Squashed 'deps/oxlib/' content from commit 85f17c41

git-subtree-dir: deps/oxlib
git-subtree-split: 85f17c4188e266b82ba8858d21f67289c72e7b9a

src/CMakeLists.txt

@@ -0,0 +1,27 @@
+if(${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
+	set(OX_OS_WINDOWS TRUE)
+endif()
+if(${CMAKE_SYSTEM_NAME} STREQUAL "FreeBSD")
+	set(OX_OS_FREEBSD TRUE)
+else()
+	set(OX_OS_FREEBSD FALSE)
+endif()
+
+if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
+	set(OX_OS_LINUX TRUE)
+else()
+	set(OX_OS_LINUX FALSE)
+endif()
+
+if(OX_USE_STDLIB)
+	add_subdirectory(oc)
+endif()
+add_subdirectory(clargs)
+add_subdirectory(claw)
+add_subdirectory(event)
+add_subdirectory(fs)
+add_subdirectory(logconn)
+add_subdirectory(mc)
+add_subdirectory(model)
+add_subdirectory(preloader)
+add_subdirectory(std)

src/clargs/CMakeLists.txt

@@ -0,0 +1,47 @@
+
+if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+	# enable warnings
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wunsafe-buffer-usage")
+endif()
+
+
+add_library(
+	OxClArgs
+		src/clargs.cpp
+)
+
+set_property(
+	TARGET
+		OxClArgs
+	PROPERTY
+		POSITION_INDEPENDENT_CODE ON
+)
+
+if(NOT MSVC)
+	target_compile_options(OxClArgs PRIVATE -Wsign-conversion)
+	target_compile_options(OxClArgs PRIVATE -Wconversion)
+endif()
+
+target_link_libraries(
+	OxClArgs PUBLIC
+		OxStd
+)
+
+target_include_directories(
+	OxClArgs PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS
+		OxClArgs
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)

src/clargs/include/ox/clargs/clargs.hpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/hashmap.hpp>
+#include <ox/std/span.hpp>
+#include <ox/std/string.hpp>
+
+namespace ox {
+
+class ClArgs {
+	private:
+		HashMap<String, bool> m_bools;
+		HashMap<String, String> m_strings;
+		HashMap<String, int> m_ints;
+
+	public:
+		ClArgs(int argc, const char **args) noexcept;
+
+		ClArgs(ox::SpanView<const char*> args) noexcept;
+
+		[[nodiscard]]
+		bool getBool(ox::StringViewCR arg, bool defaultValue) const noexcept;
+
+		[[nodiscard]]
+		String getString(ox::StringViewCR argName, ox::StringView defaultValue) const noexcept;
+
+		[[nodiscard]]
+		int getInt(ox::StringViewCR arg, int defaultValue) const noexcept;
+
+		[[nodiscard]]
+		Result<bool> getBool(ox::StringViewCR arg) const noexcept;
+
+		[[nodiscard]]
+		Result<String> getString(ox::StringViewCR argName) const noexcept;
+
+		Result<int> getInt(ox::StringViewCR arg) const noexcept;
+
+};
+
+}

src/clargs/src/clargs.cpp

@@ -0,0 +1,72 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/string.hpp>
+#include <ox/clargs/clargs.hpp>
+
+namespace ox {
+
+ClArgs::ClArgs(int argc, const char **args) noexcept: ClArgs({args, static_cast<size_t>(argc)}) {}
+
+ClArgs::ClArgs(ox::SpanView<const char*> args) noexcept {
+	for (auto i = 0u; i < args.size(); ++i) {
+		auto arg = StringView{args[i]};
+		if (arg[0] == '-') {
+			while (arg[0] == '-' && arg.size()) {
+				arg = substr(arg, 1);
+			}
+			m_bools[arg] = true;
+			// parse additional arguments
+			if (i < args.size() && args[i + 1]) {
+				auto const val = StringView{args[i + 1]};
+				if (val.size() && val[0] != '-') {
+					if (val == "false") {
+						m_bools[arg] = false;
+					}
+					m_strings[arg] = val;
+					if (auto r = ox::strToInt(val); r.error == 0) {
+						m_ints[arg] = r.value;
+					}
+					++i;
+				}
+			}
+		}
+	}
+}
+
+bool ClArgs::getBool(ox::StringViewCR arg, bool defaultValue) const noexcept {
+	auto const [value, err] = m_ints.at(arg);
+	return !err ? *value : defaultValue;
+}
+
+String ClArgs::getString(ox::StringViewCR arg, ox::StringView defaultValue) const noexcept {
+	auto const [value, err] = m_strings.at(arg);
+	return !err ? ox::String(*value) : ox::String(defaultValue);
+}
+
+int ClArgs::getInt(ox::StringViewCR arg, int defaultValue) const noexcept {
+	auto const [value, err] = m_ints.at(arg);
+	return !err ? *value : defaultValue;
+}
+
+Result<bool> ClArgs::getBool(ox::StringViewCR arg) const noexcept {
+	OX_REQUIRE(out, m_bools.at(arg));
+	return *out;
+}
+
+Result<String> ClArgs::getString(ox::StringViewCR argName) const noexcept {
+	OX_REQUIRE(out, m_strings.at(argName));
+	return *out;
+}
+
+Result<int> ClArgs::getInt(ox::StringViewCR arg) const noexcept {
+	OX_REQUIRE(out, m_ints.at(arg));
+	return *out;
+}
+
+}

src/claw/CMakeLists.txt

@@ -0,0 +1,50 @@
+
+add_library(
+	OxClaw
+		src/read.cpp
+		src/write.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxClaw PRIVATE -Wsign-conversion)
+	target_compile_options(OxClaw PRIVATE -Wconversion)
+endif()
+
+target_link_libraries(
+	OxClaw PUBLIC
+		OxMetalClaw
+		$<$<BOOL:${OX_USE_STDLIB}>:OxOrganicClaw>
+)
+
+#if(OX_USE_STDLIB)
+#	add_executable(
+#		readclaw
+#			readclaw.cpp
+#	)
+#	target_link_libraries(
+#		readclaw PUBLIC
+#			OxClaw
+#	)
+#endif()
+
+target_include_directories(
+	OxClaw PUBLIC
+		include
+)
+
+install(
+    DIRECTORY
+        include/ox
+    DESTINATION
+        include
+)
+
+install(
+	TARGETS OxClaw
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/claw/include/ox/claw/claw.hpp

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "read.hpp"
+#include "write.hpp"

src/claw/include/ox/claw/format.hpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+namespace ox {
+
+enum class ClawFormat {
+	None,
+	Metal,
+	Organic,
+};
+
+}

src/claw/include/ox/claw/read.hpp

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/span.hpp>
+#include <ox/mc/read.hpp>
+#ifdef OX_USE_STDLIB
+#include <ox/oc/read.hpp>
+#endif
+#include <ox/std/buffer.hpp>
+#include <ox/std/string.hpp>
+
+#include "format.hpp"
+
+namespace ox {
+
+constexpr auto Error_ClawTypeMismatch = 200;
+constexpr auto Error_ClawTypeVersionMismatch = 201;
+
+struct ClawHeader {
+	String typeName;
+	int typeVersion = -1;
+	TypeParamPack typeParams;
+	ClawFormat fmt = ClawFormat::None;
+	const char *data = nullptr;
+	std::size_t dataSize = 0;
+};
+
+ox::Result<ox::StringView> readClawTypeId(ox::BufferView buff) noexcept;
+
+Result<ClawHeader> readClawHeader(ox::BufferView buff) noexcept;
+
+Result<BufferView> stripClawHeader(ox::BufferView buff) noexcept;
+
+template<typename T>
+Error readClaw(ox::BufferView buff, T &val) {
+	OX_REQUIRE(header, readClawHeader(buff));
+	if (header.typeName != getModelTypeName<T>()) {
+		return ox::Error(Error_ClawTypeMismatch, "Claw Read: Type mismatch");
+	}
+	if (header.typeVersion != getModelTypeVersion<T>()) {
+		return ox::Error(Error_ClawTypeVersionMismatch, "Claw Read: Type Version mismatch");
+	}
+	switch (header.fmt) {
+		case ClawFormat::Metal:
+		{
+			ox::BufferReader br({header.data, header.dataSize});
+			MetalClawReader reader(br);
+			return model(reader.interface(), &val);
+		}
+		case ClawFormat::Organic:
+		{
+#ifdef OX_USE_STDLIB
+			OrganicClawReader reader(header.data, header.dataSize);
+			return model(&reader, &val);
+#else
+			break;
+#endif
+		}
+		case ClawFormat::None:
+			return ox::Error(1);
+	}
+	return ox::Error(1);
+}
+
+template<typename T>
+Result<T> readClaw(ox::BufferView buff) {
+	Result<T> val;
+	OX_RETURN_ERROR(readClaw(buff, val.value));
+	return val;
+}
+
+Result<ModelObject> readClaw(TypeStore &ts, BufferView buff) noexcept;
+
+}

src/claw/include/ox/claw/write.hpp

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/mc/write.hpp>
+#ifdef OX_USE_STDLIB
+#include <ox/oc/write.hpp>
+#endif
+#include <ox/std/buffer.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/stringview.hpp>
+
+#include "format.hpp"
+
+namespace ox {
+
+namespace detail {
+
+struct TypeInfoCatcher {
+
+	const char *name = nullptr;
+	int version = 0;
+
+	template<typename T>
+	constexpr ox::Error setTypeInfo(
+			const char *pName = T::TypeName,
+			int pVersion = T::TypeVersion,
+			const Vector<String>& = {},
+			std::size_t = 0) noexcept {
+		this->name = pName;
+		this->version = pVersion;
+		return {};
+	}
+
+	constexpr Error field(...) noexcept {
+		return {};
+	}
+
+	static constexpr auto opType() {
+		return OpType::Write;
+	}
+
+};
+
+template<typename T, typename = int>
+struct type_version {
+	static constexpr auto value = -1;
+};
+
+template<typename T>
+struct type_version<T, decltype((void) T::TypeVersion, -1)> {
+	static constexpr auto value = T::TypeVersion;
+};
+
+template<typename T>
+constexpr const char *getTypeName(const T *t) noexcept {
+	TypeInfoCatcher tnc;
+	std::ignore = model(&tnc, t);
+	return tnc.name;
+}
+
+template<typename T>
+constexpr int getTypeVersion(const T *t) noexcept {
+	TypeInfoCatcher tnc;
+	std::ignore = model(&tnc, t);
+	return tnc.version;
+}
+
+template<typename T>
+ox::Error writeClawHeader(Writer_c auto &writer, const T *t, ClawFormat fmt) noexcept {
+	switch (fmt) {
+		case ClawFormat::Metal:
+			OX_RETURN_ERROR(write(writer, "M2;"));
+			break;
+		case ClawFormat::Organic:
+			OX_RETURN_ERROR(write(writer, "O1;"));
+			break;
+		default:
+			return ox::Error(1);
+	}
+	OX_RETURN_ERROR(write(writer, detail::getTypeName(t)));
+	OX_RETURN_ERROR(writer.put(';'));
+	const auto tn = detail::getTypeVersion(t);
+	if (tn > -1) {
+		OX_RETURN_ERROR(ox::writeItoa(tn, writer));
+	}
+	OX_RETURN_ERROR(writer.put(';'));
+	return {};
+}
+
+}
+
+Result<Buffer> writeClaw(
+		const auto &t,
+		ClawFormat fmt = ClawFormat::Metal,
+		std::size_t buffReserveSz = 2 * units::KB) noexcept {
+	Buffer out(buffReserveSz);
+	BufferWriter bw(&out, 0);
+	OX_RETURN_ERROR(detail::writeClawHeader(bw, &t, fmt));
+#ifdef OX_USE_STDLIB
+	if (fmt == ClawFormat::Metal) {
+		OX_RETURN_ERROR(writeMC(bw, t));
+	} else if (fmt == ClawFormat::Organic) {
+		OX_REQUIRE(data, writeOC(t));
+		OX_RETURN_ERROR(bw.write(data.data(), data.size()));
+	}
+#else
+	if (fmt != ClawFormat::Metal) {
+		return ox::Error(1, "OC is not supported in this build");
+	}
+	OX_RETURN_ERROR(writeMC(bw, t));
+#endif
+	out.resize(bw.tellp());
+	return out;
+}
+
+}

src/claw/src/read.cpp

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/buffer.hpp>
+
+#include <ox/claw/read.hpp>
+
+namespace ox {
+
+Result<StringView> readClawTypeId(BufferView const buff) noexcept {
+	auto buffRaw = buff.data();
+	auto buffLen = buff.size();
+	size_t outSz{};
+	const auto s1End = ox::strchr(buffRaw, ';', buffLen);
+	if (!s1End) {
+		return ox::Error(1, "Could not read Claw header");
+	}
+	auto const fmtSz = static_cast<std::size_t>(s1End - buffRaw) + 1;
+	buffRaw += fmtSz;
+	buffLen -= fmtSz;
+	outSz += fmtSz;
+	auto const s2End = ox::strchr(buffRaw, ';', buffLen);
+	if (!s2End) {
+		return ox::Error(2, "Could not read Claw header");
+	}
+	auto const s2Size = static_cast<std::size_t>(s2End - buffRaw) + 1;
+	buffRaw += s2Size;
+	buffLen -= s2Size;
+	outSz += s2Size;
+	auto const s3End = ox::strchr(buffRaw, ';', buffLen) + 1;
+	if (!s3End) {
+		return ox::Error(3, "Could not read Claw header");
+	}
+	auto const s3Size = static_cast<std::size_t>(s3End - buffRaw);
+	buffRaw += s3Size;
+	buffLen -= s3Size;
+	outSz += s3Size;
+	return {{buff.data() + fmtSz, outSz - fmtSz - 1}};
+}
+
+Result<ClawHeader> readClawHeader(BufferView const buff) noexcept {
+	auto buffRaw = buff.data();
+	auto buffLen = buff.size();
+	const auto s1End = ox::strchr(buffRaw, ';', buffLen);
+	if (!s1End) {
+		return ox::Error(1, "Could not read Claw header");
+	}
+	auto const s1Size = static_cast<std::size_t>(s1End - buffRaw);
+	StringView const fmt(buffRaw, s1Size);
+	buffRaw += s1Size + 1;
+	buffLen -= s1Size + 1;
+
+	auto const s2End = ox::strchr(buffRaw, ';', buffLen);
+	if (!s2End) {
+		return ox::Error(2, "Could not read Claw header");
+	}
+	auto const s2Size = static_cast<std::size_t>(s2End - buffRaw);
+	StringView const typeName(buffRaw, s2Size);
+	buffRaw += s2Size + 1;
+	buffLen -= s2Size + 1;
+
+	auto const s3End = ox::strchr(buffRaw, ';', buffLen);
+	if (!s3End) {
+		return ox::Error(3, "Could not read Claw header");
+	}
+	auto const s3Size = static_cast<std::size_t>(s3End - buffRaw);
+	StringView const versionStr(buffRaw, s3Size);
+	buffRaw += s3Size + 1;
+	buffLen -= s3Size + 1;
+	ClawHeader hdr;
+	if (fmt == "M2") {
+		hdr.fmt = ClawFormat::Metal;
+	} else if (fmt == "O1") {
+		hdr.fmt = ClawFormat::Organic;
+	} else {
+		return ox::Error(4, "Claw format does not match any supported format/version combo");
+	}
+	hdr.typeName = typeName;
+	std::ignore = ox::strToInt(versionStr).copyTo(hdr.typeVersion);
+	hdr.data = buffRaw;
+	hdr.dataSize = buffLen;
+	return hdr;
+}
+
+Result<BufferView> stripClawHeader(BufferView const buff) noexcept {
+	OX_REQUIRE(header, readClawHeader(buff));
+	return {{header.data, header.dataSize}};
+}
+
+Result<ModelObject> readClaw(TypeStore &ts, BufferView buff) noexcept {
+	OX_REQUIRE(header, readClawHeader(buff));
+	auto const [t, tdErr] = ts.getLoad(
+			header.typeName, header.typeVersion, header.typeParams);
+	if (tdErr) {
+		return ox::Error(3, "Could not load type descriptor");
+	}
+	ModelObject obj;
+	OX_RETURN_ERROR(obj.setType(t));
+	switch (header.fmt) {
+		case ClawFormat::Metal:
+		{
+			ox::BufferReader br({header.data, header.dataSize});
+			MetalClawReader reader(br);
+			OX_RETURN_ERROR(model(reader.interface(), &obj));
+			return obj;
+		}
+		case ClawFormat::Organic:
+		{
+#ifdef OX_USE_STDLIB
+			OrganicClawReader reader({header.data, header.dataSize});
+			ModelHandlerInterface handler(reader);
+			OX_RETURN_ERROR(model(&handler, &obj));
+			return obj;
+#else
+			break;
+#endif
+		}
+		case ClawFormat::None:
+			return ox::Error(1);
+	}
+	return ox::Error(1);
+}
+
+}

src/claw/src/readclaw.cpp

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <cstdio>
+
+#include <ox/std/reader.hpp>
+#include <ox/std/trace.hpp>
+
+#include "claw.hpp"
+
+
+int main(int argc, char **args) {
+	if (argc > 2) {
+		oxErr("Too many arguments");
+		return -1;
+	}
+	auto const file = argc == 1 ? stdin : fopen(args[1], "r");
+	if (fseek(file, 0, SEEK_END)) {
+		oxErr("Could not get file size\n");
+		return -2;
+	}
+	auto const size = static_cast<std::size_t>(ftell(file));
+	oxDebugf("{}", size);
+	return 0;
+}

src/claw/src/write.cpp

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/claw/write.hpp>
+
+namespace ox::detail {
+
+struct versioned_type {
+	static constexpr int TypeVersion = 4;
+};
+
+struct unversioned_type {
+};
+
+static_assert(type_version<versioned_type>::value == 4);
+static_assert(type_version<unversioned_type>::value == -1);
+
+}

src/claw/test/CMakeLists.txt

@@ -0,0 +1,15 @@
+add_executable(
+	ClawTest
+		tests.cpp
+)
+
+target_link_libraries(
+	ClawTest
+		OxClaw
+)
+
+add_test("[ox/claw] ClawHeaderReader" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ClawTest ClawHeaderReader)
+add_test("[ox/claw] ClawHeaderReader2" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ClawTest ClawHeaderReader2)
+add_test("[ox/claw] ClawHeaderReadTypeId" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ClawTest ClawHeaderReadTypeId)
+add_test("[ox/claw] ClawWriter" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ClawTest ClawWriter)
+add_test("[ox/claw] ClawReader" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ClawTest ClawReader)

src/claw/test/tests.cpp

@@ -0,0 +1,211 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#undef NDEBUG
+
+#include <map>
+#include <ox/claw/format.hpp>
+#include <ox/claw/read.hpp>
+#include <ox/claw/write.hpp>
+#include <ox/mc/mc.hpp>
+#include <ox/model/model.hpp>
+#include <ox/std/std.hpp>
+
+union TestUnion {
+	static constexpr auto TypeName = "TestUnion";
+	static constexpr auto TypeVersion = 1;
+	bool Bool;
+	uint32_t Int = 5;
+	char *String;
+};
+
+struct TestStructNest {
+	static constexpr auto TypeName = "TestStructNest";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	uint32_t Int = 0;
+	ox::IString<32> String = "";
+};
+
+struct TestStruct {
+	static constexpr auto TypeName = "TestStruct";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	int32_t Int = 0;
+	int32_t Int1 = 0;
+	int32_t Int2 = 0;
+	int32_t Int3 = 0;
+	int32_t Int4 = 0;
+	int32_t Int5 = 0;
+	int32_t Int6 = 0;
+	int32_t Int7 = 0;
+	int32_t Int8 = 0;
+	int unionIdx = 1;
+	TestUnion Union;
+	ox::IString<32> String = "";
+	uint32_t List[4] = {0, 0, 0, 0};
+	TestStructNest EmptyStruct;
+	TestStructNest Struct;
+
+	~TestStruct() {
+		if (unionIdx == 2) {
+			ox::safeDelete(Union.String);
+		}
+	}
+
+};
+
+template<typename T>
+constexpr ox::Error model(T *io, ox::CommonPtrWith<TestUnion> auto *obj) {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestUnion>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->fieldCString("String", &obj->String));
+	return ox::Error(0);
+}
+
+template<typename T>
+constexpr ox::Error model(T *io, ox::CommonPtrWith<TestStructNest> auto *obj) {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestStructNest>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->field("String", &obj->String));
+	return ox::Error(0);
+}
+
+template<typename T>
+constexpr ox::Error model(T *io, ox::CommonPtrWith<TestStruct> auto *obj) {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestStruct>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->field("Int1", &obj->Int1));
+	OX_RETURN_ERROR(io->field("Int2", &obj->Int2));
+	OX_RETURN_ERROR(io->field("Int3", &obj->Int3));
+	OX_RETURN_ERROR(io->field("Int4", &obj->Int4));
+	OX_RETURN_ERROR(io->field("Int5", &obj->Int5));
+	OX_RETURN_ERROR(io->field("Int6", &obj->Int6));
+	OX_RETURN_ERROR(io->field("Int7", &obj->Int7));
+	OX_RETURN_ERROR(io->field("Int8", &obj->Int8));
+	int unionIdx = 0;
+	if constexpr(T::opType() != ox::OpType::Reflect) {
+		unionIdx = obj->unionIdx;
+	}
+	OX_RETURN_ERROR(io->field("Union", ox::UnionView{&obj->Union, unionIdx}));
+	OX_RETURN_ERROR(io->field("String", &obj->String));
+	OX_RETURN_ERROR(io->field("List", obj->List, 4));
+	OX_RETURN_ERROR(io->field("EmptyStruct", &obj->EmptyStruct));
+	OX_RETURN_ERROR(io->field("Struct", &obj->Struct));
+	return ox::Error(0);
+}
+
+static std::map<ox::StringView, ox::Error(*)()> tests = {
+	{
+		{
+			"ClawHeaderReader",
+			[] {
+				constexpr auto hdr = ox::StringLiteral("O1;com.drinkingtea.ox.claw.test.Header;2;");
+				auto [ch, err] = ox::readClawHeader({hdr.c_str(), hdr.size() + 1});
+				oxAssert(err, "Error parsing header");
+				oxAssert(ch.fmt == ox::ClawFormat::Organic, "Format wrong");
+				oxAssert(ch.typeName == "com.drinkingtea.ox.claw.test.Header", "Type name wrong");
+				oxAssert(ch.typeVersion == 2, "Type version wrong");
+				return ox::Error(0);
+			}
+		},
+		{
+			"ClawHeaderReader2",
+			[] {
+				constexpr auto hdr = ox::StringLiteral("M2;com.drinkingtea.ox.claw.test.Header2;3;");
+				auto [ch, err] = ox::readClawHeader({hdr.c_str(), hdr.size() + 1});
+				oxAssert(err, "Error parsing header");
+				oxAssert(ch.fmt == ox::ClawFormat::Metal, "Format wrong");
+				oxAssert(ch.typeName == "com.drinkingtea.ox.claw.test.Header2", "Type name wrong");
+				oxAssert(ch.typeVersion == 3, "Type version wrong");
+				return ox::Error(0);
+			}
+		},
+		{
+			"ClawHeaderReadTypeId",
+			[] {
+				constexpr auto hdr = ox::StringLiteral("M2;com.drinkingtea.ox.claw.test.Header2;3;awefawf");
+				constexpr auto expected = ox::StringLiteral("com.drinkingtea.ox.claw.test.Header2;3");
+				OX_REQUIRE(actual, ox::readClawTypeId({hdr.data(), hdr.size() + 1}));
+				ox::expect(actual, expected);
+				return ox::Error{};
+			}
+		},
+		{
+			"ClawWriter",
+			[] {
+				// This test doesn't confirm much, but it does show that the writer
+				// doesn't segfault
+				TestStruct ts;
+				OX_RETURN_ERROR(ox::writeClaw(ts, ox::ClawFormat::Metal));
+				return ox::Error(0);
+			}
+		},
+		{
+			"ClawReader",
+			[] {
+				TestStruct testIn, testOut;
+				testIn.Bool = true;
+				testIn.Int = 42;
+				testIn.Union.Int = 42;
+				testIn.String = "Test String 1";
+				testIn.List[0] = 1;
+				testIn.List[1] = 2;
+				testIn.List[2] = 3;
+				testIn.List[3] = 4;
+				testIn.Struct.Bool = false;
+				testIn.Struct.Int = 300;
+				testIn.Struct.String = "Test String 2";
+				const auto [buff, err] = ox::writeMC(testIn);
+				oxAssert(err, "writeClaw failed");
+				oxAssert(ox::readMC(buff, testOut), "readClaw failed");
+				//std::cout << testIn.Union.Int << "|" << testOut.Union.Int << "|\n";
+				oxAssert(testIn.Bool               == testOut.Bool, "Bool value mismatch");
+				oxAssert(testIn.Int                == testOut.Int, "Int value mismatch");
+				oxAssert(testIn.Int1               == testOut.Int1, "Int1 value mismatch");
+				oxAssert(testIn.Int2               == testOut.Int2, "Int2 value mismatch");
+				oxAssert(testIn.Int3               == testOut.Int3, "Int3 value mismatch");
+				oxAssert(testIn.Int4               == testOut.Int4, "Int4 value mismatch");
+				oxAssert(testIn.Int5               == testOut.Int5, "Int5 value mismatch");
+				oxAssert(testIn.Int6               == testOut.Int6, "Int6 value mismatch");
+				oxAssert(testIn.Int7               == testOut.Int7, "Int7 value mismatch");
+				oxAssert(testIn.Int8               == testOut.Int8, "Int8 value mismatch");
+				oxAssert(testIn.Union.Int          == testOut.Union.Int, "Union.Int value mismatch");
+				oxAssert(testIn.String             == testOut.String, "String value mismatch");
+				oxAssert(testIn.List[0]            == testOut.List[0], "List[0] value mismatch");
+				oxAssert(testIn.List[1]            == testOut.List[1], "List[1] value mismatch");
+				oxAssert(testIn.List[2]            == testOut.List[2], "List[2] value mismatch");
+				oxAssert(testIn.List[3]            == testOut.List[3], "List[3] value mismatch");
+				oxAssert(testIn.EmptyStruct.Bool   == testOut.EmptyStruct.Bool, "EmptyStruct.Bool value mismatch");
+				oxAssert(testIn.EmptyStruct.Int    == testOut.EmptyStruct.Int, "EmptyStruct.Int value mismatch");
+				oxAssert(testIn.EmptyStruct.String == testOut.EmptyStruct.String, "EmptyStruct.String value mismatch");
+				oxAssert(testIn.Struct.Int         == testOut.Struct.Int, "Struct.Int value mismatch");
+				oxAssert(testIn.Struct.String      == testOut.Struct.String, "Struct.String value mismatch");
+				oxAssert(testIn.Struct.Bool        == testOut.Struct.Bool, "Struct.Bool value mismatch");
+
+				return ox::Error(0);
+			}
+		},
+	}
+};
+
+int main(int argc, const char **args) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+	}
+	auto const testName = args[1];
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/event/CMakeLists.txt

