear();
         pCopy->reserve(batch.size());
 
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& expected : batch)
         {
             std::shared_ptr<NodeObject> object;
 
-            Status const status = backend.fetch(batch[i]->getHash(), &object);
+            Status const status = backend.fetch(expected->getHash(), &object);
 
             BEAST_EXPECT(status == Status::Ok);
 
@@ -157,11 +157,11 @@ public:
     void
     fetchMissing(Backend& backend, Batch const& batch)
     {
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& expected : batch)
         {
             std::shared_ptr<NodeObject> object;
 
-            Status const status = backend.fetch(batch[i]->getHash(), &object);
+            Status const status = backend.fetch(expected->getHash(), &object);
 
             BEAST_EXPECT(status == Status::NotFound);
         }
@@ -171,10 +171,8 @@ public:
     static void
     storeBatch(Database& db, Batch const& batch)
     {
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& object : batch)
         {
-            std::shared_ptr<NodeObject> const object(batch[i]);
-
             Blob data(object->getData());
 
             db.store(object->getType(), std::move(data), object->getHash(), db.earliestLedgerSeq());
@@ -188,9 +186,9 @@ public:
         pCopy->clear();
         pCopy->reserve(batch.size());
 
-        for (int i = 0; i < batch.size(); ++i)
+        for (auto const& expected : batch)
         {
-            std::shared_ptr<NodeObject> const object = db.fetchNodeObject(batch[i]->getHash(), 0);
+            std::shared_ptr<NodeObject> const object = db.fetchNodeObject(expected->getHash(), 0);
 
             if (object != nullptr)
                 pCopy->push_back(object);
diff --git a/src/test/nodestore/Timing_test.cpp b/src/test/nodestore/Timing_test.cpp
index e308d0d5ff..1c296ca44c 100644
--- a/src/test/nodestore/Timing_test.cpp
+++ b/src/test/nodestore/Timing_test.cpp
@@ -564,10 +564,10 @@ public:
                     char p[2];
                     p[0] = rand_(gen_) < 50 ? 0 : 1;
                     p[1] = 1 - p[0];
-                    for (int q = 0; q < 2; ++q)
+                    for (char const op : p)
                     {
                         // NOLINTNEXTLINE(bugprone-switch-missing-default-case)
-                        switch (p[q])
+                        switch (op)
                         {
                             case 0: {
                                 // fetch recent
diff --git a/src/test/resource/Logic_test.cpp b/src/test/resource/Logic_test.cpp
index f6b4875356..40a81503f1 100644
--- a/src/test/resource/Logic_test.cpp
+++ b/src/test/resource/Logic_test.cpp
@@ -211,8 +211,8 @@ public:
 
         Gossip g[5];
 
-        for (int i = 0; i < 5; ++i)
-            createGossip(g[i]);
+        for (auto& gossip : g)
+            createGossip(gossip);
 
         for (int i = 0; i < 5; ++i)
             logic.importConsumers(std::to_string(i), g[i]);
diff --git a/src/test/rpc/AccountInfo_test.cpp b/src/test/rpc/AccountInfo_test.cpp
index d061be1f0e..61a11d0b93 100644
--- a/src/test/rpc/AccountInfo_test.cpp
+++ b/src/test/rpc/AccountInfo_test.cpp
@@ -234,7 +234,7 @@ public:
         withSigners[jss::account] = alice.human();
         withSigners[jss::signer_lists] = true;
 
-        auto const withSignersAsString = std::string("{ ") + "\"api_version\": 2, \"account\": \"" +
+        auto const withSignersAsString = std::string("{ ") + R"("api_version": 2, "account": ")" +
             alice.human() + "\", " + "\"signer_lists\": asdfggh }";
 
         // Alice has no SignerList yet.
diff --git a/src/test/rpc/GetAggregatePrice_test.cpp b/src/test/rpc/GetAggregatePrice_test.cpp
index 214bd12183..22c021865d 100644
--- a/src/test/rpc/GetAggregatePrice_test.cpp
+++ b/src/test/rpc/GetAggregatePrice_test.cpp
@@ -297,13 +297,13 @@ public:
 