@@ -0,0 +1,51 @@
+add_library(
+	OxEvent
+		src/signal.cpp
+)
+
+if(NOT MSVC)
+    target_compile_options(OxEvent PRIVATE -Wsign-conversion)
+    target_compile_options(OxEvent PRIVATE -Wconversion)
+endif()
+
+if(NOT OX_BARE_METAL)
+	set_property(
+		TARGET
+			OxEvent
+		PROPERTY
+			POSITION_INDEPENDENT_CODE ON
+	)
+endif()
+
+target_compile_definitions(
+	OxEvent PUBLIC
+		$<$<BOOL:${OX_USE_STDLIB}>:OX_USE_STDLIB>
+		$<$<BOOL:${OX_NODEBUG}>:OX_NODEBUG>
+)
+
+target_link_libraries(
+	OxEvent PUBLIC
+		OxStd
+)
+
+target_include_directories(
+	OxEvent PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS OxEvent
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+    add_subdirectory(test)
+endif()

src/event/include/ox/event/event.hpp

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "signal.hpp"

src/event/include/ox/event/signal.hpp

@@ -0,0 +1,416 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/assert.hpp>
+#include <ox/std/def.hpp>
+#include <ox/std/defines.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/std/vector.hpp>
+
+namespace ox {
+
+class SignalHandler;
+
+#ifndef OX_OS_BareMetal
+
+namespace detail {
+
+template<typename T>
+struct isError {
+	static constexpr bool value = false;
+};
+
+template<>
+struct isError<Error> {
+	static constexpr bool value = true;
+};
+
+}
+
+template<class... Args>
+class Signal {
+	protected:
+		struct BaseSlot {
+			virtual ~BaseSlot() = default;
+			virtual void call(Args...) = 0;
+			virtual void cleanup(Signal*) noexcept {}
+			[[nodiscard]]
+			virtual const void *receiver() const noexcept { return nullptr; }
+		};
+
+		template<typename F>
+		struct FunctionSlot: public BaseSlot {
+			F f;
+
+			explicit FunctionSlot(F f) {
+				this->f = f;
+			}
+
+			void call(Args... args) final {
+				if constexpr(detail::isError<decltype(f(args...))>::value) {
+					OX_THROW_ERROR(f(args...));
+				} else {
+					f(args...);
+				}
+			}
+		};
+
+		template<typename T, typename Method>
+		struct MethodSlot: public BaseSlot {
+			T m_receiver = nullptr;
+			Method m_methodPtr;
+
+			MethodSlot(T receiver, Method methodPtr) {
+				m_receiver = receiver;
+				m_methodPtr = methodPtr;
+			}
+
+			void call(Args... args) final {
+				if constexpr(detail::isError<decltype((m_receiver->*(m_methodPtr))(args...))>::value) {
+					OX_THROW_ERROR((m_receiver->*(m_methodPtr))(args...));
+				} else {
+					f(args...);
+				}
+			}
+
+			void cleanup(Signal *signal) noexcept final {
+				std::ignore = m_receiver->destruction.disconnectSignal(signal);
+				//if (err) {
+				//	oxErrorf("Signal could not notify receiver that it is being destroyed. Destruction of receiver will cause use-after-free. ({})", toStr(err));
+				//}
+			}
+
+			[[nodiscard]]
+			const void *receiver() const noexcept final {
+				return m_receiver;
+			}
+		};
+
+		template<typename SignalT, typename Method>
+		struct SignalMethodSlot: public BaseSlot {
+			const SignalT *m_receiver = nullptr;
+			Method m_methodPtr;
+
+			SignalMethodSlot(const SignalT *receiver, Method methodPtr) {
+				m_receiver = receiver;
+				m_methodPtr = methodPtr;
+			}
+
+			void call(Args... args) final {
+				if constexpr(detail::isError<decltype((m_receiver->*(m_methodPtr))(args...))>::value) {
+					OX_THROW_ERROR((m_receiver->*(m_methodPtr))(args...));
+				} else {
+					(m_receiver->*(m_methodPtr))(args...);
+				}
+			}
+
+			void cleanup(Signal*) noexcept final {
+			}
+
+			[[nodiscard]]
+			const void *receiver() const noexcept final {
+				return m_receiver;
+			}
+		};
+
+		mutable Vector<UPtr<BaseSlot>> m_slots;
+
+	public:
+		~Signal() noexcept;
+
+		void connect(Error(*f)(Args...)) const noexcept;
+
+		template<typename T, typename Method>
+		void connect(const T *receiver, Method methodPtr) const noexcept;
+
+		template<typename T, typename Method>
+		void connect(T *receiver, Method methodPtr) const noexcept;
+
+		template<class... SubArgs, typename Method>
+		void connect(const Signal<SubArgs...> *receiver, Method methodPtr) const noexcept;
+
+		template<class... SubArgs>
+		Error disconnectSignal(const Signal<SubArgs...> *receiver) const noexcept;
+
+		Error disconnectObject(const void *receiver) const noexcept;
+
+		[[nodiscard]]
+		size_t connectionCnt() const noexcept {
+			return m_slots.size();
+		}
+
+		void emit(Args... args) const;
+
+		Error emitCheckError(Args... args) const noexcept;
+};
+
+extern template class Signal<const SignalHandler*>;
+
+template<class... Args>
+Signal<Args...>::~Signal() noexcept {
+	for (auto &slot : m_slots) {
+		slot->cleanup(this);
+	}
+}
+
+template<class... Args>
+void Signal<Args...>::connect(Error(*f)(Args...)) const noexcept {
+	m_slots.emplace_back(new FunctionSlot<decltype(f)>(f));
+}
+
+template<class... Args>
+template<typename T, typename Method>
+void Signal<Args...>::connect(const T *receiver, Method methodPtr) const noexcept {
+	receiver->destruction.connect(this, &Signal<Error(Args...)>::disconnectObject);
+	m_slots.emplace_back(new MethodSlot<const T*, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<typename T, typename Method>
+void Signal<Args...>::connect(T *receiver, Method methodPtr) const noexcept {
+	receiver->destruction.connect(this, &Signal<Error(Args...)>::disconnectObject);
+	m_slots.emplace_back(new MethodSlot<T*, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<class... SubArgs, typename Method>
+void Signal<Args...>::connect(const Signal<SubArgs...> *receiver, Method methodPtr) const noexcept {
+	m_slots.emplace_back(new SignalMethodSlot<Signal<SubArgs...>, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<class... SubArgs>
+Error Signal<Args...>::disconnectSignal(const Signal<SubArgs...> *receiver) const noexcept {
+	return disconnectObject(receiver);
+}
+
+template<class... Args>
+Error Signal<Args...>::disconnectObject(const void *receiver) const noexcept {
+	for (auto i = 0u; i < m_slots.size(); ++i) {
+		const auto &slot = m_slots[i];
+		if (slot->receiver() == receiver) {
+			OX_RETURN_ERROR(m_slots.erase(i));
+			--i;
+		}
+	}
+	return ox::Error(1, "Signal::disconnectObject: Receiver was not found among this Signal's slots");
+}
+
+template<class... Args>
+void Signal<Args...>::emit(Args... args) const {
+	for (auto &f : m_slots) {
+		f->call(args...);
+	}
+}
+
+template<class... Args>
+Error Signal<Args...>::emitCheckError(Args... args) const noexcept {
+	try {
+		for (auto &f : m_slots) {
+			f->call(args...);
+		}
+		return {};
+	} catch (const ox::Exception &ex) {
+		return ox::Error(ex.errCode, ex.msg, ex.src);
+	}
+}
+
+#else
+
+template<typename T>
+class Signal;
+
+#endif
+
+template<class... Args>
+class Signal<Error(Args...)> {
+	protected:
+		struct BaseSlot {
+			virtual ~BaseSlot() = default;
+			virtual Error call(Args...) noexcept = 0;
+			virtual void cleanup(Signal*) noexcept {}
+			[[nodiscard]]
+			virtual const void *receiver() const noexcept { return nullptr; }
+		};
+
+		struct FunctionSlot: public BaseSlot {
+			Error (*f)(Args...);
+
+			explicit FunctionSlot(Error (*f)(Args...)) noexcept {
+				this->f = f;
+			}
+
+			Error call(Args... args) noexcept final {
+				return f(ox::forward<Args>(args)...);
+			}
+		};
+
+		template<typename T, typename Method>
+		struct MethodSlot: public BaseSlot {
+			T m_receiver = nullptr;
+			Method m_methodPtr;
+
+			MethodSlot(T receiver, Method methodPtr) {
+				m_receiver = receiver;
+				m_methodPtr = methodPtr;
+			}
+
+			Error call(Args... args) noexcept final {
+				return (m_receiver->*(m_methodPtr))(ox::forward<Args>(args)...);
+			}
+
+			void cleanup(Signal *signal) noexcept final {
+				std::ignore = m_receiver->destruction.disconnectSignal(signal);
+				//oxErrorf("{}", toStr(err));
+				//oxAssert(err, "Signal could not notify receiver that it is being destroyed. Destruction of receiver will cause use-after-free.");
+			}
+
+			[[nodiscard]]
+			const void *receiver() const noexcept final {
+				return m_receiver;
+			}
+		};
+
+		template<typename SignalT, typename Method>
+		struct SignalMethodSlot: public BaseSlot {
+			const SignalT *m_receiver = nullptr;
+			Method m_methodPtr;
+
+			SignalMethodSlot(const SignalT *receiver, Method methodPtr) {
+				m_receiver = receiver;
+				m_methodPtr = methodPtr;
+			}
+
+			Error call(Args... args) noexcept final {
+				return (m_receiver->*(m_methodPtr))(ox::forward<Args>(args)...);
+			}
+
+			void cleanup(Signal*) noexcept final {
+			}
+
+			[[nodiscard]]
+			const void *receiver() const noexcept final {
+				return m_receiver;
+			}
+		};
+
+		mutable Vector<UPtr<BaseSlot>> m_slots;
+
+	public:
+		~Signal() noexcept;
+
+		void connect(Error(*f)(Args...)) const noexcept;
+
+		template<typename T, typename Method>
+		void connect(const T *receiver, Method methodPtr) const noexcept;
+
+		template<typename T, typename Method>
+		void connect(T *receiver, Method methodPtr) const noexcept;
+
+		template<class... SubArgs, typename Method>
+		void connect(const Signal<SubArgs...> *receiver, Method methodPtr) const noexcept;
+
+		template<class... SubArgs>
+		Error disconnectSignal(const Signal<SubArgs...> *receiver) const noexcept;
+
+		Error disconnectObject(const void *receiver) const noexcept;
+
+		[[nodiscard]]
+		size_t connectionCnt() const noexcept {
+			return m_slots.size();
+		}
+
+		void emit(Args... args) const noexcept;
+
+		Error emitCheckError(Args... args) const noexcept;
+};
+
+extern template class Signal<Error(const SignalHandler*)>;
+
+class SignalHandler {
+	public:
+		Signal<Error(const SignalHandler*)> destruction;
+
+		constexpr SignalHandler() noexcept = default;
+		SignalHandler(const SignalHandler&) = delete;
+		SignalHandler(SignalHandler&) = delete;
+		SignalHandler(SignalHandler&&) = delete;
+
+		virtual ~SignalHandler() noexcept;
+};
+
+template<class... Args>
+Signal<Error(Args...)>::~Signal() noexcept {
+	for (auto &slot : m_slots) {
+		slot->cleanup(this);
+	}
+}
+
+template<class... Args>
+void Signal<Error(Args...)>::connect(Error(*f)(Args...)) const noexcept {
+	m_slots.emplace_back(new FunctionSlot(f));
+}
+
+template<class... Args>
+template<typename T, typename Method>
+void Signal<Error(Args...)>::connect(const T *receiver, Method methodPtr) const noexcept {
+	receiver->destruction.connect(this, &Signal<Error(Args...)>::disconnectObject);
+	m_slots.emplace_back(new MethodSlot<const T*, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<typename T, typename Method>
+void Signal<Error(Args...)>::connect(T *receiver, Method methodPtr) const noexcept {
+	receiver->destruction.connect(this, &Signal<Error(Args...)>::disconnectObject);
+	m_slots.emplace_back(new MethodSlot<T*, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<class... SubArgs, typename Method>
+void Signal<Error(Args...)>::connect(const Signal<SubArgs...> *receiver, Method methodPtr) const noexcept {
+	m_slots.emplace_back(new SignalMethodSlot<Signal<SubArgs...>, Method>(receiver, methodPtr));
+}
+
+template<class... Args>
+template<class... SubArgs>
+Error Signal<Error(Args...)>::disconnectSignal(const Signal<SubArgs...> *receiver) const noexcept {
+	return disconnectObject(receiver);
+}
+
+template<class... Args>
+Error Signal<Error(Args...)>::disconnectObject(const void *receiver) const noexcept {
+	for (auto i = 0u; i < m_slots.size(); ++i) {
+		const auto &slot = m_slots[i];
+		if (slot->receiver() == receiver) {
+			OX_RETURN_ERROR(m_slots.erase(i));
+			--i;
+		}
+	}
+	return ox::Error(1, "Signal::disconnectObject: Receiver was not found among this Signal's slots");
+}
+
+template<class... Args>
+void Signal<Error(Args...)>::emit(Args... args) const noexcept {
+	for (auto &f : m_slots) {
+		std::ignore = f->call(ox::forward<Args>(args)...);
+	}
+}
+
+template<class... Args>
+Error Signal<Error(Args...)>::emitCheckError(Args... args) const noexcept {
+	for (auto &f : m_slots) {
+		OX_RETURN_ERROR(f->call(ox::forward<Args>(args)...));
+	}
+	return {};
+}
+
+}

src/event/src/signal.cpp

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/event/signal.hpp>
+
+namespace ox {
+
+#ifndef OX_OS_BareMetal
+template class Signal<const SignalHandler*>;
+#endif
+template class Signal<Error(const SignalHandler*)>;
+
+SignalHandler::~SignalHandler() noexcept {
+	destruction.emit(this);
+}
+
+}
+
+/*
+ * 1. ProjectExplorer::fileOpened cannot notify StudioUI that it is being destroyed.
+ * 2. StudioUI tries to unsubscribe from ProjectExplorer::fileOpened upon its destruction.
+ * 3. Segfault
+ */

src/event/test/CMakeLists.txt

@@ -0,0 +1,10 @@
+cmake_minimum_required(VERSION 3.10)
+
+add_executable(
+    EventTest
+        tests.cpp
+)
+
+target_link_libraries(EventTest OxEvent)
+
+add_test("[ox/event] Test 1" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/EventTest "test1")

src/event/test/tests.cpp

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#undef NDEBUG
+
+#include <map>
+#include <functional>
+#include <ox/event/signal.hpp>
+#include <ox/std/std.hpp>
+
+struct TestStruct: public ox::SignalHandler {
+	int value = 0;
+	ox::Error method(int i) noexcept {
+		value = i;
+		return ox::Error(0);
+	}
+};
+
+std::map<ox::StringView, std::function<ox::Error()>> tests = {
+	{
+		"test1",
+		[] {
+			ox::Signal<ox::Error(int)> signal;
+			signal.connect([](int i) -> ox::Error {
+				return ox::Error(i != 5);
+			});
+			TestStruct ts;
+			signal.connect(&ts, &TestStruct::method);
+			OX_RETURN_ERROR(signal.emitCheckError(5));
+			OX_RETURN_ERROR(ox::Error(ts.value != 5));
+			return ox::Error(0);
+		}
+	},
+};
+
+int main(int argc, const char **args) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+	}
+	auto const testName = args[1];
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/fs/CMakeLists.txt

@@ -0,0 +1,74 @@
+if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+	# enable warnings
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wunsafe-buffer-usage")
+endif()
+
+add_library(
+	OxFS
+		src/filestore/filestoretemplate.cpp
+		src/filesystem/filelocation.cpp
+		src/filesystem/pathiterator.cpp
+		src/filesystem/directory.cpp
+		src/filesystem/filesystem.cpp
+		src/filesystem/passthroughfs.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxFS PRIVATE -Wsign-conversion)
+endif()
+
+if(NOT OX_BARE_METAL)
+	set_property(
+		TARGET
+			OxFS
+		PROPERTY
+			POSITION_INDEPENDENT_CODE ON
+	)
+endif()
+
+target_link_libraries(
+	OxFS PUBLIC
+		OxMetalClaw
+)
+
+target_include_directories(
+	OxFS PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+if(NOT OX_BARE_METAL)
+	add_executable(
+		oxfs-tool
+			src/tool.cpp
+	)
+
+	target_link_libraries(
+		oxfs-tool
+			OxFS
+	)
+
+	install(
+		TARGETS
+			oxfs-tool
+		DESTINATION
+			bin
+	)
+endif()
+
+install(
+	TARGETS
+		OxFS
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/fs/include/ox/fs/filestore/filestoretemplate.hpp

@@ -0,0 +1,777 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/fs/ptrarith/nodebuffer.hpp>
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+using InodeId_t = uint64_t;
+using FsSize_t = std::size_t;
+
+struct StatInfo {
+	InodeId_t inode = 0;
+	InodeId_t links = 0;
+	FsSize_t size = 0;
+	uint8_t fileType = 0;
+};
+
+template<typename size_t>
+struct OX_PACKED FileStoreItem: public ptrarith::Item<size_t> {
+	LittleEndian<size_t> id = 0;
+	LittleEndian<uint8_t> fileType = 0;
+	LittleEndian<size_t> links = 0;
+	LittleEndian<size_t> left = 0;
+	LittleEndian<size_t> right = 0;
+
+	FileStoreItem() = default;
+
+	explicit FileStoreItem(size_t size) {
+		this->setSize(size);
+	}
+
+	/**
+	 * @return the size of the data + the size of the Item type
+	 */
+	[[nodiscard]]
+	size_t fullSize() const {
+		return sizeof(*this) + this->size();
+	}
+
+	ptrarith::Ptr<uint8_t, std::size_t> data() {
+		return ptrarith::Ptr<uint8_t, std::size_t>(this, this->fullSize(), sizeof(*this), this->size());
+	}
+
+};
+
+
+template<typename size_t>
+class FileStoreTemplate {
+
+	public:
+		using InodeId_t = size_t;
+
+	private:
+		using Item = FileStoreItem<size_t>;
+		using ItemPtr = typename ptrarith::NodeBuffer<size_t, FileStoreItem<size_t>>::ItemPtr;
+		using Buffer = ptrarith::NodeBuffer<size_t, FileStoreItem<size_t>>;
+
+		static constexpr InodeId_t ReservedInodeEnd = 100;
+
+		struct OX_PACKED FileStoreData {
+			LittleEndian<size_t> rootNode = 0;
+			Random random;
+		};
+
+		size_t m_buffSize = 0;
+		mutable Buffer *m_buffer = nullptr;
+
+	public:
+		FileStoreTemplate() = default;
+
+		FileStoreTemplate(void *buff, std::size_t buffSize);
+
+		static Error format(void *buffer, std::size_t bufferSize);
+
+		Error setSize(std::size_t buffSize);
+
+		Error incLinks(uint64_t id);
+
+		Error decLinks(uint64_t id);
+
+		Error write(uint64_t id64, const void *data, FsSize_t dataSize, uint8_t fileType = 0);
+
+		Error remove(uint64_t id);
+
+		Error read(uint64_t id, void *out, FsSize_t outSize, FsSize_t *size = nullptr) const;
+
+		Error read(uint64_t id, FsSize_t readStart, FsSize_t readSize, void *data, FsSize_t *size = nullptr) const;
+
+		ptrarith::Ptr<uint8_t, std::size_t> read(uint64_t id) const;
+
+		/**
+		 * Reads the "file" at the given id. You are responsible for freeing
+		 * the data when done with it.
+		 * @param id id of the "file"
+		 * @param readStart where in the data to start reading
+		 * @param readSize how much data to read
+		 * @param data pointer to the pointer where the data is stored
+		 * @param size pointer to a value that will be assigned the size of data
+		 * @return 0 if read is a success
+		 */
+		template<typename T>
+		Error read(uint64_t id, FsSize_t readStart,
+		           FsSize_t readSize, T *data,
+		           FsSize_t *size) const;
+
+		Result<StatInfo> stat(uint64_t id) const;
+
+		Error resize();
+
+		Error resize(std::size_t size, void *newBuff = nullptr);
+
+		[[nodiscard]]
+		InodeId_t spaceNeeded(FsSize_t size) const;
+
+		[[nodiscard]]
+		InodeId_t size() const;
+
+		[[nodiscard]]
+		InodeId_t available() const;
+
+		[[nodiscard]]
+		char *buff();
+
+		Error walk(Error(*cb)(uint8_t, uint64_t, uint64_t));
+
+		Result<InodeId_t> generateInodeId();
+
+		bool valid() const;
+
+		Error compact();
+
+	private:
+		FileStoreData *fileStoreData() const;
+
+		/**
+		 * Places the given Item at the given ID. If it already exists, the
+		 * existing value will be overwritten.
+		 */
+		Error placeItem(ItemPtr item);
+
+		/**
+		 * Places the given Item at the given ID. If it already exists, the
+		 * existing value will be overwritten.
+		 */
+		Error placeItem(ItemPtr root, ItemPtr item, int depth = 0);
+
+		/**
+		 * Removes the given Item at the given ID. If it already exists, the
+		 * existing value will be overwritten.
+		 */
+		Error unplaceItem(ItemPtr item);
+
+		/**
+		 * Removes the given Item at the given ID. If it already exists, the
+		 * existing value will be overwritten.
+		 */
+		Error unplaceItem(ItemPtr root, ItemPtr item, int depth = 0);
+
+		Error remove(ItemPtr item);
+
+		/**
+		 * Finds the parent an inode by its ID.
+		 */
+		ItemPtr findParent(ItemPtr item, size_t id, size_t oldAddr) const;
+
+		/**
+		 * Finds an inode by its ID.
+		 */
+		ItemPtr find(ItemPtr item, InodeId_t id, int depth = 0) const;
+
+		/**
+		 * Finds an inode by its ID.
+		 */
+		ItemPtr find(InodeId_t id) const;
+
+		/**
+		 * Gets the root inode.
+		 */
+		ItemPtr rootInode();
+
+		bool canWrite(ItemPtr existing, std::size_t size);
+
+};
+
+template<typename size_t>
+FileStoreTemplate<size_t>::FileStoreTemplate(void *buff, std::size_t buffSize) {
+	m_buffSize = static_cast<size_t>(buffSize);
+	m_buffer = reinterpret_cast<ptrarith::NodeBuffer<size_t, FileStoreItem<size_t>>*>(buff);
+	if (!m_buffer->valid(m_buffSize)) {
+		m_buffSize = 0;
+		m_buffer = nullptr;
+	}
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::format(void *buffer, std::size_t bufferSize) {
+	auto nb = new (buffer) Buffer(static_cast<size_t>(bufferSize));
+	auto fsData = nb->malloc(sizeof(FileStoreData)).value;
+	if (!fsData.valid()) {
+		oxTrace("ox.fs.FileStoreTemplate.format.fail", "Could not read data section of FileStoreData");
+		return ox::Error(1, "Could not read data section of FileStoreData");
+	}
+	auto data = nb->template dataOf<FileStoreData>(fsData);
+	if (!data.valid()) {
+		oxTrace("ox.fs.FileStoreTemplate.format.fail", "Could not read data section of FileStoreData");
+		return ox::Error(1, "Could not read data section of FileStoreData");
+	}
+	new (data) FileStoreData;
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::setSize(std::size_t size) {
+	if (m_buffSize >= size) {
+		return m_buffer->setSize(static_cast<size_t>(size));
+	}
+	return ox::Error(1);
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::incLinks(uint64_t id) {
+	OX_REQUIRE_M(item, find(static_cast<size_t>(id)).validate());
+	++item->links;
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::decLinks(uint64_t id) {
+	OX_REQUIRE_M(item, find(static_cast<size_t>(id)).validate());
+	--item->links;
+	if (item->links == 0) {
+		OX_RETURN_ERROR(remove(item));
+	}
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::write(uint64_t id64, const void *data, FsSize_t dataSize, uint8_t fileType) {
+	const auto id = static_cast<size_t>(id64);
+	oxTracef("ox.fs.FileStoreTemplate.write", "Attempting to write to inode {}", id);
+	auto existing = find(id);
+	if (!canWrite(existing, dataSize)) {
+		OX_RETURN_ERROR(compact());
+		existing = find(id);
+	}
+
+	if (canWrite(existing, dataSize)) {
+		// delete the old node if it exists
+		if (existing.valid()) {
+			oxTracef("ox.fs.FileStoreTemplate.write", "Freeing old version of inode found at offset: {}", existing.offset());
+			auto err = m_buffer->free(existing);
+			if (err) {
+				oxTrace("ox.fs.FileStoreTemplate.write.fail", "Free of old version of inode failed");
+				return err;
+			}
+			existing = nullptr;
+		}
+		// write the given data
+		auto dest = m_buffer->malloc(dataSize).value;
+		// if first malloc failed, compact and try again
+		if (!dest.valid()) {
+			oxTrace("ox.fs.FileStoreTemplate.write", "Allocation failed, compacting");
+			OX_RETURN_ERROR(compact());
+			dest = m_buffer->malloc(dataSize).value;
+		}
+		if (dest.valid()) {
+			oxTrace("ox.fs.FileStoreTemplate.write", "Memory allocated");
+			dest->id = id;
+			dest->fileType = fileType;
+			auto destData = m_buffer->template dataOf<uint8_t>(dest);
+			if (destData.valid()) {
+				oxAssert(destData.size() == dataSize, "Allocation size does not match data.");
+				// write data if any was provided
+				if (data != nullptr) {
+					ox::memcpy(destData, data, dest->size());
+					oxTrace("ox.fs.FileStoreTemplate.write", "Data written");
+				}
+				auto fsData = fileStoreData();
+				if (fsData) {
+					oxTracef("ox.fs.FileStoreTemplate.write", "Searching for root node at {}", fsData->rootNode.get());
+					auto root = m_buffer->ptr(fsData->rootNode);
+					if (root.valid()) {
+						oxTracef("ox.fs.FileStoreTemplate.write",
+						         "Placing {} on {} at {}", dest->id.get(), root->id.get(), destData.offset());
+						return placeItem(dest);
+					} else {
+						oxTracef("ox.fs.FileStoreTemplate.write",
+						        "Initializing root inode: {} (offset: {}, data size: {})",
+						        dest->id.get(), dest.offset(), destData.size());
+						fsData->rootNode = dest.offset();
+						oxTracef("ox.fs.FileStoreTemplate.write", "Root inode: {}", dest->id.get());
+						return {};
+					}
+				} else {
+					oxTrace("ox.fs.FileStoreTemplate.write.fail", "Could not place item due to absence of FileStore header.");
+				}
+			}
+		}
+		OX_RETURN_ERROR(m_buffer->free(dest));
+	}
+	return ox::Error(1);
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::remove(uint64_t id) {
+	return remove(find(static_cast<size_t>(id)));
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::read(uint64_t id, void *out, FsSize_t outSize, FsSize_t *size) const {
+	oxTracef("ox.fs.FileStoreTemplate.read", "Attempting to read inode {}", id);
+	auto src = find(static_cast<size_t>(id));
+	// error check
+	if (!src.valid()) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not find requested item: {}", id);
+		return ox::Error(1, "Could not find requested item");
+	}
+
+	auto srcData = m_buffer->template dataOf<uint8_t>(src);
+	oxTracef("ox.fs.FileStoreTemplate.read.found", "{} found at {} with data section at {}",
+	         id, src.offset(), srcData.offset());
+	oxTracef("ox.fs.FileStoreTemplate.read.outSize", "{} {} {}", srcData.offset(), srcData.size(), outSize);
+
+	// error check
+	if (!(srcData.valid() && srcData.size() <= outSize)) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not read data section of item: {}", id);
+		oxTracef("ox.fs.FileStoreTemplate.read.fail",
+		         "Item data section size: {}, Expected size: {}", srcData.size(), outSize);
+		return ox::Error(1, "Invalid inode");
+	}
+
+	ox::memcpy(out, srcData, srcData.size());
+	if (size) {
+		*size = src.size();
+	}
+
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::read(uint64_t id, FsSize_t readStart, FsSize_t readSize, void *out, FsSize_t *size) const {
+	oxTracef("ox.fs.FileStoreTemplate.read", "Attempting to read from inode {}", id);
+	auto src = find(static_cast<size_t>(id));
+	// error check
+	if (!src.valid()) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not find requested item: {}", id);
+		return ox::Error(1);
+	}
+
+	auto srcData = m_buffer->template dataOf<uint8_t>(src);
+	oxTracef("ox.fs.FileStoreTemplate.read.found", "{} found at {} with data section at {}",
+	         id, src.offset(), srcData.offset());
+	oxTracef("ox.fs.FileStoreTemplate.read.readSize", "{} {} {}", srcData.offset(), srcData.size(), readSize);
+
+	// error check
+	if (!(srcData.valid() && srcData.size() - readStart <= readSize)) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not read data section of item: {}", id);
+		oxTracef("ox.fs.FileStoreTemplate.read.fail",
+		         "Item data section size: {}, Expected size: {}", srcData.size(), readSize);
+		return ox::Error(1);
+	}
+
+	ox::memcpy(out, srcData.get() + readStart, readSize);
+	if (size) {
+		*size = src.size();
+	}
+
+	return {};
+}
+
+template<typename size_t>
+template<typename T>
+Error FileStoreTemplate<size_t>::read(uint64_t id, FsSize_t readStart,
+                                      FsSize_t readSize, T *out, FsSize_t *size) const {
+	oxTracef("ox.fs.FileStoreTemplate.read", "Attempting to read from inode {}", id);
+	auto src = find(static_cast<size_t>(id));
+	// error check
+	if (!src.valid()) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not find requested item: {}", id);
+		return ox::Error(1);
+	}
+
+	auto srcData = m_buffer->template dataOf<uint8_t>(src);
+	oxTracef("ox.fs.FileStoreTemplate.read.found", "{} found at {} with data section at {}",
+	         id, src.offset(), srcData.offset());
+	oxTracef("ox.fs.FileStoreTemplate.read.readSize", "{} {} {}", srcData.offset(), srcData.size(), readSize);
+
+	// error check
+	if (!(srcData.valid() && srcData.size() - readStart <= readSize)) {
+		oxTracef("ox.fs.FileStoreTemplate.read.fail", "Could not read data section of item: {}", id);
+		oxTracef("ox.fs.FileStoreTemplate.read.fail",
+		         "Item data section size: {}, Expected size: {}", srcData.size(), readSize);
+		return ox::Error(1);
+	}
+
+	ox::memcpy(out, srcData.get() + readStart, readSize);
+	if (size) {
+		*size = src.size();
+	}
+
+	return {};
+}
+
+template<typename size_t>
+ptrarith::Ptr<uint8_t, std::size_t> FileStoreTemplate<size_t>::read(uint64_t id) const {
+	auto item = find(static_cast<size_t>(id));
+	if (item.valid()) {
+		return item->data();
+	} else {
+		return nullptr;
+	}
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::resize() {
+	OX_RETURN_ERROR(compact());
+	const auto newSize = static_cast<std::size_t>(size() - available());
+	oxTracef("ox.fs.FileStoreTemplate.resize", "resize to: {}", newSize);
+	OX_RETURN_ERROR(m_buffer->setSize(newSize));
+	oxTracef("ox.fs.FileStoreTemplate.resize", "resized to: {}", m_buffer->size());
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::resize(std::size_t size, void *newBuff) {
+	if (m_buffer->size() > size) {
+		return ox::Error{1, "new buffer is too small for existing data"};
+	}
+	m_buffSize = static_cast<size_t>(size);
+	if (newBuff) {
+		m_buffer = static_cast<Buffer*>(newBuff);
+		OX_RETURN_ERROR(m_buffer->setSize(static_cast<size_t>(size)));
+	}
+	return {};
+}
+
+template<typename size_t>
+Result<StatInfo> FileStoreTemplate<size_t>::stat(uint64_t id) const {
+	OX_REQUIRE(inode, find(static_cast<size_t>(id)).validate());
+	return StatInfo {
+		id,
+		inode->links,
+		inode->size(),
+		inode->fileType,
+	};
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::InodeId_t FileStoreTemplate<size_t>::spaceNeeded(FsSize_t size) const {
+	return m_buffer->spaceNeeded(size);
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::InodeId_t FileStoreTemplate<size_t>::size() const {
+	return m_buffer->size();
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::InodeId_t FileStoreTemplate<size_t>::available() const {
+	return m_buffer->available();
+}
+
+template<typename size_t>
+char *FileStoreTemplate<size_t>::buff() {
+	return reinterpret_cast<char*>(m_buffer);
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::walk(Error(*cb)(uint8_t, uint64_t, uint64_t)) {
+	for (auto i = m_buffer->iterator(); i.valid(); i.next()) {
+		OX_RETURN_ERROR(cb(i->fileType, i.ptr().offset(), i.ptr().end()));
+	}
+	return {};
+}
+
+template<typename size_t>
+Result<typename FileStoreTemplate<size_t>::InodeId_t> FileStoreTemplate<size_t>::generateInodeId() {
+	auto fsData = fileStoreData();
+	if (!fsData) {
+		return ox::Error(1);
+	}
+	for (auto i = 0; i < 100; i++) {
+		auto inode = static_cast<typename FileStoreTemplate<size_t>::InodeId_t>(fsData->random.gen() % MaxValue<InodeId_t>);
+		if (inode > ReservedInodeEnd && !find(static_cast<size_t>(inode)).valid()) {
+			return inode;
+		}
+	}
+	return ox::Error(2);
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::compact() {
+	auto isFirstItem = true;
+	return m_buffer->compact([this, &isFirstItem](uint64_t oldAddr, ItemPtr item) -> Error {
+		if (isFirstItem) {
+			isFirstItem = false;
+			return {};
+		}
+		if (!item.valid()) {
+			return ox::Error(1);
+		}
+		oxTracef("ox.fs.FileStoreTemplate.compact.moveItem", "Moving Item: {} from {} to {}", item->id.get(), oldAddr, item.offset());
+		// update rootInode if this is it
+		auto fsData = fileStoreData();
+		if (fsData && oldAddr == fsData->rootNode) {
+			fsData->rootNode = item.offset();
+		}
+		auto parent = findParent(rootInode(), item->id, static_cast<size_t>(oldAddr));
+		oxAssert(parent.valid() || rootInode() == item.offset(),
+		         "Parent inode not found for item that should have parent.");
+		if (parent.valid()) {
+			if (parent->left == oldAddr) {
+				parent->left = item;
+			} else if (parent->right == oldAddr) {
+				parent->right = item;
+			}
+		}
+		return {};
+	});
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::FileStoreData *FileStoreTemplate<size_t>::fileStoreData() const {
+	auto first = m_buffer->firstItem();
+	if (first.valid()) {
+		auto data = first->data();
+		if (data.valid()) {
+			return reinterpret_cast<FileStoreData*>(data.get());
+		}
+	}
+	return nullptr;
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::placeItem(ItemPtr item) {
+	auto fsData = fileStoreData();
+	if (!fsData) {
+		return ox::Error(1);
+	}
+	OX_REQUIRE_M(root, m_buffer->ptr(fsData->rootNode).validate());
+	if (root->id == item->id) {
+		fsData->rootNode = item;
+		item->left = root->left;
+		item->right = root->right;
+		oxTracef("ox.fs.FileStoreTemplate.placeItem", "Overwrote Root Item: {}", item->id.get());
+		return {};
+	} else {
+		return placeItem(root, item);
+	}
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::placeItem(ItemPtr root, ItemPtr item, int depth) {
+	if (depth > 5000) {
+		oxTrace("ox.fs.FileStoreTemplate.placeItem.fail", "Excessive recursion depth, stopping before stack overflow.");
+		return ox::Error(2);
+	}
+	if (item->id > root->id) {
+		auto right = m_buffer->ptr(root->right);
+		if (!right.valid() || right->id == item->id) {
+			root->right = item.offset();
+			if (right.valid()) {
+				item->left = right->left;
+				item->right = right->right;
+			}
+			oxTracef("ox.fs.FileStoreTemplate.placeItem", "Placed Item: {}", item->id.get());
+			return {};
+		} else {
+			return placeItem(right, item, depth + 1);
+		}
+	} else if (item->id < root->id) {
+		auto left = m_buffer->ptr(root->left);
+		if (!left.valid() || left->id == item->id) {
+			root->left = item.offset();
+			if (left.valid()) {
+				item->left = left->left;
+				item->right = left->right;
+			}
+			oxTracef("ox.fs.FileStoreTemplate.placeItem", "Placed Item: {}", item->id.get());
+			return {};
+		} else {
+			return placeItem(left, item, depth + 1);
+		}
+	} else {
+		oxTrace("ox.fs.FileStoreTemplate.placeItem.fail", "Cannot insert an item on itself.");
+		return ox::Error(1, "Cannot insert an item on itself.");
+	}
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::unplaceItem(ItemPtr item) {
+	auto fsData = fileStoreData();
+	if (!fsData) {
+		return ox::Error(1);
+	}
+	OX_REQUIRE_M(root, m_buffer->ptr(fsData->rootNode).validate());
+	if (root->id == item->id) {
+		item->left = root->left;
+		item->right = root->right;
+		auto left = m_buffer->ptr(item->left);
+		auto right = m_buffer->ptr(item->right);
+		if (right.valid()) {
+			auto oldRoot = fsData->rootNode;
+			fsData->rootNode = item->right;
+			if (left.valid()) {
+				auto err = placeItem(left);
+				// undo if unable to place the left side of the tree
+				if (err) {
+					fsData->rootNode = oldRoot;
+					return err;
+				}
+			}
+		} else if (left.valid()) {
+			fsData->rootNode = item->left;
+		} else {
+			fsData->rootNode = 0;
+		}
+		return {};
+	} else {
+		return unplaceItem(root, item);
+	}
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::unplaceItem(ItemPtr root, ItemPtr item, int depth) {
+	if (depth >= 5000) {
+		oxTrace("ox.fs.FileStoreTemplate.unplaceItem.fail", "Excessive recursion depth, stopping before stack overflow.");
+		return ox::Error(1, "Excessive recursion depth, stopping before stack overflow.");
+	}
+	if (item->id > root->id) {
+		auto right = m_buffer->ptr(root->right);
+		if (right->id == item->id) {
+			root->right = 0;
+			oxTracef("ox.fs.FileStoreTemplate.unplaceItem", "Unplaced Item: {}", item->id.get());
+		} else {
+			return unplaceItem(right, item, depth + 1);
+		}
+	} else if (item->id < root->id) {
+		auto left = m_buffer->ptr(root->left);
+		if (left->id == item->id) {
+			root->left = 0;
+			oxTracef("ox.fs.FileStoreTemplate.unplaceItem", "Unplaced Item: {}", item->id.get());
+		} else {
+			return unplaceItem(left, item, depth + 1);
+		}
+	} else {
+		return ox::Error(1);
+	}
+	if (item->right) {
+		OX_RETURN_ERROR(placeItem(m_buffer->ptr(item->right)));
+	}
+	if (item->left) {
+		OX_RETURN_ERROR(placeItem(m_buffer->ptr(item->left)));
+	}
+	return {};
+}
+
+template<typename size_t>
+Error FileStoreTemplate<size_t>::remove(ItemPtr item) {
+	if (item.valid()) {
+		OX_RETURN_ERROR(unplaceItem(item));
+		OX_RETURN_ERROR(m_buffer->free(item));
+		return {};
+	}
+	return ox::Error(1);
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::ItemPtr FileStoreTemplate<size_t>::findParent(ItemPtr item, size_t id, size_t oldAddr) const {
+	// This is a little bit confusing. findParent uses the inode ID to find
+	// where the target ID should be, but the actual address of that item is
+	// currently invalid, so we check it against what is known to be the old
+	// address of the item to confirm that we have the right item.
+	if (item.valid()) {
+		if (id > item->id) {
+			if (item->right == oldAddr) {
+				return item;
+			} else {
+				auto right = m_buffer->ptr(item->right);
+				return findParent(right, id, oldAddr);
+			}
+		} else if (id < item->id) {
+			if (item->left == oldAddr) {
+				return item;
+			} else {
+				auto left = m_buffer->ptr(item->left);
+				return findParent(left, id, oldAddr);
+			}
+		}
+	}
+	return nullptr;
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::ItemPtr FileStoreTemplate<size_t>::find(ItemPtr item, InodeId_t id, int depth) const {
+	if (depth > 5000) {
+		oxTracef("ox.fs.FileStoreTemplate.find.fail", "Excessive recursion depth, stopping before stack overflow. Search for: {}", id);
+		return nullptr;
+	}
+	if (!item.valid()) {
+		oxTrace("ox.fs.FileStoreTemplate.find.fail", "item invalid");
+		return nullptr;
+	}
+	// do search
+	if (id > item->id) {
+		oxTracef("ox.fs.FileStoreTemplate.find", "Not a match, searching on {}", item->right.get());
+		return find(m_buffer->ptr(item->right), id, depth + 1);
+	} else if (id < item->id) {
+		oxTracef("ox.fs.FileStoreTemplate.find", "Not a match, searching on {}", item->left.get());
+		return find(m_buffer->ptr(item->left), id, depth + 1);
+	} else if (id == item->id) {
+		oxTracef("ox.fs.FileStoreTemplate.find", "Found {} at {}", id, item.offset());
+		return item;
+	}
+	return nullptr;
+}
+
+template<typename size_t>
+typename FileStoreTemplate<size_t>::ItemPtr FileStoreTemplate<size_t>::find(InodeId_t id) const {
+	oxTracef("ox.fs.FileStoreTemplate.find", "Searching for inode: {}", id);
+	auto fsData = fileStoreData();
+	if (fsData) {
+		auto root = m_buffer->ptr(fsData->rootNode);
+		if (root.valid()) {
+			auto item = find(root, id);
+			return item;
+		} else {
+			oxTrace("ox.fs.FileStoreTemplate.find.fail", "No root node");
+		}
+	} else {
+		oxTrace("ox.fs.FileStoreTemplate.find.fail", "No FileStore Data");
+	}
+	return nullptr;
+}
+
+/**
+ * Gets the root inode.
+ */
+template<typename size_t>
+typename FileStoreTemplate<size_t>::ItemPtr FileStoreTemplate<size_t>::rootInode() {
+	auto fsData = fileStoreData();
+	if (fsData) {
+		return m_buffer->ptr(fsData->rootNode);
+	} else {
+		return nullptr;
+	}
+}
+
+template<typename size_t>
+bool FileStoreTemplate<size_t>::canWrite(ItemPtr existing, std::size_t size) {
+	const auto sz = static_cast<size_t>(size);
+	return existing.size() >= sz || m_buffer->spaceNeeded(sz) <= m_buffer->available();
+}
+
+template<typename size_t>
+bool FileStoreTemplate<size_t>::valid() const {
+	return m_buffer;
+}
+
+extern template class FileStoreTemplate<uint16_t>;
+extern template class FileStoreTemplate<uint32_t>;
+
+using FileStore16 = FileStoreTemplate<uint16_t>;
+using FileStore32 = FileStoreTemplate<uint32_t>;
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/include/ox/fs/filesystem/directory.hpp