             OraclesData oracles;
             prep(env, oracles);
-            for (int i = 0; i < oracles.size(); ++i)
+            for (auto& oracleData : oracles)
             {
                 Oracle oracle(
                     env,
-                    {.owner = oracles[i].first,
+                    {.owner = oracleData.first,
                      // NOLINTNEXTLINE(bugprone-unchecked-optional-access)
-                     .documentID = asUInt(*oracles[i].second),
+                     .documentID = asUInt(*oracleData.second),
                      .fee = baseFee},
                     false);
                 // push XRP/USD by two ledgers, so this price
diff --git a/src/test/rpc/JSONRPC_test.cpp b/src/test/rpc/JSONRPC_test.cpp
index 7f6b123533..e18974e7e7 100644
--- a/src/test/rpc/JSONRPC_test.cpp
+++ b/src/test/rpc/JSONRPC_test.cpp
@@ -2238,7 +2238,7 @@ public:
 
         {
             json::Value req;
-            json::Reader().parse("{ \"fee_mult_max\" : 1, \"tx_json\" : { } } ", req);
+            json::Reader().parse(R"({ "fee_mult_max" : 1, "tx_json" : { } } )", req);
             json::Value const result = checkFee(
                 req,
                 Role::ADMIN,
@@ -2275,7 +2275,7 @@ public:
 
         {
             json::Value req;
-            json::Reader().parse("{ \"fee_mult_max\" : 0, \"tx_json\" : { } } ", req);
+            json::Reader().parse(R"({ "fee_mult_max" : 0, "tx_json" : { } } )", req);
             json::Value const result = checkFee(
                 req,
                 Role::ADMIN,
diff --git a/src/test/rpc/LedgerEntry_test.cpp b/src/test/rpc/LedgerEntry_test.cpp
index 59dbf618f0..c7ef5cef2d 100644
--- a/src/test/rpc/LedgerEntry_test.cpp
+++ b/src/test/rpc/LedgerEntry_test.cpp
@@ -2917,29 +2917,32 @@ class LedgerEntry_XChain_test : public beast::unit_test::Suite,
             BEAST_EXPECT(
                 attest[json::Value::UInt(0)].isMember(sfXChainCreateAccountProofSig.jsonName));
             json::Value a[kNumAttest];
-            for (size_t i = 0; i < kNumAttest; ++i)
+            for (auto& attestation : a)
             {
-                a[i] = attest[json::Value::UInt(0)][sfXChainCreateAccountProofSig.jsonName];
+                attestation = attest[json::Value::UInt(0)][sfXChainCreateAccountProofSig.jsonName];
                 BEAST_EXPECT(
-                    a[i].isMember(jss::Amount) && a[i][jss::Amount].asInt() == 1000 * kDropPerXrp);
+                    attestation.isMember(jss::Amount) &&
+                    attestation[jss::Amount].asInt() == 1000 * kDropPerXrp);
                 BEAST_EXPECT(
-                    a[i].isMember(jss::Destination) && a[i][jss::Destination] == scCarol.human());
+                    attestation.isMember(jss::Destination) &&
+                    attestation[jss::Destination] == scCarol.human());
                 BEAST_EXPECT(
-                    a[i].isMember(sfAttestationSignerAccount.jsonName) &&
+                    attestation.isMember(sfAttestationSignerAccount.jsonName) &&
                     std::ranges::any_of(signers, [&](Signer const& s) {
-                        return a[i][sfAttestationSignerAccount.jsonName] == s.account.human();
+                        return attestation[sfAttestationSignerAccount.jsonName] ==
+                            s.account.human();
                     }));
                 BEAST_EXPECT(
-                    a[i].isMember(sfAttestationRewardAccount.jsonName) &&
+                    attestation.isMember(sfAttestationRewardAccount.jsonName) &&
                     std::ranges::any_of(payee, [&](Account const& account) {
-                        return a[i][sfAttestationRewardAccount.jsonName] == account.human();
+                        return attestation[sfAttestationRewardAccount.jsonName] == account.human();
                     }));
                 BEAST_EXPECT(
-                    a[i].isMember(sfWasLockingChainSend.jsonName) &&
-                    a[i][sfWasLockingChainSend.jsonName] == 1);
+                    attestation.isMember(sfWasLockingChainSend.jsonName) &&
+                    attestation[sfWasLockingChainSend.jsonName] == 1);
                 BEAST_EXPECT(
-                    a[i].isMember(sfSignatureReward.jsonName) &&
-                    a[i][sfSignatureReward.jsonName].asInt() == 1 * kDropPerXrp);
+                    attestation.isMember(sfSignatureReward.jsonName) &&
+                    attestation[sfSignatureReward.jsonName].asInt() == 1 * kDropPerXrp);
             }
         }
 
diff --git a/src/test/rpc/ServerDefinitions_test.cpp b/src/test/rpc/ServerDefinitions_test.cpp
index bac1b4f7a5..bf345e6fdf 100644
--- a/src/test/rpc/ServerDefinitions_test.cpp
+++ b/src/test/rpc/ServerDefinitions_test.cpp
@@ -433,7 +433,7 @@ public:
                 Env env(*this);
                 auto const firstResult = env.rpc("server_definitions");
                 auto const hash = firstResult[jss::result][jss::hash].asString();
-                auto const hashParam = std::string("{ ") + "\"hash\": \"" + hash + "\"}";
+                auto const hashParam = std::string("{ ") + R"("hash": ")" + hash + "\"}";
 
                 auto const result = env.rpc("json", "server_definitions", hashParam);
                 BEAST_EXPECT(!result[jss::result].isMember(jss::error));
@@ -456,7 +456,7 @@ public:
                 std::string const hash =
                     "54296160385A27154BFA70A239DD8E8FD4CC2DB7BA32D970BA3A5B132CF749"
                     "D1";
-                auto const hashParam = std::string("{ ") + "\"hash\": \"" + hash + "\"}";
+                auto const hashParam = std::string("{ ") + R"("hash": ")" + hash + "\"}";
 
                 auto const result = env.rpc("json", "server_definitions", hashParam);
                 BEAST_EXPECT(!result[jss::result].isMember(jss::error));
diff --git a/src/test/rpc/Version_test.cpp b/src/test/rpc/Version_test.cpp
index 20740bfe53..71830c2219 100644
--- a/src/test/rpc/Version_test.cpp
+++ b/src/test/rpc/Version_test.cpp
@@ -76,7 +76,7 @@ class Version_test : public beast::unit_test::Suite
                 "}");
         BEAST_EXPECT(badVersion(re));
 
-        re = env.rpc("json", "version", "{\"api_version\": \"a\"}");
+        re = env.rpc("json", "version", R"({"api_version": "a"})");
         BEAST_EXPECT(badVersion(re));
     }
 
diff --git a/src/test/shamap/SHAMapSync_test.cpp b/src/test/shamap/SHAMapSync_test.cpp
index 9e9a490977..bb05ec56df 100644
--- a/src/test/shamap/SHAMapSync_test.cpp
+++ b/src/test/shamap/SHAMapSync_test.cpp
@@ -18,7 +18,6 @@
 #include <boost/smart_ptr/intrusive_ptr.hpp>
 
 #include <chrono>
-#include <cstddef>
 #include <cstdint>
 #include <list>
 #include <ostream>
@@ -154,12 +153,12 @@ public:
             if (b.empty())
                 fail("", __FILE__, __LINE__);
 
-            for (std::size_t i = 0; i < b.size(); ++i)
+            for (auto& node : b)
             {
                 // Don't use BEAST_EXPECT here b/c it will be called a
                 // non-deterministic number of times and the number of tests run
                 // should be deterministic
-                if (!destination.addKnownNode(b[i].first, makeSlice(b[i].second), nullptr)
+                if (!destination.addKnownNode(node.first, makeSlice(node.second), nullptr)
                          .isUseful())
                     fail("", __FILE__, __LINE__);
             }
diff --git a/src/tests/libxrpl/json/Value.cpp b/src/tests/libxrpl/json/Value.cpp
index 03f565dffb..a1cd8160d7 100644
--- a/src/tests/libxrpl/json/Value.cpp
+++ b/src/tests/libxrpl/json/Value.cpp
@@ -838,7 +838,7 @@ TEST(json_value, compact)
 {
     json::Value j;
     json::Reader r;
-    char const* s("{\"array\":[{\"12\":23},{},null,false,0.5]}");
+    char const* s(R"({"array":[{"12":23},{},null,false,0.5]})");
 