@@ -0,0 +1,339 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/fs/filesystem/pathiterator.hpp>
+#include <ox/fs/filestore/filestoretemplate.hpp>
+#include <ox/fs/ptrarith/nodebuffer.hpp>
+#include <ox/std/byteswap.hpp>
+
+#include "types.hpp"
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+template<typename InodeId_t>
+struct OX_PACKED DirectoryEntry {
+
+	public:
+		struct OX_PACKED DirectoryEntryData {
+			// DirectoryEntry fields
+			LittleEndian<InodeId_t> inode = 0;
+			char name[MaxFileNameLength];
+
+			static constexpr std::size_t spaceNeeded(std::size_t chars) {
+				return offsetof(DirectoryEntryData, name) + chars;
+			}
+
+		};
+
+		// NodeBuffer fields
+		LittleEndian<InodeId_t> prev = 0;
+		LittleEndian<InodeId_t> next = 0;
+
+
+	private:
+		LittleEndian<InodeId_t> m_bufferSize = sizeof(DirectoryEntry);
+
+	public:
+		constexpr DirectoryEntry() noexcept = default;
+
+		Error init(InodeId_t inode, ox::StringViewCR name, size_t bufferSize) noexcept {
+			oxTracef("ox.fs.DirectoryEntry.init", "inode: {}, name: {}, bufferSize: {}", inode, name, bufferSize);
+			m_bufferSize = static_cast<InodeId_t>(bufferSize);
+			auto d = data();
+			if (d.valid()) {
+				d->inode = inode;
+				auto const maxStrSz = bufferSize - 1 - sizeof(*this);
+				ox::strncpy(d->name, name.data(), ox::min(maxStrSz, name.size()));
+				return {};
+			}
+			return ox::Error(1);
+		}
+
+		ptrarith::Ptr<DirectoryEntryData, InodeId_t> data() noexcept {
+			oxTracef("ox.fs.DirectoryEntry.data", "{} {} {}", this->fullSize(), sizeof(*this), this->size());
+			return ptrarith::Ptr<DirectoryEntryData, InodeId_t>(this, this->fullSize(), sizeof(*this), this->size(), this->size());
+		}
+
+		/**
+		 * @return the size of the data + the size of the Item type
+		 */
+		[[nodiscard]]
+		InodeId_t fullSize() const {
+			return m_bufferSize;
+		}
+
+		[[nodiscard]]
+		InodeId_t size() const {
+			return fullSize() - static_cast<InodeId_t>(sizeof(*this));
+		}
+
+		void setSize(std::size_t) {
+			// ignore set value
+		}
+
+		static constexpr std::size_t spaceNeeded(std::size_t chars) {
+			return sizeof(DirectoryEntry) + offsetof(DirectoryEntryData, name) + chars;
+		}
+
+};
+
+
+template<typename FileStore, typename InodeId_t>
+class Directory {
+
+	private:
+		using Buffer = ptrarith::NodeBuffer<InodeId_t, DirectoryEntry<InodeId_t>>;
+
+		InodeId_t m_inodeId = 0;
+		std::size_t m_size = 0;
+		FileStore m_fs;
+
+	public:
+		Directory() noexcept = default;
+
+		Directory(FileStore fs, uint64_t inode) noexcept;
+
+		/**
+		 * Initializes Directory.
+		 */
+		Error init() noexcept;
+
+		Error mkdir(PathIterator path, bool parents);
+
+		/**
+		 * @param parents indicates the operation should create non-existent directories in the path, like mkdir -p
+		 */
+		Error write(PathIterator path, uint64_t inode64) noexcept;
+
+		Error remove(PathIterator path) noexcept;
+
+		template<typename F>
+		Error ls(F cb) noexcept;
+
+		[[nodiscard]]
+		Result<typename FileStore::InodeId_t> findEntry(const StringView &name) const noexcept;
+
+		[[nodiscard]]
+		Result<typename FileStore::InodeId_t> find(PathIterator path) const noexcept;
+
+};
+
+template<typename FileStore, typename InodeId_t>
+Directory<FileStore, InodeId_t>::Directory(FileStore fs, uint64_t inodeId) noexcept {
+	m_fs = fs;
+	m_inodeId = static_cast<InodeId_t>(inodeId);
+	auto buff = m_fs.read(static_cast<InodeId_t>(inodeId)).template to<Buffer>();
+	if (buff.valid()) {
+		m_size = buff.size();
+	}
+}
+
+template<typename FileStore, typename InodeId_t>
+Error Directory<FileStore, InodeId_t>::init() noexcept {
+	constexpr auto Size = sizeof(Buffer);
+	oxTracef("ox.fs.Directory.init", "Initializing Directory with Inode ID: {}", m_inodeId);
+	OX_RETURN_ERROR(m_fs.write(m_inodeId, nullptr, Size, static_cast<uint8_t>(FileType::Directory)));
+	auto buff = m_fs.read(m_inodeId).template to<Buffer>();
+	if (!buff.valid()) {
+		m_size = 0;
+		return ox::Error(1);
+	}
+	new (buff) Buffer(Size);
+	m_size = Size;
+	return {};
+}
+
+template<typename FileStore, typename InodeId_t>
+Error Directory<FileStore, InodeId_t>::mkdir(PathIterator path, bool parents) {
+	if (path.valid()) {
+		oxTrace("ox.fs.Directory.mkdir", path.fullPath());
+		// determine if already exists
+		ox::StringView name;
+		OX_RETURN_ERROR(path.get(name));
+		auto childInode = find(PathIterator(name));
+		if (!childInode.ok()) {
+			// if this is not the last item in the path and parents is disabled,
+			// return an error
+			if (!parents && path.hasNext()) {
+				return ox::Error(1);
+			}
+			childInode = m_fs.generateInodeId();
+			oxTracef("ox.fs.Directory.mkdir", "Generated Inode ID: {}", childInode.value);
+			oxLogError(childInode.error);
+			OX_RETURN_ERROR(childInode.error);
+			// initialize the directory
+			Directory<FileStore, InodeId_t> child(m_fs, childInode.value);
+			OX_RETURN_ERROR(child.init());
+			auto err = write(PathIterator(name), childInode.value);
+			if (err) {
+				oxLogError(err);
+				// could not index the directory, delete it
+				oxLogError(m_fs.remove(childInode.value));
+				return err;
+			}
+		}
+		Directory<FileStore, InodeId_t> child(m_fs, childInode.value);
+		if (path.hasNext()) {
+			OX_RETURN_ERROR(child.mkdir(path.next(), parents));
+		}
+	}
+	return {};
+}
+
+template<typename FileStore, typename InodeId_t>
+Error Directory<FileStore, InodeId_t>::write(PathIterator path, uint64_t inode64) noexcept {
+	const auto inode = static_cast<InodeId_t>(inode64);
+	ox::StringView name;
+	if (path.next().hasNext()) { // not yet at target directory, recurse to next one
+		oxTracef("ox.fs.Directory.write", "Attempting to write to next sub-Directory: {} of {}",
+		         name, path.fullPath());
+		OX_RETURN_ERROR(path.get(name));
+		OX_REQUIRE(nextChild, findEntry(name));
+		oxTracef("ox.fs.Directory.write", "{}: {}", name, nextChild);
+		if (nextChild) {
+			return Directory(m_fs, nextChild).write(path.next(), inode);
+		} else {
+			oxTracef("ox.fs.Directory.write", "{} not found and not allowed to create it.", name);
+			return ox::Error(1, "File not found and not allowed to create it.");
+		}
+	} else {
+		oxTrace("ox.fs.Directory.write", path.fullPath());
+		OX_RETURN_ERROR(path.next(name));
+		// insert the new entry on this directory
+		// get the name
+		// find existing version of directory
+		oxTracef("ox.fs.Directory.write", "Searching for directory inode {}", m_inodeId);
+		OX_REQUIRE(oldStat, m_fs.stat(m_inodeId));
+		oxTracef("ox.fs.Directory.write", "Found existing directory of size {}", oldStat.size);
+		auto old = m_fs.read(m_inodeId).template to<Buffer>();
+		if (!old.valid()) {
+			oxTrace("ox.fs.Directory.write.fail", "Could not read existing version of Directory");
+			return ox::Error(1, "Could not read existing version of Directory");
+		}
+		const auto pathSize = name.size() + 1;
+		const auto entryDataSize = DirectoryEntry<InodeId_t>::DirectoryEntryData::spaceNeeded(pathSize);
+		const auto newSize = oldStat.size + Buffer::spaceNeeded(entryDataSize);
+		auto cpy = ox_malloca(newSize, Buffer, *old, oldStat.size);
+		if (cpy == nullptr) {
+			oxTrace("ox.fs.Directory.write.fail", "Could not allocate memory for copy of Directory");
+			return ox::Error(1, "Could not allocate memory for copy of Directory");
+		}
+		OX_RETURN_ERROR(cpy->setSize(newSize));
+		auto val = cpy->malloc(entryDataSize).value;
+		if (!val.valid()) {
+			oxTrace("ox.fs.Directory.write.fail", "Could not allocate memory for new directory entry");
+			return ox::Error(1, "Could not allocate memory for new directory entry");
+		}
+		oxTracef("ox.fs.Directory.write", "Attempting to write Directory entry: {}", name);
+		OX_RETURN_ERROR(val->init(inode, name, val.size()));
+		return m_fs.write(m_inodeId, cpy.get(), cpy->size(), static_cast<uint8_t>(FileType::Directory));
+	}
+}
+
+template<typename FileStore, typename InodeId_t>
+Error Directory<FileStore, InodeId_t>::remove(PathIterator path) noexcept {
+	ox::StringView name;
+	OX_RETURN_ERROR(path.get(name));
+	oxTrace("ox.fs.Directory.remove", name);
+	auto buff = m_fs.read(m_inodeId).template to<Buffer>();
+	if (buff.valid()) {
+		oxTrace("ox.fs.Directory.remove", "Found directory buffer.");
+		for (auto i = buff->iterator(); i.valid(); i.next()) {
+			auto data = i->data();
+			if (data.valid()) {
+				if (name == data->name) {
+					OX_RETURN_ERROR(buff->free(i));
+				}
+			} else {
+				oxTrace("ox.fs.Directory.remove", "INVALID DIRECTORY ENTRY");
+			}
+		}
+	} else {
+		oxTrace("ox.fs.Directory.remove.fail", "Could not find directory buffer");
+		return ox::Error(1, "Could not find directory buffer");
+	}
+	return {};
+}
+
+template<typename FileStore, typename InodeId_t>
+template<typename F>
+Error Directory<FileStore, InodeId_t>::ls(F cb) noexcept {
+	oxTrace("ox.fs.Directory.ls");
+	auto buff = m_fs.read(m_inodeId).template to<Buffer>();
+	if (!buff.valid()) {
+		oxTrace("ox.fs.Directory.ls.fail", "Could not directory buffer");
+		return ox::Error(1, "Could not directory buffer");
+	}
+	oxTrace("ox.fs.Directory.ls", "Found directory buffer.");
+	for (auto i = buff->iterator(); i.valid(); i.next()) {
+		auto data = i->data();
+		if (data.valid()) {
+			OX_RETURN_ERROR(cb(data->name, data->inode));
+		} else {
+			oxTrace("ox.fs.Directory.ls", "INVALID DIRECTORY ENTRY");
+		}
+	}
+	return {};
+}
+
+template<typename FileStore, typename InodeId_t>
+Result<typename FileStore::InodeId_t> Directory<FileStore, InodeId_t>::findEntry(StringViewCR name) const noexcept {
+	oxTrace("ox.fs.Directory.findEntry", name);
+	auto buff = m_fs.read(m_inodeId).template to<Buffer>();
+	if (!buff.valid()) {
+		oxTrace("ox.fs.Directory.findEntry.fail", "Could not findEntry directory buffer");
+		return ox::Error(2, "Could not findEntry directory buffer");
+	}
+	oxTracef("ox.fs.Directory.findEntry", "Found directory buffer, size: {}", buff.size());
+	for (auto i = buff->iterator(); i.valid(); i.next()) {
+		auto data = i->data();
+		if (data.valid()) {
+			oxTracef("ox.fs.Directory.findEntry", "Comparing \"{}\" to \"{}\"", name, data->name);
+			if (name == data->name) {
+				oxTracef("ox.fs.Directory.findEntry", "\"{}\" match found.", name);
+				return static_cast<InodeId_t>(data->inode);
+			}
+		} else {
+			oxTrace("ox.fs.Directory.findEntry", "INVALID DIRECTORY ENTRY");
+		}
+	}
+	oxTrace("ox.fs.Directory.findEntry.fail", "Entry not present");
+	return ox::Error(1, "Entry not present");
+}
+
+template<typename FileStore, typename InodeId_t>
+Result<typename FileStore::InodeId_t> Directory<FileStore, InodeId_t>::find(PathIterator path) const noexcept {
+	// determine if already exists
+	ox::StringView name;
+	OX_RETURN_ERROR(path.get(name));
+	OX_REQUIRE(v, findEntry(name));
+	// recurse if not at end of path
+	if (auto p = path.next(); p.valid()) {
+		Directory dir(m_fs, v);
+		return dir.find(p);
+	}
+	return v;
+}
+
+
+extern template class Directory<FileStore16, uint16_t>;
+extern template class Directory<FileStore32, uint32_t>;
+
+extern template struct DirectoryEntry<uint16_t>;
+extern template struct DirectoryEntry<uint32_t>;
+
+using Directory16 = Directory<FileStore16, uint16_t>;
+using Directory32 = Directory<FileStore32, uint32_t>;
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/include/ox/fs/filesystem/filelocation.hpp

@@ -0,0 +1,183 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/std.hpp>
+#include <ox/model/def.hpp>
+#include <ox/model/typenamecatcher.hpp>
+#include <ox/model/types.hpp>
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+enum class FileAddressType: int8_t {
+	None = -1,
+	Path,
+	ConstPath,
+	Inode,
+};
+
+class FileAddress {
+
+	template<typename T>
+	friend constexpr Error model(T *h, CommonPtrWith<FileAddress> auto *fa) noexcept;
+
+	public:
+		static constexpr auto TypeName = "net.drinkingtea.ox.FileAddress";
+		static constexpr auto TypeVersion = 1;
+
+		union Data {
+			static constexpr auto TypeName = "net.drinkingtea.ox.FileAddress.Data";
+			static constexpr auto TypeVersion = 1;
+			char *path = nullptr;
+			const char *constPath;
+			uint64_t inode;
+		};
+
+	protected:
+		FileAddressType m_type = FileAddressType::None;
+		Data m_data{};
+
+	public:
+		constexpr FileAddress() noexcept = default;
+
+		FileAddress(const FileAddress &other) noexcept;
+
+		FileAddress(FileAddress &&other) noexcept;
+
+		FileAddress(std::nullptr_t) noexcept;
+
+		FileAddress(uint64_t inode) noexcept;
+
+		explicit FileAddress(StringViewCR path) noexcept;
+
+		constexpr FileAddress(ox::StringLiteral path) noexcept;
+
+		constexpr ~FileAddress() noexcept;
+
+		FileAddress &operator=(const FileAddress &other) noexcept;
+
+		FileAddress &operator=(FileAddress &&other) noexcept;
+
+		bool operator==(const FileAddress &other) const noexcept;
+
+		bool operator==(StringViewCR path) const noexcept;
+
+		[[nodiscard]]
+		constexpr FileAddressType type() const noexcept {
+			switch (m_type) {
+				case FileAddressType::Path:
+				case FileAddressType::ConstPath:
+					return FileAddressType::Path;
+				default:
+					return m_type;
+			}
+		}
+
+		constexpr Result<uint64_t> getInode() const noexcept {
+			switch (m_type) {
+				case FileAddressType::Inode:
+					return m_data.inode;
+				default:
+					return ox::Error(1);
+			}
+		}
+
+		constexpr Result<ox::CStringView> getPath() const noexcept {
+			switch (m_type) {
+				case FileAddressType::Path:
+					return ox::CStringView(m_data.path);
+				case FileAddressType::ConstPath:
+					return ox::CStringView(m_data.constPath);
+				default:
+					return ox::Error(1);
+			}
+		}
+
+		explicit constexpr operator bool() const noexcept {
+			return m_type != FileAddressType::None;
+		}
+
+	private:
+		/**
+		 * Cleanup memory allocations.
+		 */
+		constexpr void cleanup() noexcept;
+
+		/**
+		 * Clears fields, but does not delete allocations.
+		 */
+		constexpr void clear() noexcept;
+
+};
+
+constexpr FileAddress::FileAddress(ox::StringLiteral path) noexcept {
+	m_data.constPath = path.c_str();
+	m_type = FileAddressType::ConstPath;
+}
+
+constexpr FileAddress::~FileAddress() noexcept {
+	cleanup();
+}
+
+constexpr void FileAddress::cleanup() noexcept {
+	if (m_type == FileAddressType::Path) {
+		safeDeleteArray(m_data.path);
+		clear();
+	}
+}
+
+constexpr void FileAddress::clear() noexcept {
+	m_data.path = nullptr;
+	m_type = FileAddressType::None;
+}
+
+template<>
+constexpr const char *getModelTypeName<FileAddress::Data>() noexcept {
+	return FileAddress::Data::TypeName;
+}
+
+template<>
+constexpr const char *getModelTypeName<FileAddress>() noexcept {
+	return FileAddress::TypeName;
+}
+
+template<typename T>
+constexpr Error model(T *h, CommonPtrWith<FileAddress::Data> auto *obj) noexcept {
+	OX_RETURN_ERROR(h->template setTypeInfo<FileAddress::Data>());
+	OX_RETURN_ERROR(h->fieldCString("path", &obj->path));
+	OX_RETURN_ERROR(h->fieldCString("constPath", &obj->path));
+	OX_RETURN_ERROR(h->field("inode", &obj->inode));
+	return {};
+}
+
+template<typename T>
+constexpr Error model(T *h, CommonPtrWith<FileAddress> auto *fa) noexcept {
+	OX_RETURN_ERROR(h->template setTypeInfo<FileAddress>());
+	if constexpr(T::opType() == OpType::Reflect) {
+		int8_t type = -1;
+		OX_RETURN_ERROR(h->field("type", &type));
+		OX_RETURN_ERROR(h->field("data", UnionView(&fa->m_data, type)));
+	} else if constexpr(T::opType() == OpType::Read) {
+		auto type = static_cast<int8_t>(fa->m_type);
+		OX_RETURN_ERROR(h->field("type", &type));
+		fa->m_type = static_cast<FileAddressType>(type);
+		OX_RETURN_ERROR(h->field("data", UnionView(&fa->m_data, static_cast<int>(fa->m_type))));
+	} else if constexpr(T::opType() == OpType::Write) {
+		auto const type = static_cast<int8_t>(fa->m_type);
+		OX_RETURN_ERROR(h->field("type", &type));
+		OX_RETURN_ERROR(h->field("data", UnionView(&fa->m_data, static_cast<int>(fa->m_type))));
+	}
+	return {};
+}
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/include/ox/fs/filesystem/filesystem.hpp