     auto countLines = [](std::string const& str) {
         return 1 + std::count_if(str.begin(), str.end(), [](char c) { return c == '\n'; });
diff --git a/src/xrpld/app/ledger/TransactionMaster.h b/src/xrpld/app/ledger/TransactionMaster.h
index 5dcad09f51..6d81911510 100644
--- a/src/xrpld/app/ledger/TransactionMaster.h
+++ b/src/xrpld/app/ledger/TransactionMaster.h
@@ -68,7 +68,7 @@ public:
     canonicalize(std::shared_ptr<Transaction>* pTransaction);
 
     void
-    sweep(void);
+    sweep();
 
     TaggedCache<uint256, Transaction>&
     getCache();
diff --git a/src/xrpld/app/ledger/detail/TransactionMaster.cpp b/src/xrpld/app/ledger/detail/TransactionMaster.cpp
index 129681b906..ac2aa1aabe 100644
--- a/src/xrpld/app/ledger/detail/TransactionMaster.cpp
+++ b/src/xrpld/app/ledger/detail/TransactionMaster.cpp
@@ -152,7 +152,7 @@ TransactionMaster::canonicalize(std::shared_ptr<Transaction>* pTransaction)
 }
 
 void
-TransactionMaster::sweep(void)
+TransactionMaster::sweep()
 {
     cache_.sweep();
 }
diff --git a/src/xrpld/app/rdb/detail/PeerFinder.cpp b/src/xrpld/app/rdb/detail/PeerFinder.cpp
index c40e3e42c6..abdcd1c61a 100644
--- a/src/xrpld/app/rdb/detail/PeerFinder.cpp
+++ b/src/xrpld/app/rdb/detail/PeerFinder.cpp
@@ -147,10 +147,10 @@ updatePeerFinderDB(soci::session& session, int currentSchemaVersion, beast::Jour
             s.reserve(list.size());
             valence.reserve(list.size());
 
-            for (auto iter(list.cbegin()); iter != list.cend(); ++iter)
+            for (auto const& entry : list)
             {
-                s.emplace_back(to_string(iter->endpoint));
-                valence.emplace_back(iter->valence);
+                s.emplace_back(to_string(entry.endpoint));
+                valence.emplace_back(entry.valence);
             }
 
             session << "INSERT INTO PeerFinder_BootstrapCache_Next ( "
diff --git a/src/xrpld/core/detail/Config.cpp b/src/xrpld/core/detail/Config.cpp
index 07c780118a..0706163ab1 100644
--- a/src/xrpld/core/detail/Config.cpp
+++ b/src/xrpld/core/detail/Config.cpp
@@ -98,7 +98,7 @@ getMemorySize()
     std::int64_t ram = 0;
     size_t size = sizeof(ram);
 
-    if (sysctl(mib, 2, &ram, &size, NULL, 0) == 0)
+    if (sysctl(mib, 2, &ram, &size, nullptr, 0) == 0)
         return static_cast<std::uint64_t>(ram);
 
     return 0;
@@ -917,7 +917,7 @@ Config::loadFromString(std::string const& fileContents)
     if (getSingleSection(secConfig, Sections::kAmendmentMajorityTime, strTemp, j_))
     {
         using namespace std::chrono;
-        boost::regex const re("^\\s*(\\d+)\\s*(minutes|hours|days|weeks)\\s*(\\s+.*)?$");
+        boost::regex const re(R"(^\s*(\d+)\s*(minutes|hours|days|weeks)\s*(\s+.*)?$)");
         boost::smatch match;
         if (!boost::regex_match(strTemp, match, re))
         {
diff --git a/src/xrpld/peerfinder/detail/Bootcache.h b/src/xrpld/peerfinder/detail/Bootcache.h
index 5384bb356a..cee03fa322 100644
--- a/src/xrpld/peerfinder/detail/Bootcache.h
+++ b/src/xrpld/peerfinder/detail/Bootcache.h
@@ -3,7 +3,6 @@
 #include <xrpld/peerfinder/PeerfinderManager.h>
 #include <xrpld/peerfinder/detail/Store.h>
 
-#include <xrpl/basics/comparators.h>
 #include <xrpl/beast/net/IPEndpoint.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/beast/utility/PropertyStream.h>
@@ -13,6 +12,8 @@
 #include <boost/bimap/unordered_set_of.hpp>
 #include <boost/iterator/transform_iterator.hpp>
 
+#include <functional>
+
 namespace xrpl::PeerFinder {
 
 /** Stores IP addresses useful for gaining initial connections.
@@ -62,11 +63,9 @@ private:
         int valence_;
     };
 
-    using left_t = boost::bimaps::unordered_set_of<
-        beast::IP::Endpoint,
-        boost::hash<beast::IP::Endpoint>,
-        xrpl::equal_to<beast::IP::Endpoint>>;
-    using right_t = boost::bimaps::multiset_of<Entry, xrpl::less<Entry>>;
+    using left_t = boost::bimaps::
+        unordered_set_of<beast::IP::Endpoint, boost::hash<beast::IP::Endpoint>, std::equal_to<>>;
+    using right_t = boost::bimaps::multiset_of<Entry, std::less<>>;
     using map_type = boost::bimap<left_t, right_t>;
     using value_type = map_type::value_type;
 
diff --git a/src/xrpld/peerfinder/detail/SourceStrings.cpp b/src/xrpld/peerfinder/detail/SourceStrings.cpp
index 61a3e0c021..7b28db4306 100644
--- a/src/xrpld/peerfinder/detail/SourceStrings.cpp
+++ b/src/xrpld/peerfinder/detail/SourceStrings.cpp
@@ -32,11 +32,11 @@ public:
     {
         results.addresses.resize(0);
         results.addresses.reserve(strings_.size());
-        for (int i = 0; i < strings_.size(); ++i)
+        for (auto const& str : strings_)
         {
-            beast::IP::Endpoint ep(beast::IP::Endpoint::fromString(strings_[i]));
+            beast::IP::Endpoint ep(beast::IP::Endpoint::fromString(str));
             if (isUnspecified(ep))
-                ep = beast::IP::Endpoint::fromString(strings_[i]);
+                ep = beast::IP::Endpoint::fromString(str);
             if (!isUnspecified(ep))
                 results.addresses.push_back(ep);
         }
diff --git a/src/xrpld/rpc/handlers/account/GatewayBalances.cpp b/src/xrpld/rpc/handlers/account/GatewayBalances.cpp
index bd1681172c..a6730c8e2b 100644
--- a/src/xrpld/rpc/handlers/account/GatewayBalances.cpp
+++ b/src/xrpld/rpc/handlers/account/GatewayBalances.cpp
@@ -106,8 +106,8 @@ doGatewayBalances(RPC::JsonContext& context)
         // null is treated as a valid 0-sized array of hotwallet
         if (hw.isArrayOrNull())
         {
-            for (unsigned i = 0; i < hw.size(); ++i)
-                valid &= addHotWallet(hw[i]);
+            for (auto const& wallet : hw)
+                valid &= addHotWallet(wallet);
         }
         else if (hw.isString())
         {
diff --git a/src/xrpld/rpc/handlers/orderbook/GetAggregatePrice.cpp b/src/xrpld/rpc/handlers/orderbook/GetAggregatePrice.cpp
index c1c8712655..d2f596ed8e 100644
--- a/src/xrpld/rpc/handlers/orderbook/GetAggregatePrice.cpp
+++ b/src/xrpld/rpc/handlers/orderbook/GetAggregatePrice.cpp
@@ -40,8 +40,7 @@ namespace xrpl {
 
 using namespace boost::bimaps;
 // sorted descending by lastUpdateTime, ascending by AssetPrice
-using Prices =
-    bimap<multiset_of<std::uint32_t, std::greater<std::uint32_t>>, multiset_of<STAmount>>;
+using Prices = bimap<multiset_of<std::uint32_t, std::greater<>>, multiset_of<STAmount>>;
 
 /** Calls callback "f" on the ledger-object sle and up to three previous
  * metadata objects. Stops early if the callback returns true.