@@ -0,0 +1,553 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/buffer.hpp>
+#include <ox/std/span.hpp>
+
+#include <ox/fs/filestore/filestoretemplate.hpp>
+#include <ox/fs/filesystem/filelocation.hpp>
+#include <ox/fs/filesystem/types.hpp>
+
+#include "directory.hpp"
+
+namespace ox {
+
+namespace detail {
+inline void fsBuffFree(char *buff) noexcept {
+	safeDelete(buff);
+}
+}
+
+class FileSystem {
+
+	public:
+		virtual ~FileSystem() noexcept = default;
+
+		virtual Error mkdir(StringViewCR path, bool recursive) noexcept = 0;
+
+		/**
+		 * Moves an entry from one directory to another.
+		 * @param src the path to the file
+		 * @param dest the path of the destination directory
+		 */
+		virtual Error move(StringViewCR src, StringViewCR dest) noexcept = 0;
+
+		Error read(const FileAddress &addr, void *buffer, std::size_t size) noexcept;
+
+		Result<Buffer> read(FileAddress const &addr, size_t size) noexcept;
+
+		Result<Buffer> read(StringViewCR path, size_t size) noexcept;
+
+		Result<Buffer> read(const FileAddress &addr) noexcept;
+
+		Result<Buffer> read(StringViewCR path) noexcept;
+
+		Error read(StringViewCR path, void *buffer, std::size_t buffSize) noexcept {
+			return readFilePath(path, buffer, buffSize);
+		}
+
+		Error read(uint64_t inode, void *buffer, std::size_t buffSize) noexcept {
+			return readFileInode(inode, buffer, buffSize);
+		}
+
+		Error read(
+			FileAddress const &addr,
+			size_t readStart,
+			size_t readSize,
+			void *buffer,
+			size_t *size) noexcept;
+
+		/**
+		 *
+		 * @param path
+		 * @param readStart
+		 * @param readSize
+		 * @param buff
+		 * @return error or number of bytes read
+		 */
+		Result<size_t> read(
+			StringViewCR path, size_t readStart, size_t readSize, ox::Span<char> buff) noexcept;
+
+		virtual Result<Vector<String>> ls(StringViewCR dir) const noexcept = 0;
+
+		Error remove(StringViewCR path, bool recursive = false) noexcept {
+			return removePath(path, recursive);
+		}
+
+		virtual Error resize(uint64_t size, void *buffer) noexcept = 0;
+
+		Error write(StringViewCR path, const void *buffer, uint64_t size) noexcept {
+			return writeFilePath(path, buffer, size, FileType::NormalFile);
+		}
+
+		Error write(StringViewCR path, ox::SpanView<char> const&buff) noexcept {
+			return write(path, buff.data(), buff.size(), FileType::NormalFile);
+		}
+
+		Error write(uint64_t inode, const void *buffer, uint64_t size) noexcept {
+			return write(inode, buffer, size, FileType::NormalFile);
+		}
+
+		Error write(uint64_t inode, ox::SpanView<char> const&buff) noexcept {
+			return write(inode, buff.data(), buff.size(), FileType::NormalFile);
+		}
+
+		Error write(const FileAddress &addr, const void *buffer, uint64_t size, FileType fileType = FileType::NormalFile) noexcept;
+
+		Error write(StringViewCR path, const void *buffer, uint64_t size, FileType fileType) noexcept {
+			return writeFilePath(path, buffer, size, fileType);
+		}
+
+		Error write(uint64_t inode, const void *buffer, uint64_t size, FileType fileType) noexcept {
+			return writeFileInode(inode, buffer, size, fileType);
+		}
+
+		Result<FileStat> stat(uint64_t inode) const noexcept {
+			return statInode(inode);
+		}
+
+		Result<FileStat> stat(StringViewCR path) const noexcept {
+			return statPath(path);
+		}
+
+		Result<FileStat> stat(const FileAddress &addr) const noexcept;
+
+		[[nodiscard]]
+		bool exists(uint64_t inode) const noexcept {
+			return statInode(inode).ok();
+		}
+
+		[[nodiscard]]
+		bool exists(ox::StringView path) const noexcept {
+			return statPath(path).ok();
+		}
+
+		[[nodiscard]]
+		bool exists(FileAddress const&addr) const noexcept {
+			return stat(addr).ok();
+		}
+
+		[[nodiscard]]
+		virtual uint64_t spaceNeeded(uint64_t size) const noexcept = 0;
+
+		[[nodiscard]]
+		virtual Result<uint64_t> available() const noexcept = 0;
+
+		[[nodiscard]]
+		virtual Result<uint64_t> size() const noexcept = 0;
+
+		[[nodiscard]]
+		virtual char *buff() noexcept = 0;
+
+		virtual Error walk(Error(*cb)(uint8_t, uint64_t, uint64_t)) noexcept = 0;
+
+		[[nodiscard]]
+		virtual bool valid() const noexcept = 0;
+
+	protected:
+		virtual Result<FileStat> statInode(uint64_t inode) const noexcept = 0;
+
+		virtual Result<FileStat> statPath(StringViewCR path) const noexcept = 0;
+
+		virtual Error readFilePath(StringViewCR path, void *buffer, std::size_t buffSize) noexcept = 0;
+
+		virtual Error readFileInode(uint64_t inode, void *buffer, std::size_t size) noexcept = 0;
+
+		virtual Error readFilePathRange(
+			StringViewCR path, size_t readStart, size_t readSize, void *buffer, size_t *buffSize) noexcept = 0;
+
+		virtual Error readFileInodeRange(uint64_t inode, size_t readStart, size_t readSize, void *buffer, size_t *size) noexcept = 0;
+
+		virtual Error removePath(StringViewCR path, bool recursive) noexcept = 0;
+
+		virtual Error writeFilePath(StringViewCR path, const void *buffer, uint64_t size, FileType fileType) noexcept = 0;
+
+		virtual Error writeFileInode(uint64_t inode, const void *buffer, uint64_t size, FileType fileType) noexcept = 0;
+
+};
+
+class MemFS: public FileSystem {
+	public:
+		Result<const char*> directAccess(const FileAddress &addr) const noexcept;
+
+		Result<const char*> directAccess(StringViewCR path) const noexcept {
+			return directAccessPath(path);
+		}
+
+		Result<const char*> directAccess(uint64_t inode) const noexcept {
+			return directAccessInode(inode);
+		}
+
+	protected:
+		virtual Result<const char*> directAccessPath(StringViewCR path) const noexcept = 0;
+
+		virtual Result<const char*> directAccessInode(uint64_t inode) const noexcept = 0;
+};
+
+/**
+ * FileSystemTemplate used to create file system that wraps around a FileStore,
+ * taking an inode size and a directory type as parameters.
+ *
+ * Note: Directory parameter must have a default constructor.
+ */
+template<typename FileStore, typename Directory>
+class FileSystemTemplate: public MemFS {
+	private:
+		static constexpr auto InodeFsData = 2;
+
+		struct OX_PACKED FileSystemData {
+			LittleEndian<typename FileStore::InodeId_t> rootDirInode;
+		};
+
+		FileStore m_fs;
+		void(*m_freeBuffer)(char*) = nullptr;
+
+	public:
+		FileSystemTemplate() noexcept = default;
+
+		FileSystemTemplate(void *buffer, uint64_t bufferSize, void(*freeBuffer)(char*) = detail::fsBuffFree) noexcept;
+
+		explicit FileSystemTemplate(ox::Buffer &buffer) noexcept;
+
+		explicit FileSystemTemplate(FileStore fs) noexcept;
+
+		~FileSystemTemplate() noexcept override;
+
+		static Error format(void *buff, uint64_t buffSize) noexcept;
+
+		Error mkdir(StringViewCR path, bool recursive) noexcept override;
+
+		Error move(StringViewCR src, StringViewCR dest) noexcept override;
+
+		Error readFilePath(StringViewCR path, void *buffer, std::size_t buffSize) noexcept override;
+
+		Result<const char*> directAccessPath(StringViewCR) const noexcept override;
+
+		Error readFileInode(uint64_t inode, void *buffer, std::size_t size) noexcept override;
+
+		Error readFileInodeRange(uint64_t inode, std::size_t readStart, std::size_t readSize, void *buffer, std::size_t *size) noexcept override;
+
+		Error readFilePathRange(
+			StringViewCR path, size_t readStart, size_t readSize, void *buffer, size_t *buffSize) noexcept override;
+
+		Error removePath(StringViewCR path, bool recursive) noexcept override;
+
+		Result<const char*> directAccessInode(uint64_t) const noexcept override;
+
+		Result<Vector<String>> ls(StringViewCR dir) const noexcept override;
+
+		template<typename F>
+		Error ls(StringViewCR path, F cb) const;
+
+		/**
+		 * Resizes FileSystem to minimum possible size.
+		 */
+		Error resize() noexcept;
+
+		Error resize(uint64_t size, void *buffer) noexcept override;
+
+		Error writeFilePath(StringViewCR path, const void *buffer, uint64_t size, FileType fileType) noexcept override;
+
+		Error writeFileInode(uint64_t inode, const void *buffer, uint64_t size, FileType fileType) noexcept override;
+
+		Result<FileStat> statInode(uint64_t inode) const noexcept override;
+
+		Result<FileStat> statPath(StringViewCR path) const noexcept override;
+
+		[[nodiscard]]
+		uint64_t spaceNeeded(uint64_t size) const noexcept override;
+
+		Result<uint64_t> available() const noexcept override;
+
+		Result<uint64_t> size() const noexcept override;
+
+		char *buff() noexcept override;
+
+		Error walk(Error(*cb)(uint8_t, uint64_t, uint64_t)) noexcept override;
+
+		[[nodiscard]]
+		bool valid() const noexcept override;
+
+	private:
+		Result<FileSystemData> fileSystemData() const noexcept;
+
+		/**
+		 * Finds the inode ID at the given path.
+		 */
+		Result<uint64_t> find(StringViewCR path) const noexcept;
+
+		Result<Directory> rootDir() const noexcept;
+
+};
+
+template<typename FileStore, typename Directory>
+FileSystemTemplate<FileStore, Directory>::FileSystemTemplate(FileStore fs) noexcept {
+	m_fs = fs;
+}
+
+template<typename FileStore, typename Directory>
+FileSystemTemplate<FileStore, Directory>::FileSystemTemplate(ox::Buffer &buffer) noexcept:
+		m_fs(buffer.data(), static_cast<std::size_t>(buffer.size())) {
+}
+
+template<typename FileStore, typename Directory>
+FileSystemTemplate<FileStore, Directory>::FileSystemTemplate(void *buffer, uint64_t bufferSize, void(*freeBuffer)(char*)) noexcept:
+	m_fs(buffer, static_cast<std::size_t>(bufferSize)),
+	m_freeBuffer(freeBuffer) {
+}
+
+template<typename FileStore, typename Directory>
+FileSystemTemplate<FileStore, Directory>::~FileSystemTemplate() noexcept {
+	if (m_freeBuffer && m_fs.buff()) {
+		m_freeBuffer(m_fs.buff());
+	}
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::format(void *buff, uint64_t buffSize) noexcept {
+	OX_RETURN_ERROR(FileStore::format(buff, static_cast<size_t>(buffSize)));
+	FileStore fs(buff, static_cast<size_t>(buffSize));
+
+	constexpr auto rootDirInode = MaxValue<typename FileStore::InodeId_t> / 2;
+	Directory rootDir(fs, rootDirInode);
+	OX_RETURN_ERROR(rootDir.init());
+
+	FileSystemData fd;
+	fd.rootDirInode = rootDirInode;
+	oxTracef("ox.fs.FileSystemTemplate.format", "rootDirInode: {}", fd.rootDirInode.get());
+	OX_RETURN_ERROR(fs.write(InodeFsData, &fd, sizeof(fd)));
+
+	if (!fs.read(fd.rootDirInode).valid()) {
+		oxTrace("ox.fs.FileSystemTemplate.format.error", "FileSystemTemplate::format did not correctly create root directory");
+		return ox::Error(1);
+	}
+
+	return {};
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::mkdir(StringViewCR path, bool recursive) noexcept {
+	oxTracef("ox.fs.FileSystemTemplate.mkdir", "path: {}, recursive: {}", path, recursive);
+	OX_REQUIRE_M(rootDir, this->rootDir());
+	return rootDir.mkdir(path, recursive);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::move(StringViewCR src, StringViewCR dest) noexcept {
+	OX_REQUIRE(fd, fileSystemData());
+	Directory rootDir(m_fs, fd.rootDirInode);
+	OX_REQUIRE_M(inode, rootDir.find(src));
+	OX_RETURN_ERROR(rootDir.write(dest, inode));
+	OX_RETURN_ERROR(rootDir.remove(src));
+	return {};
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::readFilePath(StringViewCR path, void *buffer, std::size_t buffSize) noexcept {
+	oxTrace("ox.fs.FileSystemTemplate.readFilePath", path);
+	OX_REQUIRE(fd, fileSystemData());
+	Directory rootDir(m_fs, fd.rootDirInode);
+	OX_REQUIRE(s, stat(path));
+	if (s.size > buffSize) {
+		return ox::Error(1, "Buffer to small to load file");
+	}
+	return readFileInodeRange(s.inode, 0, static_cast<size_t>(s.size), buffer, &buffSize);
+}
+
+template<typename FileStore, typename Directory>
+Result<const char*> FileSystemTemplate<FileStore, Directory>::directAccessPath(StringViewCR path) const noexcept {
+	OX_REQUIRE(fd, fileSystemData());
+	Directory rootDir(m_fs, fd.rootDirInode);
+	OX_REQUIRE(inode, rootDir.find(path));
+	return directAccessInode(inode);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::readFileInode(uint64_t inode, void *buffer, std::size_t buffSize) noexcept {
+	oxTracef("ox.fs.FileSystemTemplate.readFileInode", "{}", inode);
+	OX_REQUIRE(s, stat(inode));
+	if (s.size > buffSize) {
+		return ox::Error(1, "Buffer to small to load file");
+	}
+	return readFileInodeRange(inode, 0, static_cast<size_t>(s.size), buffer, &buffSize);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::readFileInodeRange(uint64_t inode, std::size_t readStart, std::size_t readSize, void *buffer, std::size_t *size) noexcept {
+	return m_fs.read(inode, readStart, readSize, reinterpret_cast<uint8_t*>(buffer), size);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::readFilePathRange(
+	StringViewCR path, size_t readStart, size_t readSize, void *buffer, size_t *buffSize) noexcept {
+	OX_REQUIRE(s, stat(path));
+	return readFileInodeRange(s.inode, readStart, readSize, buffer, buffSize);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::removePath(StringViewCR path, bool recursive) noexcept {
+	OX_REQUIRE(fd, fileSystemData());
+	Directory rootDir(m_fs, fd.rootDirInode);
+	OX_REQUIRE(inode, rootDir.find(path));
+	OX_REQUIRE(st, statInode(inode));
+	if (st.fileType == FileType::NormalFile || recursive) {
+		if (auto err = rootDir.remove(path)) {
+			// removal failed, try putting the index back
+			oxLogError(rootDir.write(path, inode));
+			return err;
+		}
+	} else {
+		oxTrace("FileSystemTemplate.remove.fail", "Tried to remove directory without recursive setting.");
+		return ox::Error(1);
+	}
+	return {};
+}
+
+template<typename FileStore, typename Directory>
+Result<const char*> FileSystemTemplate<FileStore, Directory>::directAccessInode(uint64_t inode) const noexcept {
+	auto data = m_fs.read(inode);
+	if (!data.valid()) {
+		return ox::Error(1, "Data not valid");
+	}
+	return reinterpret_cast<char*>(data.get());
+}
+
+template<typename FileStore, typename Directory>
+Result<Vector<String>> FileSystemTemplate<FileStore, Directory>::ls(StringViewCR path) const noexcept {
+	Vector<String> out;
+	OX_RETURN_ERROR(ls(path, [&out](StringViewCR name, typename FileStore::InodeId_t) {
+		out.emplace_back(name);
+		return ox::Error{};
+	}));
+	return out;
+}
+
+template<typename FileStore, typename Directory>
+template<typename F>
+Error FileSystemTemplate<FileStore, Directory>::ls(StringViewCR path, F cb) const {
+	oxTracef("ox.fs.FileSystemTemplate.ls", "path: {}", path);
+	OX_REQUIRE(s, stat(path));
+	Directory dir(m_fs, s.inode);
+	return dir.ls(cb);
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::resize() noexcept {
+	return m_fs.resize();
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::resize(uint64_t size, void *buffer) noexcept {
+	OX_RETURN_ERROR(m_fs.resize(static_cast<size_t>(size), buffer));
+	return {};
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::writeFilePath(
+		StringViewCR path,
+		const void *buffer,
+		uint64_t size,
+		FileType fileType) noexcept {
+	oxTrace("ox.fs.FileSystemTemplate.writeFilePath", path);
+	auto [inode, err] = find(path);
+	if (err) {
+		OX_RETURN_ERROR(m_fs.generateInodeId().moveTo(inode));
+		OX_REQUIRE_M(rootDir, this->rootDir());
+		OX_RETURN_ERROR(rootDir.write(path, inode));
+	}
+	OX_RETURN_ERROR(writeFileInode(inode, buffer, size, fileType));
+	return {};
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::writeFileInode(uint64_t inode, const void *buffer, uint64_t size, FileType fileType) noexcept {
+	oxTrace("ox.fs.FileSystemTemplate.writeFileInode", ox::intToStr(inode));
+	return m_fs.write(inode, buffer, static_cast<size_t>(size), static_cast<uint8_t>(fileType));
+}
+
+template<typename FileStore, typename Directory>
+Result<FileStat> FileSystemTemplate<FileStore, Directory>::statInode(uint64_t inode) const noexcept {
+	OX_REQUIRE(s, m_fs.stat(inode));
+	FileStat out;
+	out.inode = s.inode;
+	out.links = s.links;
+	out.size = s.size;
+	out.fileType = static_cast<FileType>(s.fileType);
+	return out;
+}
+
+template<typename FileStore, typename Directory>
+Result<FileStat> FileSystemTemplate<FileStore, Directory>::statPath(StringViewCR path) const noexcept {
+	OX_REQUIRE(inode, find(path));
+	return stat(inode);
+}
+
+template<typename FileStore, typename Directory>
+uint64_t FileSystemTemplate<FileStore, Directory>::spaceNeeded(uint64_t size) const noexcept {
+	return m_fs.spaceNeeded(static_cast<size_t>(size));
+}
+
+template<typename FileStore, typename Directory>
+Result<uint64_t> FileSystemTemplate<FileStore, Directory>::available() const noexcept {
+	return m_fs.available();
+}
+
+template<typename FileStore, typename Directory>
+Result<uint64_t> FileSystemTemplate<FileStore, Directory>::size() const noexcept {
+	return m_fs.size();
+}
+
+template<typename FileStore, typename Directory>
+char *FileSystemTemplate<FileStore, Directory>::buff() noexcept {
+	return m_fs.buff();
+}
+
+template<typename FileStore, typename Directory>
+Error FileSystemTemplate<FileStore, Directory>::walk(Error(*cb)(uint8_t, uint64_t, uint64_t)) noexcept {
+	return m_fs.walk(cb);
+}
+
+template<typename FileStore, typename Directory>
+bool FileSystemTemplate<FileStore, Directory>::valid() const noexcept {
+	return m_fs.valid();
+}
+
+template<typename FileStore, typename Directory>
+Result<typename FileSystemTemplate<FileStore, Directory>::FileSystemData> FileSystemTemplate<FileStore, Directory>::fileSystemData() const noexcept {
+	FileSystemData fd;
+	OX_RETURN_ERROR(m_fs.read(InodeFsData, &fd, sizeof(fd)));
+	return fd;
+}
+
+template<typename FileStore, typename Directory>
+Result<uint64_t> FileSystemTemplate<FileStore, Directory>::find(StringViewCR path) const noexcept {
+	OX_REQUIRE(fd, fileSystemData());
+	// return root as a special case
+	if (path == "/") {
+		return static_cast<uint64_t>(fd.rootDirInode);
+	}
+	Directory rootDir(m_fs, fd.rootDirInode);
+	OX_REQUIRE(out, rootDir.find(path));
+	return static_cast<uint64_t>(out);
+}
+
+template<typename FileStore, typename Directory>
+Result<Directory> FileSystemTemplate<FileStore, Directory>::rootDir() const noexcept {
+	OX_REQUIRE(fd, fileSystemData());
+	return Directory(m_fs, fd.rootDirInode);
+}
+
+extern template class FileSystemTemplate<FileStore16, Directory16>;
+extern template class FileSystemTemplate<FileStore32, Directory32>;
+
+using FileSystem16 = FileSystemTemplate<FileStore16, Directory16>;
+using FileSystem32 = FileSystemTemplate<FileStore32, Directory32>;
+
+}

src/fs/include/ox/fs/filesystem/passthroughfs.hpp

@@ -0,0 +1,115 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#if __has_include(<filesystem>) && defined(OX_USE_STDLIB)
+
+#include <filesystem>
+
+#include <ox/std/bit.hpp>
+#include "filesystem.hpp"
+
+#define OX_HAS_PASSTHROUGHFS
+
+namespace ox {
+
+constexpr auto HasPassThroughFS = true;
+
+/**
+ *
+ */
+class PassThroughFS: public FileSystem {
+	private:
+		std::filesystem::path m_path;
+
+	public:
+		explicit PassThroughFS(StringViewCR dirPath);
+
+		~PassThroughFS() noexcept override;
+
+		[[nodiscard]]
+		String basePath() const noexcept;
+
+		Error mkdir(StringViewCR path, bool recursive) noexcept override;
+
+		Error move(StringViewCR src, StringViewCR dest) noexcept override;
+
+		Result<Vector<String>> ls(StringViewCR dir) const noexcept override;
+
+		template<typename F>
+		Error ls(StringViewCR dir, F cb) const noexcept;
+
+		Error resize(uint64_t size, void *buffer) noexcept override;
+
+		Result<FileStat> statInode(uint64_t inode) const noexcept override;
+
+		Result<FileStat> statPath(StringViewCR path) const noexcept override;
+
+		[[nodiscard]]
+		uint64_t spaceNeeded(uint64_t size) const noexcept override;
+
+		Result<uint64_t> available() const noexcept override;
+
+		Result<uint64_t> size() const noexcept override;
+
+		[[nodiscard]]
+		char *buff() noexcept override;
+
+		Error walk(Error(*cb)(uint8_t, uint64_t, uint64_t)) noexcept override;
+
+		[[nodiscard]]
+		bool valid() const noexcept override;
+
+	protected:
+		Error readFilePath(StringViewCR path, void *buffer, std::size_t buffSize) noexcept override;
+
+		Error readFileInode(uint64_t inode, void *buffer, std::size_t size) noexcept override;
+
+		Error readFilePathRange(
+			StringViewCR path, size_t readStart, size_t readSize, void *buffer, size_t *buffSize) noexcept override;
+
+		Error readFileInodeRange(uint64_t inode, std::size_t readStart, std::size_t readSize, void *buffer, std::size_t *size) noexcept override;
+
+		Error removePath(StringViewCR path, bool recursive) noexcept override;
+
+		Error writeFilePath(StringViewCR path, const void *buffer, uint64_t size, FileType fileType) noexcept override;
+
+		Error writeFileInode(uint64_t inode, const void *buffer, uint64_t size, FileType fileType) noexcept override;
+
+	private:
+		/**
+		 * Strips the leading slashes from a string.
+		 */
+		[[nodiscard]]
+		static std::string_view stripSlash(StringView path) noexcept;
+
+};
+
+template<typename F>
+Error PassThroughFS::ls(StringViewCR dir, F cb) const noexcept {
+	std::error_code ec;
+	const auto di = std::filesystem::directory_iterator(m_path / stripSlash(dir), ec);
+	OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: ls failed"));
+	for (auto &p : di) {
+		OX_RETURN_ERROR(cb(p.path().filename().c_str(), 0));
+	}
+	return {};
+}
+
+}
+
+#else
+
+namespace ox {
+
+constexpr auto HasPassThroughFS = false;
+
+}
+
+#endif

src/fs/include/ox/fs/filesystem/pathiterator.hpp

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/std.hpp>
+
+namespace ox {
+
+constexpr std::size_t MaxFileNameLength = 255;
+
+class PathIterator {
+	private:
+		const char *m_path = nullptr;
+		std::size_t m_iterator = 0;
+		std::size_t m_maxSize = 0;
+
+	public:
+		PathIterator(const char *path, std::size_t maxSize, std::size_t iterator = 0);
+
+		PathIterator(const char *path);
+
+		PathIterator(StringViewCR path);
+
+		Error dirPath(char *pathOut, std::size_t pathOutSize);
+
+		Error next(StringView &fileName);
+
+		Error get(StringView &fileName);
+
+		Result<std::size_t> nextSize() const;
+
+		[[nodiscard]]
+		bool hasNext() const;
+
+		[[nodiscard]]
+		bool valid() const;
+
+		[[nodiscard]]
+		PathIterator next() const;
+
+		[[nodiscard]]
+		const char *fullPath() const;
+
+};
+
+}

src/fs/include/ox/fs/filesystem/types.hpp

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/types.hpp>
+
+namespace ox {
+
+enum class FileType: uint8_t {
+	None = 0,
+	NormalFile = 1,
+	Directory  = 2
+};
+
+constexpr const char *toString(FileType t) noexcept {
+	switch (t) {
+		case FileType::NormalFile:
+			return "Normal File";
+		case FileType::Directory:
+			return "Directory";
+		default:
+			return "";
+	}
+}
+
+struct FileStat {
+	uint64_t inode = 0;
+	uint64_t links = 0;
+	uint64_t size = 0;
+	FileType fileType = FileType::None;
+};
+
+}

src/fs/include/ox/fs/fs.hpp

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "filestore/filestoretemplate.hpp"
+#include "filesystem/filelocation.hpp"
+#include "filesystem/filesystem.hpp"
+#include "filesystem/passthroughfs.hpp"
+#include "filesystem/directory.hpp"

src/fs/include/ox/fs/ptrarith/nodebuffer.hpp

@@ -0,0 +1,455 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/stddef.hpp>
+#include <ox/std/trace.hpp>
+
+#include "ptr.hpp"
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox::ptrarith {
+
+template<typename size_t, typename Item>
+class OX_PACKED NodeBuffer {
+
+	public:
+		struct OX_PACKED Header {
+			LittleEndian<size_t> size = sizeof(Header); // capacity
+			LittleEndian<size_t> bytesUsed = sizeof(Header);
+			LittleEndian<size_t> firstItem = 0;
+		};
+
+		using ItemPtr = Ptr<Item, size_t, sizeof(Header)>;
+
+		class Iterator {
+			private:
+				NodeBuffer *m_buffer = nullptr;
+				ItemPtr m_current;
+				size_t m_it = 0;
+
+			public:
+				Iterator(NodeBuffer *buffer, ItemPtr current) noexcept {
+					m_buffer = buffer;
+					m_current = current;
+					oxTrace("ox.ptrarith.Iterator.start") << current.offset();
+				}
+
+				operator const Item*() const noexcept {
+					return m_current;
+				}
+
+				ItemPtr ptr() noexcept {
+					return m_current;
+				}
+
+				[[nodiscard]]
+				Item *get() noexcept {
+					return m_current;
+				}
+
+				operator ItemPtr() noexcept {
+					return m_current;
+				}
+
+				operator Item*() noexcept {
+					return m_current;
+				}
+
+				const Item *operator->() const noexcept {
+					return m_current;
+				}
+
+				Item *operator->() noexcept {
+					return m_current;
+				}
+
+				[[nodiscard]]
+				bool valid() const noexcept {
+					return m_current.valid();
+				}
+
+				[[nodiscard]]
+				bool hasNext() noexcept {
+					if (m_current.valid()) {
+						oxTrace("ox.ptrarith.NodeBuffer.Iterator.hasNext.current") << m_current.offset();
+						auto next = m_buffer->next(m_current);
+						return next.valid() && m_buffer->firstItem() != next;
+					}
+					return false;
+				}
+
+				void next() noexcept {
+					oxTrace("ox.ptrarith.NodeBuffer.Iterator.next") << m_it++;
+					if (hasNext()) {
+						m_current = m_buffer->next(m_current);
+					} else {
+						m_current = nullptr;
+					}
+				}
+		};
+
+		Header m_header;
+
+	public:
+		NodeBuffer(const NodeBuffer &other, std::size_t size) noexcept;
+
+		explicit NodeBuffer(std::size_t size) noexcept;
+
+		[[nodiscard]]
+		const Iterator iterator() const noexcept;
+
+		[[nodiscard]]
+		Iterator iterator() noexcept;
+
+		ItemPtr firstItem() noexcept;
+
+		ItemPtr lastItem() noexcept;
+
+		/**
+		 * @return the data section of the given item
+		 */
+		template<typename T>
+		Ptr<T, size_t, sizeof(Item)> dataOf(ItemPtr) noexcept;
+
+		ItemPtr prev(Item *item) noexcept;
+
+		ItemPtr next(Item *item) noexcept;
+
+		/**
+		 * Like pointer but omits checks that assume the memory at the offset has
+		 * already been initialed as an Item.
+		 */
+		ItemPtr uninitializedPtr(size_t offset) noexcept;
+
+		ItemPtr ptr(size_t offset) noexcept;
+
+		Result<ItemPtr> malloc(std::size_t size) noexcept;
+
+		Error free(ItemPtr item) noexcept;
+
+		[[nodiscard]]
+		bool valid(size_t maxSize) const noexcept;
+
+		/**
+		 * Set size, capacity.
+		 */
+		Error setSize(std::size_t size) noexcept;
+
+		/**
+		 * Get size, capacity.
+		 * @return capacity
+		 */
+		[[nodiscard]]
+		constexpr size_t size() const noexcept;
+
+		/**
+		 * @return the bytes still available in this NodeBuffer
+		 */
+		[[nodiscard]]
+		size_t available() const noexcept;
+
+		/**
+		 * @return the actual number a bytes need to store the given number of
+		 * bytes
+		 */
+		[[nodiscard]]
+		static size_t spaceNeeded(std::size_t size) noexcept;
+
+		template<typename F>
+		Error compact(F cb = [](uint64_t, ItemPtr) {}) noexcept;
+
+	private:
+		[[nodiscard]]
+		uint8_t *data() noexcept;
+
+};
+
+template<typename size_t, typename Item>
+NodeBuffer<size_t, Item>::NodeBuffer(std::size_t size) noexcept {
+	m_header.size = static_cast<size_t>(size);
+	ox::memset(this + 1, 0, size - sizeof(*this));
+	oxTracef("ox.ptrarith.NodeBuffer.constructor", "{}", m_header.firstItem.get());
+}
+
+template<typename size_t, typename Item>
+NodeBuffer<size_t, Item>::NodeBuffer(const NodeBuffer &other, std::size_t size) noexcept {
+	oxTracef("ox.ptrarith.NodeBuffer.copy", "other.m_header.firstItem: {}", other.m_header.firstItem.get());
+	ox::memset(this + 1, 0, size - sizeof(*this));
+	ox::memcpy(this, &other, size);
+}
+
+template<typename size_t, typename Item>
+const typename NodeBuffer<size_t, Item>::Iterator NodeBuffer<size_t, Item>::iterator() const noexcept {
+	return Iterator(this, firstItem());
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::Iterator NodeBuffer<size_t, Item>::iterator() noexcept {
+	oxTracef("ox.ptrarith.NodeBuffer.iterator.size", "{}", m_header.size.get());
+	return Iterator(this, firstItem());
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::firstItem() noexcept {
+	//oxTrace("ox::ptrarith::NodeBuffer::firstItem") << m_header.firstItem;
+	return ptr(m_header.firstItem);
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::lastItem() noexcept {
+	auto first = ptr(m_header.firstItem);
+	if (first.valid()) {
+		return prev(first);
+	}
+	return nullptr;
+}
+
+template<typename size_t, typename Item>
+template<typename T>
+Ptr<T, size_t, sizeof(Item)> NodeBuffer<size_t, Item>::dataOf(ItemPtr ip) noexcept {
+	auto out = ip.template subPtr<T>(sizeof(Item));
+	oxAssert(out.size() == ip.size() - sizeof(Item), "Sub Ptr has invalid size.");
+	return out;
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::prev(Item *item) noexcept {
+	return ptr(item->prev);
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::next(Item *item) noexcept {
+	return ptr(item->next);
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::uninitializedPtr(size_t itemOffset) noexcept {
+	// make sure this can be read as an Item, and then use Item::size for the size
+	std::size_t itemSpace = m_header.size - itemOffset;
+	if (itemOffset >= sizeof(Header) &&
+	    itemOffset + itemSpace <= size() &&
+	    itemSpace >= sizeof(Item)) {
+		return ItemPtr(this, m_header.size, itemOffset, itemSpace);
+	} else {
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemOffset:" << itemOffset;
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemOffset >= sizeof(Header):" << (itemOffset >= sizeof(Header));
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemSpace >= sizeof(Item):" << (itemSpace >= sizeof(Item));
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemSpace >= item->fullSize():" << (itemSpace >= item->fullSize());
+		return ItemPtr(this, m_header.size, 0, 0);
+	}
+}
+
+template<typename size_t, typename Item>
+typename NodeBuffer<size_t, Item>::ItemPtr NodeBuffer<size_t, Item>::ptr(size_t itemOffset) noexcept {
+	// make sure this can be read as an Item, and then use Item::size for the size
+	std::size_t itemSpace = m_header.size - itemOffset;
+	auto item = reinterpret_cast<Item*>(reinterpret_cast<uint8_t*>(this) + itemOffset);
+	if (itemOffset >= sizeof(Header) &&
+	    itemOffset + itemSpace <= size() &&
+	    itemSpace >= sizeof(Item) &&
+	    itemSpace >= item->fullSize()) {
+		return ItemPtr(this, m_header.size, itemOffset, item->fullSize());
+	} else {
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemOffset:" << itemOffset;
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemOffset >= sizeof(Header):" << (itemOffset >= sizeof(Header));
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemSpace >= sizeof(Item):" << (itemSpace >= sizeof(Item));
+		//oxTrace("ox::ptrarith::NodeBuffer::ptr::null") << "itemSpace >= item->fullSize():" << (itemSpace >= item->fullSize());
+		return ItemPtr(this, m_header.size, 0, 0);
+	}
+}
+
+template<typename size_t, typename Item>
+Result<typename NodeBuffer<size_t, Item>::ItemPtr> NodeBuffer<size_t, Item>::malloc(std::size_t size) noexcept {
+	const auto sz = static_cast<std::size_t>(size);
+	oxTracef("ox.ptrarith.NodeBuffer.malloc", "Size: {}", sz);
+	size_t fullSize = static_cast<size_t>(sz + sizeof(Item));
+	if (m_header.size - m_header.bytesUsed >= fullSize) {
+		auto last = lastItem();
+		size_t addr;
+		if (last.valid()) {
+			addr = last.offset() + last.size();
+		} else {
+			// there is no first item, so this must be the first item
+			if (!m_header.firstItem) {
+				oxTrace("ox.ptrarith.NodeBuffer.malloc", "No first item, initializing.");
+				m_header.firstItem = static_cast<size_t>(sizeof(m_header));
+				addr = m_header.firstItem;
+			} else {
+				oxTrace("ox.ptrarith.NodeBuffer.malloc.fail", "NodeBuffer is in invalid state.");
+				return ox::Error(1, "NodeBuffer is in invalid state.");
+			}
+		}
+		oxTracef("ox.ptrarith.NodeBuffer.malloc", "buffer size: {}; addr: {}; fullSize: {}", m_header.size.get(), addr, fullSize);
+		auto out = ItemPtr(this, m_header.size, addr, fullSize);
+		if (!out.valid()) {
+			oxTrace("ox.ptrarith.NodeBuffer.malloc.fail", "Unknown");
+			return ox::Error(1, "NodeBuffer::malloc: unknown failure");
+		}
+		ox::memset(out, 0, fullSize);
+		new (out) Item;
+		out->setSize(sz);
+
+		auto first = firstItem();
+		auto oldLast = last;
+		out->next = first.offset();
+		if (first.valid()) {
+			first->prev = out.offset();
+		} else {
+			oxTrace("ox.ptrarith.NodeBuffer.malloc.fail", "NodeBuffer malloc failed due to invalid first element pointer.");
+			return ox::Error(1, "NodeBuffer malloc failed due to invalid first element pointer.");
+		}
+
+		if (oldLast.valid()) {
+			out->prev = oldLast.offset();
+			oldLast->next = out.offset();
+		} else { // check to see if this is the first allocation
+			if (out.offset() != first.offset()) {
+				// if this is not the first allocation, there should be an oldLast
+				oxTrace("ox.ptrarith.NodeBuffer.malloc.fail", "NodeBuffer malloc failed due to invalid last element pointer.");
+				return ox::Error(1, "NodeBuffer malloc failed due to invalid last element pointer.");
+			}
+			out->prev = out.offset();
+		}
+		m_header.bytesUsed += out.size();
+		oxTracef("ox.ptrarith.NodeBuffer.malloc", "Offset: {}", out.offset());
+		return out;
+	}
+	oxTracef("ox.ptrarith.NodeBuffer.malloc.fail", "Insufficient space: {} needed, {} available", fullSize, available());
+	return ox::Error(1);
+}
+
+template<typename size_t, typename Item>
+Error NodeBuffer<size_t, Item>::free(ItemPtr item) noexcept {
+	oxTracef("ox.ptrarith.NodeBuffer.free", "offset: {}", item.offset());
+	auto prev = this->prev(item);
+	auto next = this->next(item);
+	if (prev.valid() && next.valid()) {
+		if (next != item) {
+			prev->next = next;
+			next->prev = prev;
+			if (item.offset() == m_header.firstItem) {
+				m_header.firstItem = next;
+			}
+		} else {
+			// only one item, null out first
+			oxTrace("ox.ptrarith.NodeBuffer.free", "Nulling out firstItem.");
+			m_header.firstItem = 0;
+		}
+	} else {
+		if (!prev.valid()) {
+			oxTracef("ox.ptrarith.NodeBuffer.free.fail", "NodeBuffer free failed due to invalid prev element pointer: {}", prev.offset());
+			return ox::Error(1);
+		}
+		if (!next.valid()) {
+			oxTracef("ox.ptrarith.NodeBuffer.free.fail", "NodeBuffer free failed due to invalid next element pointer: {}", next.offset());
+			return ox::Error(1);
+		}
+	}
+	m_header.bytesUsed -= item.size();
+	return {};
+}
+
+template<typename size_t, typename Item>
+Error NodeBuffer<size_t, Item>::setSize(std::size_t size) noexcept {
+	oxTracef("ox.ptrarith.NodeBuffer.setSize", "{} to {}", m_header.size.get(), size);
+	auto last = lastItem();
+	auto end = last.valid() ? last.end() : sizeof(m_header);
+	oxTracef("ox.ptrarith.NodeBuffer.setSize", "end: {}", end);
+	if (end > size) {
+		// resizing to less than buffer size
+		return ox::Error(1);
+	} else {
+		m_header.size = static_cast<size_t>(size);
+		auto data = reinterpret_cast<uint8_t*>(this) + end;
+		ox::memset(data, 0, size - end);
+		return {};
+	}
+}
+
+template<typename size_t, typename Item>
+constexpr size_t NodeBuffer<size_t, Item>::size() const noexcept {
+	return m_header.size;
+}
+
+template<typename size_t, typename Item>
+bool NodeBuffer<size_t, Item>::valid(size_t maxSize) const noexcept {
+	return m_header.size <= maxSize;
+}
+
+template<typename size_t, typename Item>
+size_t NodeBuffer<size_t, Item>::available() const noexcept {
+	return m_header.size - m_header.bytesUsed;
+}
+
+template<typename size_t, typename Item>
+size_t NodeBuffer<size_t, Item>::spaceNeeded(std::size_t size) noexcept {
+	return static_cast<size_t>(sizeof(Item) + size);
+}
+
+template<typename size_t, typename Item>
+template<typename F>
+Error NodeBuffer<size_t, Item>::compact(F cb) noexcept {
+	auto src = firstItem();
+	auto dest = ptr(sizeof(*this));
+	while (dest.offset() <= src.offset()) {
+		if (!src.valid()) {
+			return ox::Error(1);
+		}
+		if (!dest.valid()) {
+			return ox::Error(2);
+		}
+		// move node
+		ox::memcpy(dest, src, src->fullSize());
+		OX_RETURN_ERROR(cb(src, dest));
+		// update surrounding nodes
+		auto prev = ptr(dest->prev);
+		if (prev.valid()) {
+			prev->next = dest;
+		}
+		auto next = ptr(dest->next);
+		if (next.valid()) {
+			next->prev = dest;
+		}
+		// update iterators
+		src = ptr(dest->next);
+		dest = uninitializedPtr(dest.offset() + dest->fullSize());
+	}
+	return {};
+}
+
+template<typename size_t, typename Item>
+uint8_t *NodeBuffer<size_t, Item>::data() noexcept {
+	return reinterpret_cast<uint8_t*>(ptr(sizeof(*this)).get());
+}
+
+
+template<typename size_t>
+struct OX_PACKED Item {
+	public:
+		LittleEndian<size_t> prev = 0;
+		LittleEndian<size_t> next = 0;
+
+	private:
+		LittleEndian<size_t> m_size = sizeof(Item);
+
+	public:
+		size_t size() const {
+			return m_size;
+		}
+
+		void setSize(std::size_t size) {
+			m_size = static_cast<size_t>(size);
+		}
+};
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/include/ox/fs/ptrarith/ptr.hpp

@@ -0,0 +1,262 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/std.hpp>
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox::ptrarith {
+
+template<typename T, typename size_t, size_t minOffset = 1>
+class [[nodiscard]] Ptr {
+
+	private:
+		uint8_t *m_dataStart = nullptr;
+		size_t m_dataSize = 0;
+		size_t m_itemOffset = 0;
+		size_t m_itemSize = 0;
+		// this should be removed later on, but the excessive validation is
+		// desirable during during heavy development
+		mutable uint8_t m_validated = false;
+
+	public:
+		constexpr Ptr() noexcept = default;
+
+		constexpr Ptr(std::nullptr_t) noexcept;
+
+		constexpr Ptr(
+			void *pDataStart,
+			std::size_t pDataSize,
+			std::size_t pItemStart,
+			std::size_t pItemSize = sizeof(T),
+			std::size_t pItemTypeSize = sizeof(T),
+			bool pPrevalidated = false) noexcept;
+
+		[[nodiscard]]
+		constexpr bool valid() const noexcept;
+
+		constexpr size_t size() const noexcept;
+
+		constexpr size_t offset() const noexcept;
+
+		constexpr size_t end() noexcept;
+
+		constexpr const T *get() const noexcept;
+
+		constexpr T *get() noexcept;
+
+		constexpr const T *operator->() const noexcept;
+
+		constexpr T *operator->() noexcept;
+
+		constexpr operator const T*() const noexcept;
+
+		constexpr operator T*() noexcept;
+
+		constexpr const T &operator*() const noexcept;
+
+		constexpr T &operator*() noexcept;
+
+		constexpr operator size_t() const noexcept;
+
+		constexpr bool operator==(const Ptr<T, size_t, minOffset> &other) const noexcept;
+
+		constexpr bool operator!=(const Ptr<T, size_t, minOffset> &other) const noexcept;
+
+		template<typename SubT>
+		constexpr const Ptr<SubT, size_t, sizeof(T)> subPtr(size_t offset, size_t size) const noexcept;
+
+		template<typename SubT>
+		constexpr const Ptr<SubT, size_t, sizeof(T)> subPtr(size_t offset) const noexcept;
+
+		template<typename SubT>
+		constexpr Ptr<SubT, size_t, sizeof(T)> subPtr(size_t offset, size_t size) noexcept;
+
+		template<typename SubT>
+		constexpr Ptr<SubT, size_t, sizeof(T)> subPtr(size_t offset) noexcept;
+
+		template<typename SubT>
+		constexpr const Ptr<SubT, size_t, minOffset> to() const noexcept;
+
+		constexpr Result<Ptr<T, size_t, minOffset>> validate() const noexcept;
+
+};
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Ptr<T, size_t, minOffset>::Ptr(std::nullptr_t) noexcept {
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Ptr<T, size_t, minOffset>::Ptr(
+		void *pDataStart,
+		std::size_t pDataSize,
+		std::size_t pItemStart,
+		std::size_t pItemSize,
+		std::size_t pItemTypeSize,
+		bool pPrevalidated) noexcept {
+	const auto dataSize = static_cast<size_t>(pDataSize);
+	const auto itemStart = static_cast<size_t>(pItemStart);
+	const auto itemSize = static_cast<size_t>(pItemSize);
+	const auto itemTypeSize = static_cast<size_t>(pItemTypeSize);
+	// do some sanity checks before assuming this is valid
+	if (itemSize >= itemTypeSize &&
+	    pDataStart &&
+	    itemStart >= minOffset &&
+	    itemStart + itemSize <= dataSize) {
+		m_dataStart = reinterpret_cast<uint8_t*>(pDataStart);
+		m_dataSize = dataSize;
+		m_itemOffset = itemStart;
+		m_itemSize = itemSize;
+		m_validated = pPrevalidated;
+	}
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr bool Ptr<T, size_t, minOffset>::valid() const noexcept {
+	m_validated = m_dataStart != nullptr;
+	return m_validated;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr size_t Ptr<T, size_t, minOffset>::size() const noexcept {
+	return m_itemSize;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr size_t Ptr<T, size_t, minOffset>::offset() const noexcept {
+	return m_itemOffset;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr size_t Ptr<T, size_t, minOffset>::end() noexcept {
+	return m_itemOffset + m_itemSize;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr const T *Ptr<T, size_t, minOffset>::get() const noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::get())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::get())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr T *Ptr<T, size_t, minOffset>::get() noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::get())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::get())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr const T *Ptr<T, size_t, minOffset>::operator->() const noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::operator->())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::operator->())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr T *Ptr<T, size_t, minOffset>::operator->() noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::operator->())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::operator->())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Ptr<T, size_t, minOffset>::operator const T*() const noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::operator const T*())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::operator const T*())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Ptr<T, size_t, minOffset>::operator T*() noexcept {
+	oxAssert(m_validated, "Unvalidated pointer access. (ox::fs::Ptr::operator T*())");
+	oxAssert(valid(), "Invalid pointer access. (ox::fs::Ptr::operator T*())");
+	return reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr const T &Ptr<T, size_t, minOffset>::operator*() const noexcept {
+	oxAssert(m_validated, "Unvalidated pointer dereference. (ox::fs::Ptr::operator*())");
+	oxAssert(valid(), "Invalid pointer dereference. (ox::fs::Ptr::operator*())");
+	return *reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr T &Ptr<T, size_t, minOffset>::operator*() noexcept {
+	oxAssert(m_validated, "Unvalidated pointer dereference. (ox::fs::Ptr::operator*())");
+	oxAssert(valid(), "Invalid pointer dereference. (ox::fs::Ptr::operator*())");
+	return *reinterpret_cast<T*>(m_dataStart + m_itemOffset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Ptr<T, size_t, minOffset>::operator size_t() const noexcept {
+	if (m_dataStart && m_itemOffset) {
+		return m_itemOffset;
+	}
+	return 0;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr bool Ptr<T, size_t, minOffset>::operator==(const Ptr<T, size_t, minOffset> &other) const noexcept {
+	return m_dataStart == other.m_dataStart &&
+	       m_itemOffset == other.m_itemOffset &&
+	       m_itemSize == other.m_itemSize;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr bool Ptr<T, size_t, minOffset>::operator!=(const Ptr<T, size_t, minOffset> &other) const noexcept {
+	return m_dataStart != other.m_dataStart ||
+	       m_itemOffset != other.m_itemOffset ||
+	       m_itemSize != other.m_itemSize;
+}
+
+template<typename T, typename size_t, size_t minOffset>
+template<typename SubT>
+constexpr const Ptr<SubT, size_t, sizeof(T)> Ptr<T, size_t, minOffset>::subPtr(size_t offset, size_t size) const noexcept {
+	return Ptr<SubT, size_t, sizeof(T)>(get(), this->size(), offset, size);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+template<typename SubT>
+constexpr const Ptr<SubT, size_t, sizeof(T)> Ptr<T, size_t, minOffset>::subPtr(size_t offset) const noexcept {
+	oxTracef("ox.ptrarith.Ptr.subPtr", "{} {} {} {} {}", m_itemOffset, this->size(), offset, m_itemSize, (m_itemSize - offset));
+	return subPtr<SubT>(offset, m_itemSize - offset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+template<typename SubT>
+constexpr Ptr<SubT, size_t, sizeof(T)> Ptr<T, size_t, minOffset>::subPtr(size_t offset, size_t size) noexcept {
+	return Ptr<SubT, size_t, sizeof(T)>(get(), this->size(), offset, size);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+template<typename SubT>
+constexpr Ptr<SubT, size_t, sizeof(T)> Ptr<T, size_t, minOffset>::subPtr(size_t offset) noexcept {
+	oxTracef("ox.ptrarith.Ptr.subPtr", "{} {} {} {} {}", m_itemOffset, this->size(), offset, m_itemSize, (m_itemSize - offset));
+	return subPtr<SubT>(offset, m_itemSize - offset);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+template<typename SubT>
+constexpr const Ptr<SubT, size_t, minOffset> Ptr<T, size_t, minOffset>::to() const noexcept {
+	return Ptr<SubT, size_t, minOffset>(m_dataStart, m_dataSize, m_itemOffset, m_itemSize);
+}
+
+template<typename T, typename size_t, size_t minOffset>
+constexpr Result<Ptr<T, size_t, minOffset>> Ptr<T, size_t, minOffset>::validate() const noexcept {
+	 if (valid()) {
+	 	return *this;
+	 }
+	 return ox::Error(1);
+}
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/src/filestore/filestoretemplate.cpp

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/fs/filestore/filestoretemplate.hpp>
+
+namespace ox {
+
+template class FileStoreTemplate<uint16_t>;
+template class FileStoreTemplate<uint32_t>;
+
+}

src/fs/src/filesystem/directory.cpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/fs/filesystem/directory.hpp>
+
+namespace ox {
+
+template class Directory<FileStore16, uint16_t>;
+template class Directory<FileStore32, uint32_t>;
+
+template struct DirectoryEntry<uint16_t>;
+template struct DirectoryEntry<uint32_t>;
+
+}

src/fs/src/filesystem/filelocation.cpp

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/model/modelops.hpp>
+
+#include <ox/fs/filesystem/filelocation.hpp>
+
+namespace ox {
+
+FileAddress::FileAddress(const FileAddress &other) noexcept {
+	operator=(other);
+}
+
+FileAddress::FileAddress(FileAddress &&other) noexcept {
+	operator=(std::move(other));
+}
+
+FileAddress::FileAddress(std::nullptr_t) noexcept {
+}
+
+FileAddress::FileAddress(uint64_t inode) noexcept {
+	m_data.inode = inode;
+	m_type = FileAddressType::Inode;
+}
+
+FileAddress::FileAddress(ox::StringViewCR path) noexcept {
+	auto pathSize = path.bytes();
+	m_data.path = new char[pathSize + 1];
+	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+	memcpy(m_data.path, path.data(), pathSize);
+	m_data.path[pathSize] = 0;
+	OX_ALLOW_UNSAFE_BUFFERS_END
+	m_type = FileAddressType::Path;
+}
+
+FileAddress &FileAddress::operator=(const FileAddress &other) noexcept {
+	if (this == &other) {
+		return *this;
+	}
+	cleanup();
+	m_type = other.m_type;
+	switch (m_type) {
+		case FileAddressType::Path:
+		{
+			if (other.m_data.path) {
+				OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+				auto strSize = ox::strlen(other.m_data.path) + 1;
+				m_data.path = new char[strSize];
+				ox::memcpy(m_data.path, other.m_data.path, strSize);
+				OX_ALLOW_UNSAFE_BUFFERS_END
+			} else {
+				m_data.constPath = "";
+				m_type = FileAddressType::ConstPath;
+			}
+			break;
+		}
+		case FileAddressType::ConstPath:
+		case FileAddressType::Inode:
+			m_data = other.m_data;
+			break;
+		case FileAddressType::None:
+			break;
+	}
+	return *this;
+}
+
+FileAddress &FileAddress::operator=(FileAddress &&other) noexcept {
+	if (this == &other) {
+		return *this;
+	}
+	cleanup();
+	m_type = other.m_type;
+	switch (m_type) {
+		case FileAddressType::Path:
+		{
+			m_data.path = other.m_data.path;
+			break;
+		}
+		case FileAddressType::ConstPath:
+		case FileAddressType::Inode:
+			m_data = other.m_data;
+			break;
+		case FileAddressType::None:
+			break;
+	}
+	other.clear();
+	return *this;
+}
+
+bool FileAddress::operator==(FileAddress const&other) const noexcept {
+	if (m_type != other.m_type) {
+		auto const aIsPath =
+				m_type == FileAddressType::Path || m_type == FileAddressType::ConstPath;
+		auto const bIsPath =
+				other.m_type == FileAddressType::Path || other.m_type == FileAddressType::ConstPath;
+		if (!(aIsPath && bIsPath)) {
+			return false;
+		}
+	}
+	switch (m_type) {
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path: {
+			auto const a = getPath();
+			auto const b = other.getPath();
+			return (other.m_type == FileAddressType::ConstPath || other.m_type == FileAddressType::Path)
+			    && (a.value == b.value);
+		}
+		case FileAddressType::Inode:
+			return m_data.inode == other.m_data.inode;
+		case FileAddressType::None:
+			return true;
+	}
+	return true;
+}
+
+bool FileAddress::operator==(StringViewCR path) const noexcept {
+	auto [p, err] = getPath();
+	if (err) {
+		return false;
+	}
+	return path == p;
+}
+
+}

src/fs/src/filesystem/filesystem.cpp

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/error.hpp>
+#include <ox/std/utility.hpp>
+
+#include <ox/fs/filesystem/filesystem.hpp>
+
+namespace ox {
+
+Result<const char*> MemFS::directAccess(const FileAddress &addr) const noexcept {
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			return directAccess(addr.getInode().value);
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			return directAccess(StringView(addr.getPath().value));
+		default:
+			return ox::Error(1);
+	}
+}
+
+Error FileSystem::read(const FileAddress &addr, void *buffer, std::size_t size) noexcept {
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			return readFileInode(addr.getInode().value, buffer, size);
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			return readFilePath(StringView(addr.getPath().value), buffer, size);
+		default:
+			return ox::Error(1);
+	}
+}
+
+Result<Buffer> FileSystem::read(FileAddress const &addr, size_t const size) noexcept {
+	Result<Buffer> out;
+	out.value.resize(size);
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			OX_RETURN_ERROR(readFileInode(addr.getInode().value, out.value.data(), size));
+			break;
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			OX_RETURN_ERROR(readFilePath(StringView{addr.getPath().value}, out.value.data(), size));
+			break;
+		default:
+			return ox::Error{1};
+	}
+	return out;
+}
+
+Result<Buffer> FileSystem::read(StringViewCR path, size_t const size) noexcept {
+	Result<Buffer> out;
+	out.value.resize(size);
+	OX_RETURN_ERROR(readFilePath(path, out.value.data(), size));
+	return out;
+}
+
+Result<Buffer> FileSystem::read(const FileAddress &addr) noexcept {
+	OX_REQUIRE(s, stat(addr));
+	Buffer buff(static_cast<std::size_t>(s.size));
+	OX_RETURN_ERROR(read(addr, buff.data(), buff.size()));
+	return buff;
+}
+
+Result<Buffer> FileSystem::read(StringViewCR path) noexcept {
+	OX_REQUIRE(s, statPath(path));
+	Buffer buff(static_cast<std::size_t>(s.size));
+	OX_RETURN_ERROR(readFilePath(path, buff.data(), buff.size()));
+	return buff;
+}
+
+Error FileSystem::read(
+		FileAddress const &addr,
+		std::size_t const readStart,
+		std::size_t const readSize,
+		void *buffer,
+		std::size_t *size) noexcept {
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			return readFileInodeRange(addr.getInode().value, readStart, readSize, buffer, size);
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			return readFilePathRange(addr.getPath().value, readStart, readSize, buffer, size);
+		default:
+			return ox::Error(1);
+	}
+}
+
+Result<size_t> FileSystem::read(
+		StringViewCR path,
+		std::size_t const readStart,
+		std::size_t const readSize,
+		Span<char> buff) noexcept {
+	size_t szOut{buff.size()};
+	OX_RETURN_ERROR(readFilePathRange(path, readStart, readSize, buff.data(), &szOut));
+	return szOut;
+}
+
+Error FileSystem::write(const FileAddress &addr, const void *buffer, uint64_t size, FileType fileType) noexcept {
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			return writeFileInode(addr.getInode().value, buffer, size, fileType);
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			return writeFilePath(StringView(addr.getPath().value), buffer, size, fileType);
+		default:
+			return ox::Error(1);
+	}
+}
+
+Result<FileStat> FileSystem::stat(const FileAddress &addr) const noexcept {
+	switch (addr.type()) {
+		case FileAddressType::Inode:
+			return statInode(addr.getInode().value);
+		case FileAddressType::ConstPath:
+		case FileAddressType::Path:
+			return statPath(StringView(addr.getPath().value));
+		default:
+			return ox::Error(1);
+	}
+}
+
+template class FileSystemTemplate<FileStore16, Directory16>;
+template class FileSystemTemplate<FileStore32, Directory32>;
+
+}

src/fs/src/filesystem/passthroughfs.cpp

@@ -0,0 +1,217 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/error.hpp>
+
+#include <ox/fs/filesystem/passthroughfs.hpp>
+
+#if defined(OX_HAS_PASSTHROUGHFS)
+
+#include <fstream>
+#include <string_view>
+
+namespace ox {
+
+PassThroughFS::PassThroughFS(StringViewCR dirPath) {
+	m_path = std::string_view(dirPath.data(), dirPath.bytes());
+}
+
+PassThroughFS::~PassThroughFS() noexcept = default;
+
+String PassThroughFS::basePath() const noexcept {
+	return ox::String(m_path.string().c_str());
+}
+
+Error PassThroughFS::mkdir(StringViewCR path, bool recursive) noexcept {
+	bool success = false;
+	const auto p = m_path / stripSlash(path);
+	const auto u8p = p.u8string();
+	oxTrace("ox.fs.PassThroughFS.mkdir", std::bit_cast<const char*>(u8p.c_str()));
+	if (recursive) {
+		std::error_code ec;
+		const auto isDir = std::filesystem::is_directory(p, ec);
+		if (isDir && !ec.value()) {
+			success = true;
+		} else {
+			success = std::filesystem::create_directories(p, ec);
+			OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: mkdir failed"));
+		}
+	} else {
+		std::error_code ec;
+		const auto isDir = std::filesystem::is_directory(p, ec);
+		if (isDir) {
+			success = true;
+		} else {
+			success = std::filesystem::create_directory(p, ec);
+			OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: mkdir failed"));
+		}
+	}
+	return ox::Error(success ? 0 : 1);
+}
+
+Error PassThroughFS::move(StringViewCR src, StringViewCR dest) noexcept {
+	std::error_code ec;
+	std::filesystem::rename(m_path / stripSlash(src), m_path / stripSlash(dest), ec);
+	if (ec.value()) {
+		return ox::Error(1);
+	}
+	return {};
+}
+
+Result<Vector<String>> PassThroughFS::ls(StringViewCR dir) const noexcept {
+	Vector<String> out;
+	std::error_code ec;
+	const auto di = std::filesystem::directory_iterator(m_path / stripSlash(dir), ec);
+	OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: ls failed"));
+	for (const auto &p : di) {
+		const auto u8p = p.path().filename().u8string();
+		out.emplace_back(reinterpret_cast<const char*>(u8p.c_str()));
+	}
+	return out;
+}
+
+Error PassThroughFS::resize(uint64_t, void*) noexcept {
+	// unsupported
+	return ox::Error(1, "resize is not supported by PassThroughFS");
+}
+
+Result<FileStat> PassThroughFS::statInode(uint64_t) const noexcept {
+	// unsupported
+	return ox::Error(1, "statInode(uint64_t) is not supported by PassThroughFS");
+}
+
+Result<FileStat> PassThroughFS::statPath(StringViewCR path) const noexcept {
+	std::error_code ec;
+	const auto p = m_path / stripSlash(path);
+	const FileType type = std::filesystem::is_directory(p, ec) ?
+		FileType::Directory : FileType::NormalFile;
+	oxTracef("ox.fs.PassThroughFS.statInode", "{} {}", ec.message(), path);
+	const uint64_t size = type == FileType::Directory ? 0 : std::filesystem::file_size(p, ec);
+	oxTracef("ox.fs.PassThroughFS.statInode.size", "{} {}", path, size);
+	if (auto err = ec.value()) {
+		return ox::Error{static_cast<ox::ErrorCode>(err), "PassThroughFS: stat failed"};
+	}
+	return FileStat{0, 0, size, type};
+}
+
+uint64_t PassThroughFS::spaceNeeded(uint64_t size) const noexcept {
+	return size;
+}
+
+Result<uint64_t> PassThroughFS::available() const noexcept {
+	std::error_code ec;
+	const auto s = std::filesystem::space(m_path, ec);
+	OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: could not get FS size"));
+	return s.available;
+}
+
+Result<uint64_t> PassThroughFS::size() const noexcept {
+	std::error_code ec;
+	const auto s = std::filesystem::space(m_path, ec);
+	OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(ec.value()), "PassThroughFS: could not get FS size"));
+	return s.capacity;
+}
+
+char *PassThroughFS::buff() noexcept {
+	return nullptr;
+}
+
+Error PassThroughFS::walk(Error(*)(uint8_t, uint64_t, uint64_t)) noexcept {
+	return ox::Error(1, "walk(Error(*)(uint8_t, uint64_t, uint64_t)) is not supported by PassThroughFS");
+}
+
+bool PassThroughFS::valid() const noexcept {
+	std::error_code ec;
+	const auto out = std::filesystem::is_directory(m_path, ec);
+	if (!ec.value()) {
+		return out;
+	}
+	return false;
+}
+
+Error PassThroughFS::readFilePath(StringViewCR path, void *buffer, std::size_t buffSize) noexcept {
+	try {
+		std::ifstream file((m_path / stripSlash(path)), std::ios::binary | std::ios::ate);
+		const std::size_t size = static_cast<std::size_t>(file.tellg());
+		file.seekg(0, std::ios::beg);
+		if (size > buffSize) {
+			oxTracef("ox.fs.PassThroughFS.read.error", "Read failed: Buffer too small: {}", path);
+			return ox::Error(1);
+		}
+		file.read(static_cast<char*>(buffer), static_cast<std::streamsize>(buffSize));
+	} catch (const std::fstream::failure &f) {
+		oxTracef("ox.fs.PassThroughFS.read.error", "Read of {} failed: {}", path, f.what());
+		return ox::Error(2);
+	}
+	return {};
+}
+
+Error PassThroughFS::readFileInode(uint64_t, void*, std::size_t) noexcept {
+	// unsupported
+	return ox::Error(1, "readFileInode(uint64_t, void*, std::size_t) is not supported by PassThroughFS");
+}
+
+Error PassThroughFS::readFilePathRange(
+	StringViewCR path, size_t const readStart, size_t readSize, void *buffer, size_t *buffSize) noexcept {
+	try {
+		std::ifstream file(m_path / stripSlash(path), std::ios::binary | std::ios::ate);
+		auto const size = static_cast<size_t>(file.tellg());
+		readSize = ox::min(readSize, size);
+		file.seekg(static_cast<off_t>(readStart), std::ios::beg);
+		if (readSize > *buffSize) {
+			oxTracef("ox.fs.PassThroughFS.read.error", "Read failed: Buffer too small: {}", path);
+			return ox::Error{1};
+		}
+		file.read(static_cast<char*>(buffer), static_cast<std::streamsize>(readSize));
+		return {};
+	} catch (std::fstream::failure const &f) {
+		oxTracef("ox.fs.PassThroughFS.read.error", "Read of {} failed: {}", path, f.what());
+		return ox::Error{2};
+	}
+}
+
+Error PassThroughFS::readFileInodeRange(uint64_t, std::size_t, std::size_t, void*, std::size_t*) noexcept {
+	// unsupported
+	return ox::Error(1, "read(uint64_t, std::size_t, std::size_t, void*, std::size_t*) is not supported by PassThroughFS");
+}
+
+Error PassThroughFS::removePath(StringViewCR path, bool const recursive) noexcept {
+	if (recursive) {
+		return ox::Error{std::filesystem::remove_all(m_path / stripSlash(path)) == 0};
+	} else {
+		return ox::Error{!std::filesystem::remove(m_path / stripSlash(path))};
+	}
+}
+
+Error PassThroughFS::writeFilePath(StringViewCR path, const void *buffer, uint64_t size, FileType) noexcept {
+	const auto p = (m_path / stripSlash(path));
+	try {
+		std::ofstream f(p, std::ios::binary);
+		f.write(static_cast<const char*>(buffer), static_cast<std::streamsize>(size));
+	} catch (const std::fstream::failure &f) {
+		oxTracef("ox.fs.PassThroughFS.read.error", "Write of {} failed: {}", path, f.what());
+		return ox::Error(1);
+	}
+	return {};
+}
+
+Error PassThroughFS::writeFileInode(uint64_t, const void*, uint64_t, FileType) noexcept {
+	// unsupported
+	return ox::Error(1, "writeFileInode(uint64_t, void*, uint64_t, uint8_t) is not supported by PassThroughFS");
+}
+
+std::string_view PassThroughFS::stripSlash(StringView path) noexcept {
+	for (auto i = 0u; i < path.size() && path[0] == '/'; i++) {
+		path = substr(path, 1);
+	}
+	return {path.data(), path.bytes()};
+}
+
+}
+
+#endif

src/fs/src/filesystem/pathiterator.cpp

@@ -0,0 +1,189 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/memops.hpp>
+#include <ox/std/strops.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/fs/filesystem/pathiterator.hpp>
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+PathIterator::PathIterator(const char *path, std::size_t maxSize, std::size_t iterator) {
+	m_path = path;
+	m_maxSize = maxSize;
+	m_iterator = iterator;
+}
+
+PathIterator::PathIterator(const char *path): PathIterator(path, ox::strlen(path)) {
+}
+
+PathIterator::PathIterator(StringViewCR path): PathIterator(path.data(), path.bytes()) {
+}
+
+/**
+ * @return 0 if no error
+ */
+Error PathIterator::dirPath(char *out, std::size_t outSize) {
+	const auto idx = ox::lastIndexOf(m_path, '/', m_maxSize);
+	const auto size = static_cast<std::size_t>(idx) + 1;
+	if (idx >= 0 && size < outSize) {
+		ox::memcpy(out, m_path, size);
+		out[size] = 0;
+		return {};
+	} else {
+		return ox::Error(1);
+	}
+}
+
+// Gets the get item in the path
+Error PathIterator::get(StringView &fileName) {
+	std::size_t size = 0;
+	if (m_iterator >= m_maxSize) {
+		oxTracef("ox.fs.PathIterator.get", "m_iterator ({}) >= m_maxSize ({})", m_iterator, m_maxSize);
+		return ox::Error(1);
+	}
+	if (!ox::strlen(&m_path[m_iterator])) {
+		oxTrace("ox.fs.PathIterator.get", "!ox::strlen(&m_path[m_iterator])");
+		return ox::Error(1);
+	}
+	auto start = m_iterator;
+	if (m_path[start] == '/') {
+		start++;
+	}
+	// end is at the next /
+	const char *substr = ox::strchr(&m_path[start], '/', m_maxSize - start);
+	// correct end if it is invalid, which happens if there is no next /
+	if (!substr) {
+		substr = ox::strchr(&m_path[start], 0, m_maxSize - start);
+	}
+	const auto end = static_cast<size_t>(substr - m_path);
+	size = end - start;
+	// cannot fit the output in the output parameter
+	if (size >= MaxFileNameLength || size == 0) {
+		return ox::Error(1);
+	}
+	fileName = ox::substr(m_path, start, start + size);
+	// truncate trailing /
+	if (size && fileName[size - 1] == '/') {
+		fileName = ox::substr(m_path, start, start + size - 1);
+	}
+	oxAssert(fileName[fileName.size()-1] != '/', "name ends in /");
+	return {};
+}
+
+/**
+ * @return 0 if no error
+ */
+Error PathIterator::next(StringView &fileName) {
+	std::size_t size = 0;
+	auto retval = ox::Error(1);
+	if (m_iterator < m_maxSize && ox::strlen(&m_path[m_iterator])) {
+		retval = {};
+		if (m_path[m_iterator] == '/') {
+			m_iterator++;
+		}
+		const auto start = m_iterator;
+		// end is at the next /
+		const char *substr = ox::strchr(&m_path[start], '/', m_maxSize - start);
+		// correct end if it is invalid, which happens if there is no next /
+		if (!substr) {
+			substr = ox::strchr(&m_path[start], 0, m_maxSize - start);
+		}
+		const auto end = static_cast<size_t>(substr - m_path);
+		size = end - start;
+		// cannot fit the output in the output parameter
+		if (size >= MaxFileNameLength) {
+			return ox::Error(1);
+		}
+		fileName = ox::substr(m_path, start, start + size);
+		// truncate trailing /
+		while (fileName.size() && fileName[fileName.size() - 1] == '/') {
+			fileName = ox::substr(m_path, start, start + size);
+		}
+		m_iterator += size;
+		oxAssert(fileName.size() == 0 || fileName[fileName.size()-1] != '/', "name ends in /");
+	}
+	return retval;
+}
+
+Result<std::size_t> PathIterator::nextSize() const {
+	std::size_t size = 0;
+	auto retval = ox::Error(1);
+	auto it = m_iterator;
+	if (it < m_maxSize && ox::strlen(&m_path[it])) {
+		retval = {};
+		if (m_path[it] == '/') {
+			it++;
+		}
+		const auto start = it;
+		// end is at the next /
+		const char *substr = ox::strchr(&m_path[start], '/', m_maxSize - start);
+		// correct end if it is invalid, which happens if there is no next /
+		if (!substr) {
+			substr = ox::strchr(&m_path[start], 0, m_maxSize - start);
+		}
+		const auto end = static_cast<std::size_t>(substr - m_path);
+		size = end - start;
+	}
+	it += size;
+	return {size, retval};
+}
+
+bool PathIterator::hasNext() const {
+	std::size_t size = 0;
+	if (m_iterator < m_maxSize && ox::strlen(&m_path[m_iterator])) {
+		std::size_t start = m_iterator;
+		if (m_path[start] == '/') {
+			start++;
+		}
+		// end is at the next /
+		const char *substr = ox::strchr(&m_path[start], '/', m_maxSize - start);
+		// correct end if it is invalid, which happens if there is no next /
+		if (!substr) {
+			substr = ox::strchr(&m_path[start], 0, m_maxSize - start);
+		}
+		const auto end = static_cast<std::size_t>(substr - m_path);
+		size = end - start;
+	}
+	return size > 0;
+}
+
+bool PathIterator::valid() const {
+	return m_iterator < m_maxSize && m_path[m_iterator] != 0;
+}
+
+PathIterator PathIterator::next() const {
+	std::size_t size = 0;
+	auto iterator = m_iterator;
+	if (iterator < m_maxSize && ox::strlen(&m_path[iterator])) {
+		if (m_path[iterator] == '/') {
+			iterator++;
+		}
+		const auto start = iterator;
+		// end is at the next /
+		const char *substr = ox::strchr(&m_path[start], '/', m_maxSize - start);
+		// correct end if it is invalid, which happens if there is no next /
+		if (!substr) {
+			substr = ox::strchr(&m_path[start], 0, m_maxSize - start);
+		}
+		const auto end = static_cast<std::size_t>(substr - m_path);
+		size = end - start;
+	}
+	iterator += size;
+	return {m_path, m_maxSize, iterator + 1};
+}
+
+const char *PathIterator::fullPath() const {
+	return m_path;
+}
+
+}
+
+OX_CLANG_NOWARN_END

src/fs/src/tool.cpp

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <cstdio>
+#include <fstream>
+
+#include <ox/fs/fs.hpp>
+
+struct Buff {
+	char *data = nullptr;
+	std::size_t size = 0;
+};
+
+static ox::Result<Buff> loadFsBuff(const char *path) noexcept {
+	std::ifstream file(path, std::ios::binary | std::ios::ate);
+	if (!file.good()) {
+		oxErrorf("Could not find OxFS file: {}", path);
+		return ox::Error(1, "Could not find OxFS file");
+	}
+	try {
+		const auto size = static_cast<std::size_t>(file.tellg());
+		file.seekg(0, std::ios::beg);
+		const auto buff = new char[size];
+		file.read(buff, static_cast<std::streamsize>(size));
+		return Buff{buff, size};
+	} catch (const std::ios_base::failure &e) {
+		oxErrorf("Could not read OxFS file: {}", e.what());
+		return ox::Error(2, "Could not read OxFS file");
+	}
+}
+
+static ox::Result<ox::UPtr<ox::FileSystem>> loadFs(const char *path) noexcept {
+	OX_REQUIRE(buff, loadFsBuff(path));
+	return {ox::make_unique<ox::FileSystem32>(buff.data, buff.size)};
+}
+
+static ox::Error runLs(ox::FileSystem *fs, ox::Span<const char*> args) noexcept {
+	if (args.size() < 2) {
+		oxErr("Must provide a directory to ls\n");
+		return ox::Error(1);
+	}
+	OX_REQUIRE(files, fs->ls(args[1]));
+	for (const auto &file : files) {
+		oxOutf("{}\n", file);
+	}
+	return {};
+}
+
+static ox::Error runRead(ox::FileSystem *fs, ox::Span<const char*> args) noexcept {
+	if (args.size() < 2) {
+		oxErr("Must provide a path to a file to read\n");
+		return ox::Error(1);
+	}
+	OX_REQUIRE(buff, fs->read(ox::StringView(args[1])));
+	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+	std::ignore = fwrite(buff.data(), sizeof(decltype(buff)::value_type), buff.size(), stdout);
+	OX_ALLOW_UNSAFE_BUFFERS_END
+	return {};
+}
+
+static ox::Error run(int argc, const char **argv) noexcept {
+	if (argc < 3) {
+		oxErr("OxFS file and subcommand arguments are required\n");
+		return ox::Error(1);
+	}
+	auto const args = ox::Span{argv, static_cast<size_t>(argc)};
+	auto const fsPath = args[1];
+	ox::String subCmd(args[2]);
+	OX_REQUIRE(fs, loadFs(fsPath));
+	if (subCmd == "ls") {
+		return runLs(fs.get(), args + 2);
+	} else if (subCmd == "read") {
+		return runRead(fs.get(), args + 2);
+	}
+	return ox::Error(1);
+}
+
+int main(int argc, const char **argv) {
+	auto err = run(argc, argv);
+	oxAssert(err, "unhandled error");
+	return static_cast<int>(err);
+}

src/fs/test/CMakeLists.txt

@@ -0,0 +1,27 @@
+add_executable(
+	FSTests
+		tests.cpp
+)
+
+target_link_libraries(
+	FSTests
+		OxFS
+		OxMetalClaw
+)
+
+add_test("[ox/fs] PtrArith::setSize" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PtrArith::setSize)
+
+add_test("[ox/fs] PathIterator::next1" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::next1)
+add_test("[ox/fs] PathIterator::next2" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::next2)
+add_test("[ox/fs] PathIterator::next3" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::next3)
+add_test("[ox/fs] PathIterator::next4" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::next4)
+add_test("[ox/fs] PathIterator::next5" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::next5)
+add_test("[ox/fs] PathIterator::hasNext" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::hasNext)
+
+add_test("[ox/fs] PathIterator::dirPath" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests PathIterator::dirPath)
+
+add_test("[ox/fs] NodeBuffer::insert" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests "NodeBuffer::insert")
+add_test("[ox/fs] FileStore::readWrite" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests "FileStore::readWrite")
+
+add_test("[ox/fs] Directory" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests "Directory")
+add_test("[ox/fs] FileSystem" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/FSTests "FileSystem")

src/fs/test/tests.cpp

@@ -0,0 +1,249 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+// make sure asserts are enabled for the test file
+#undef NDEBUG
+
+#include <functional>
+#include <map>
+#include <string_view>
+#include <ox/std/std.hpp>
+#include <ox/fs/ptrarith/nodebuffer.hpp>
+#include <ox/fs/filestore/filestoretemplate.hpp>
+#include <ox/fs/filesystem/filesystem.hpp>
+
+template<typename T>
+struct OX_PACKED NodeType: public ox::ptrarith::Item<T> {
+	public:
+		[[nodiscard]]
+		size_t fullSize() const {
+			return this->size() + sizeof(*this);
+		}
+};
+
+const std::map<ox::StringView, std::function<ox::Error(ox::StringView)>> tests = {
+	{
+		{
+			"PtrArith::setSize",
+			[](ox::StringView) {
+				using BuffPtr_t = uint32_t;
+				ox::Vector<char> buff(5 * ox::units::MB);
+				auto buffer = new (buff.data()) ox::ptrarith::NodeBuffer<BuffPtr_t, NodeType<BuffPtr_t>>(buff.size());
+				using String = ox::IString<6>;
+				auto a1 = buffer->malloc(sizeof(String)).value;
+				auto a2 = buffer->malloc(sizeof(String)).value;
+				oxAssert(a1.valid(), "Allocation 1 failed.");
+				oxAssert(a2.valid(), "Allocation 2 failed.");
+				auto s1Buff = buffer->dataOf<String>(a1);
+				auto s2Buff = buffer->dataOf<String>(a2);
+				oxAssert(s1Buff.valid(), "s1 allocation 1 failed.");
+				oxAssert(s2Buff.valid(), "s2 allocation 2 failed.");
+				auto &s1 = *new (s1Buff) String("asdf");
+				auto &s2 = *new (s2Buff) String("aoeu");
+				oxTrace("test") << "s1: " << s1.c_str();
+				oxTrace("test") << "s2: " << s2.c_str();
+				oxAssert(s1 == "asdf", "Allocation 1 not as expected.");
+				oxAssert(s2 == "aoeu", "Allocation 2 not as expected.");
+				oxAssert(buffer->free(a1), "Free failed.");
+				oxAssert(buffer->free(a2), "Free failed.");
+				oxAssert(buffer->setSize(buffer->size() - buffer->available()), "Resize failed.");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::next1",
+			[](ox::StringView) {
+				auto constexpr path = ox::StringLiteral("/usr/share/charset.gbag");
+				ox::PathIterator it(path.c_str(), path.size());
+				ox::StringView buff;
+				oxAssert(it.next(buff) == 0 && buff == "usr", "PathIterator shows wrong next");
+				oxAssert(it.next(buff) == 0 && buff == "share", "PathIterator shows wrong next");
+				oxAssert(it.next(buff) == 0 && buff == "charset.gbag", "PathIterator shows wrong next");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::next2",
+			[](ox::StringView) {
+				auto constexpr path = ox::StringView("/usr/share/");
+				ox::PathIterator it(path);
+				ox::StringView buff;
+				oxAssert(it.next(buff), "PathIterator::next returned error");
+				ox::expect(buff, "usr");
+				oxAssert(it.next(buff), "PathIterator::next returned error");
+				ox::expect(buff, "share");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::next3",
+			[](ox::StringView) {
+				auto const path = ox::String("/");
+				ox::PathIterator it(path.c_str(), path.size());
+				ox::StringView buff;
+				oxAssert(it.next(buff) == 0 && buff == "\0", "PathIterator shows wrong next");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::next4",
+			[](ox::StringView) {
+				auto constexpr path = ox::StringLiteral("usr/share/charset.gbag");
+				ox::PathIterator it(path);
+				ox::StringView buff;
+				oxAssert(it.next(buff) == 0 && buff == "usr", "PathIterator shows wrong next");
+				oxAssert(it.next(buff) == 0 && buff == "share", "PathIterator shows wrong next");
+				oxAssert(it.next(buff) == 0 && buff == "charset.gbag", "PathIterator shows wrong next");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::next5",
+			[](ox::StringView) {
+				auto const path = ox::String("usr/share/");
+				ox::PathIterator it(path.c_str(), path.size());
+				ox::StringView buff;
+				oxAssert(it.next(buff) == 0 && buff == "usr", "PathIterator shows wrong next");
+				oxAssert(it.next(buff) == 0 && buff == "share", "PathIterator shows wrong next");
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::dirPath",
+			[] (ox::StringView) {
+				auto constexpr path = ox::StringLiteral("/usr/share/charset.gbag");
+				ox::PathIterator it(path.c_str(), path.size());
+				auto buff = static_cast<char*>(ox_alloca(path.size() + 1));
+				OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+				oxAssert(it.dirPath(buff, path.size()) == 0 && ox::strcmp(buff, "/usr/share/") == 0, "PathIterator shows incorrect dir path");
+				OX_ALLOW_UNSAFE_BUFFERS_END
+				return ox::Error(0);
+			}
+		},
+		{
+			"PathIterator::hasNext",
+			[](ox::StringView) {
+				const auto path = "/file1";
+				OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+				ox::PathIterator it(path, ox::strlen(path));
+				OX_ALLOW_UNSAFE_BUFFERS_END
+				oxAssert(it.hasNext(), "PathIterator shows incorrect hasNext");
+				oxAssert(!it.next().hasNext(), "PathIterator shows incorrect hasNext");
+				return ox::Error(0);
+			}
+		},
+		{
+			"Ptr::subPtr",
+			[](ox::StringView) {
+				constexpr auto buffLen = 5000;
+				ox::ptrarith::Ptr<uint8_t, uint32_t> p(ox_alloca(buffLen), buffLen, 500, 500);
+				oxAssert(p.valid(), "Ptr::subPtr: Ptr p is invalid.");
+
+				auto subPtr = p.subPtr<uint64_t>(50);
+				oxAssert(subPtr.valid(), "Ptr::subPtr: Ptr subPtr is invalid.");
+				return ox::Error(0);
+			}
+		},
+		{
+			"NodeBuffer::insert",
+			[](ox::StringView) {
+				constexpr auto buffLen = 5000;
+				auto list = new (ox_alloca(buffLen)) ox::ptrarith::NodeBuffer<uint32_t, ox::FileStoreItem<uint32_t>>(buffLen);
+				oxAssert(list->malloc(50).value.valid(), "NodeBuffer::insert: malloc 1 failed");
+				oxAssert(list->malloc(50).value.valid(), "NodeBuffer::insert: malloc 2 failed");
+				auto first = list->firstItem();
+				oxAssert(first.valid(), "NodeBuffer::insert: Could not access first item");
+				oxAssert(first->size() == 50, "NodeBuffer::insert: First item size invalid");
+				return ox::Error(0);
+			}
+		},
+		{
+			"FileStore::readWrite",
+			[](ox::StringView) {
+				constexpr auto buffLen = 5000;
+				constexpr auto str1 = "Hello, World!";
+				OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+				constexpr auto str1Len = ox::strlen(str1) + 1;
+				constexpr auto str2 = "Hello, Moon!";
+				constexpr auto str2Len = ox::strlen(str2) + 1;
+				OX_ALLOW_UNSAFE_BUFFERS_END
+				auto list = new (ox_alloca(buffLen)) ox::ptrarith::NodeBuffer<uint32_t, ox::FileStoreItem<uint32_t>>(buffLen);
+				oxAssert(ox::FileStore32::format(list, buffLen), "FileStore::format failed.");
+				ox::FileStore32 fileStore(list, buffLen);
+				oxAssert(fileStore.write(4, str1, str1Len, 1), "FileStore::write 1 failed.");
+				oxAssert(fileStore.write(5, str2, str2Len, 1), "FileStore::write 2 failed.");
+
+				char str1Read[str1Len];
+				size_t str1ReadSize = 0;
+				oxAssert(fileStore.read(4, reinterpret_cast<void*>(str1Read), str1Len, &str1ReadSize), "FileStore::read 1 failed.");
+
+				return ox::Error(0);
+			}
+		},
+		{
+			"Directory",
+			[](ox::StringView) {
+				ox::Vector<uint8_t> fsBuff(5000);
+				oxAssert(ox::FileStore32::format(fsBuff.data(), fsBuff.size()), "FS format failed");
+				ox::FileStore32 fileStore(fsBuff.data(), fsBuff.size());
+				ox::Directory32 dir(fileStore, 105);
+
+				oxTrace("ox.fs.test.Directory") << "Init";
+				oxAssert(dir.init(), "Init failed");
+
+				oxTrace("ox.fs.test.Directory") << "write 1";
+				oxAssert(dir.write("/file1", 1), "Directory write of file1 failed");
+
+				oxTrace("ox.fs.test.Directory") << "find";
+				oxAssert(dir.find("file1").error, "Could not find file1");
+				oxAssert(dir.find("file1").value == 1, "Could not find file1");
+
+				oxTrace("ox.fs.test.Directory") << "write 2";
+				oxAssert(dir.write("/file3", 3), "Directory write of file3 failed");
+
+				oxTrace("ox.fs.test.Directory") << "write 3";
+				oxAssert(dir.write("/file2", 2), "Directory write of file2 failed");
+
+				return ox::Error(0);
+			}
+		},
+		{
+			"FileSystem",
+			[](ox::StringView) {
+				ox::Vector<uint8_t> fsBuff(5000);
+				oxTrace("ox.fs.test.FileSystem") << "format";
+				oxAssert(ox::FileSystem32::format(fsBuff.data(), fsBuff.size()), "FileSystem format failed");
+				ox::FileSystem32 fs(ox::FileStore32(fsBuff.data(), fsBuff.size()));
+				oxTrace("ox.fs.test.FileSystem") << "mkdir";
+				oxAssert(fs.mkdir("/dir", true), "mkdir failed");
+				oxAssert(fs.stat("/dir").error, "mkdir failed");
+				oxAssert(fs.mkdir("/l1d1/l2d1/l3d1", true), "mkdir failed");
+				oxAssert(fs.stat("/l1d1/l2d1/l3d1").error, "mkdir failed");
+				oxAssert(fs.mkdir("/l1d1/l2d2", true), "mkdir failed");
+				oxAssert(fs.stat("/l1d1/l2d2").error, "mkdir failed");
+				return ox::Error(0);
+			}
+		},
+	},
+};
+
+int main(int argc, const char **argv) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+		return -1;
+	}
+	auto const args = ox::Span{argv, static_cast<size_t>(argc)};
+	ox::StringView const testName = args[1];
+	ox::StringView const testArg = argc >= 3 ? args[2] : nullptr;
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(testArg), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/logconn/CMakeLists.txt

@@ -0,0 +1,44 @@
+cmake_minimum_required(VERSION 3.10)
+
+add_library(
+	OxLogConn
+		src/logconn.cpp
+)
+
+set_property(
+	TARGET
+		OxLogConn
+	PROPERTY
+		POSITION_INDEPENDENT_CODE ON
+)
+
+if(NOT MSVC)
+	target_compile_options(OxLogConn PRIVATE -Wsign-conversion)
+endif()
+
+target_link_libraries(
+	OxLogConn PUBLIC
+		OxStd
+		OxMetalClaw
+		$<$<BOOL:${OX_OS_FREEBSD}>:pthread>
+		$<$<BOOL:${OX_OS_WINDOWS}>:ws2_32>
+)
+
+target_include_directories(
+	OxLogConn PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS
+		OxLogConn
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)

src/logconn/include/ox/logconn/circularbuff.hpp

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/assert.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/units.hpp>
+
+namespace ox::detail {
+
+class CirculerBuffer {
+	private:
+		std::size_t m_readPt = 0;
+		std::size_t m_writePt = 0;
+		ox::Buffer m_buff = ox::Buffer(ox::units::MB);
+
+	private:
+		[[nodiscard]]
+		constexpr auto avail() const noexcept {
+			if (m_writePt >= m_readPt) {
+				return m_buff.size() - (m_writePt - m_readPt);
+			} else {
+				return (m_buff.size() - m_writePt) - (m_buff.size() - m_readPt);
+			}
+		}
+
+	public:
+		constexpr ox::Error put(char v) noexcept {
+			return write(&v, 1);
+			if (1 > avail()) {
+				return ox::Error(1, "Insufficient space in buffer");
+			}
+			m_buff[m_writePt] = v;
+			++m_writePt;
+			return {};
+		}
+
+		constexpr ox::Error write(const char *buff, std::size_t sz) noexcept {
+			if (sz > avail()) {
+				return ox::Error(1, "Insufficient space in buffer");
+			}
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			// write seg 1
+			const auto seg1Sz = ox::min(sz, m_buff.size() - m_writePt);
+			ox::listcpy(&m_buff[m_writePt], &buff[0], seg1Sz);
+			m_writePt += sz;
+			if (seg1Sz != sz) {
+				m_writePt -= m_buff.size();
+				// write seg 2
+				const auto seg2Sz = sz - seg1Sz;
+				ox::listcpy(&m_buff[0], &buff[seg1Sz], seg2Sz);
+				oxAssert(m_buff[0] == buff[seg1Sz], "break");
+			}
+OX_ALLOW_UNSAFE_BUFFERS_END
+			return {};
+		}
+
+		constexpr ox::Error seekp(std::size_t bytesFwd) noexcept {
+			if (bytesFwd > avail()) {
+				return ox::Error(1, "Insufficient space in buffer to seek that far ahead");
+			}
+			m_writePt += bytesFwd;
+			if (m_writePt > m_buff.size()) {
+				m_writePt -= m_buff.size();
+			}
+			return {};
+		}
+
+		constexpr ox::Error seekp(int, ios_base::seekdir) noexcept {
+			return ox::Error(1, "Unimplemented");
+		}
+
+		[[nodiscard]]
+		constexpr std::size_t tellp() const noexcept {
+			return m_buff.size() - avail();
+		}
+
+		[[nodiscard]]
+		constexpr std::size_t read(char *out, std::size_t outSize) noexcept {
+			const auto bytesRead = ox::min(outSize, m_buff.size() - avail());
+			// read seg 1
+			const auto seg1Sz = ox::min(bytesRead, m_buff.size() - m_readPt);
+			ox::listcpy(&out[0], &m_buff[m_readPt], seg1Sz);
+			m_readPt += bytesRead;
+			if (seg1Sz != bytesRead) {
+				m_readPt -= m_buff.size();
+				// read seg 2
+				const auto seg2Sz = bytesRead - seg1Sz;
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+				ox::listcpy(&out[seg1Sz], &m_buff[0], seg2Sz);
+OX_ALLOW_UNSAFE_BUFFERS_END
+			}
+			return bytesRead;
+		}
+};
+
+}

src/logconn/include/ox/logconn/def.hpp

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#if defined(DEBUG) && !defined(OX_BARE_METAL)
+#define OX_INIT_DEBUG_LOGGER(loggerName, appName) \
+	ox::LoggerConn loggerName; \
+    { \
+		const auto loggerErr = (loggerName).initConn(appName); \
+		if (loggerErr) { \
+			oxErrf("Could not connect to logger: {} ({}:{})\n", toStr(loggerErr), loggerErr.src.file_name(), loggerErr.src.line()); \
+		} else { \
+			ox::trace::setLogger(&(loggerName)); \
+		} \
+		ox::trace::init(); \
+	}
+#else
+#define OX_INIT_DEBUG_LOGGER(loggerName, appName)
+#endif
+
+

src/logconn/include/ox/logconn/logconn.hpp

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#ifdef OX_USE_STDLIB
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+#endif
+
+#include <ox/mc/write.hpp>
+#include <ox/std/trace.hpp>
+
+#include "circularbuff.hpp"
+
+namespace ox {
+
+#ifdef OX_USE_STDLIB
+class LoggerConn: public trace::Logger {
+	private:
+		int m_socket = 0;
+		detail::CirculerBuffer m_buff;
+		std::thread m_netThread;
+		std::condition_variable m_waitCond;
+		std::mutex m_waitMut;
+		std::mutex m_buffMut;
+		bool m_running = true;
+	public:
+		LoggerConn() noexcept;
+		LoggerConn(const LoggerConn&) noexcept = delete;
+		~LoggerConn() noexcept override;
+		LoggerConn &operator=(const LoggerConn&) noexcept = delete;
+		ox::Error send(const trace::TraceMsg&) noexcept final;
+		ox::Error sendInit(const trace::InitTraceMsg&) noexcept final;
+		ox::Error initConn(ox::StringViewCR appName) noexcept;
+		ox::Error send(const char *buff, std::size_t len) const noexcept;
+	private:
+		void msgSend() noexcept;
+		ox::Error send(trace::MsgId msgId, const auto &msg) noexcept {
+			ox::Array<char, 10 * ox::units::KB> buff;
+			std::size_t sz = 0;
+			OX_RETURN_ERROR(ox::writeMC(&buff[0], buff.size(), msg, &sz));
+			//std::printf("sz: %lu\n", sz);
+			OX_REQUIRE(szBuff, serialize(static_cast<uint32_t>(sz)));
+			std::unique_lock buffLk(m_buffMut);
+			OX_RETURN_ERROR(m_buff.put(static_cast<char>(msgId)));
+			OX_RETURN_ERROR(m_buff.write(szBuff.data(), szBuff.size()));
+			OX_RETURN_ERROR(m_buff.write(buff.data(), sz));
+			buffLk.unlock();
+			m_waitCond.notify_one();
+			return {};
+		}
+
+};
+
+#else
+
+class LoggerConn: public trace::Logger {
+	private:
+	public:
+		constexpr LoggerConn() noexcept = default;
+		LoggerConn(const LoggerConn&) noexcept = delete;
+		constexpr ~LoggerConn() noexcept override = default;
+		LoggerConn &operator=(const LoggerConn&) noexcept = delete;
+		ox::Error send(const trace::TraceMsg&) noexcept final { return {}; }
+		static ox::Error initConn() noexcept { return {}; }
+		static ox::Error send(const char*, std::size_t) noexcept { return {}; }
+};
+#endif
+
+}
+

src/logconn/src/logconn.cpp

@@ -0,0 +1,120 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#ifdef OX_USE_STDLIB
+#include <cstdio>
+
+#ifndef _WIN32
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#else
+#include <winsock.h>
+#undef interface
+#undef min
+#undef max
+#endif
+
+
+#include <ox/logconn/logconn.hpp>
+
+
+namespace ox {
+
+#ifdef _WIN32
+using Socket = SOCKET;
+using LenType = int;
+#else
+using Socket = int;
+using LenType = size_t;
+#endif
+
+using namespace trace;
+
+static void closeSock(auto s) noexcept {
+#ifdef _WIN32
+	closesocket(static_cast<Socket>(s));
+#else
+	close(s);
+#endif
+}
+
+LoggerConn::LoggerConn() noexcept: m_netThread([this]{this->msgSend();}) {
+}
+
+LoggerConn::~LoggerConn() noexcept {
+	m_running = false;
+	m_waitCond.notify_one();
+	m_netThread.join();
+	if (m_socket) {
+		closeSock(m_socket);
+	}
+}
+
+ox::Error LoggerConn::initConn(ox::StringViewCR appName) noexcept {
+	sockaddr_in addr{};
+	addr.sin_family = AF_INET;
+	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+	addr.sin_port = htons(5590);
+	m_socket = static_cast<int>(socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
+	OX_RETURN_ERROR(ox::Error(static_cast<ox::ErrorCode>(connect(static_cast<Socket>(m_socket), reinterpret_cast<sockaddr*>(&addr), sizeof(addr)))));
+	return sendInit({.appName = ox::BasicString<128>(appName)});
+}
+
+ox::Error LoggerConn::send(const char *buff, std::size_t len) const noexcept {
+	std::size_t totalSent = 0;
+	while (totalSent < len) {
+		//std::fprintf(stdout, "Sending %lu/%lu bytes on socket %d\n", len, totalSent, m_socket);
+		const auto sent = ::send(static_cast<Socket>(m_socket), buff, static_cast<LenType>(len), 0);
+		if (sent < 0) {
+			std::ignore = std::fprintf(stderr, "Could not send msg\n");
+			return ox::Error(1, "Could not send msg");
+		}
+		totalSent += static_cast<std::size_t>(sent);
+	}
+	return {};
+}
+
+ox::Error LoggerConn::send(const TraceMsg &msg) noexcept {
+	return send(MsgId::TraceEvent, msg);
+}
+
+ox::Error LoggerConn::sendInit(const InitTraceMsg &msg) noexcept {
+	return send(MsgId::Init, msg);
+}
+
+void LoggerConn::msgSend() noexcept {
+	try {
+		while (true) {
+			std::unique_lock lk(m_waitMut);
+			m_waitCond.wait(lk);
+			if (!m_running) {
+				break;
+			}
+			std::lock_guard const buffLk(m_buffMut);
+			while (true) {
+				Array<char, units::KB> tmp;
+				const auto read = m_buff.read(tmp.data(), tmp.size());
+				if (!read) {
+					break;
+				}
+				oxAssert(read <= tmp.size(), "logger trying to read too much data");
+				//std::printf("LoggerConn: sending %lu bytes\n", read);
+				std::ignore = send(tmp.data(), read);
+			}
+		}
+	} catch (std::exception const &e) {
+		oxErrf("Exception in logger thread: {}\n", e.what());
+		oxAssert(false, "logger thread exception");
+	}
+}
+
+}
+#endif

src/mc/CMakeLists.txt

@@ -0,0 +1,47 @@
+add_library(
+	OxMetalClaw
+		src/read.cpp
+		src/write.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxMetalClaw PRIVATE -Wsign-conversion)
+	target_compile_options(OxMetalClaw PRIVATE -Wconversion)
+endif()
+
+target_link_libraries(
+	OxMetalClaw PUBLIC
+		OxModel
+		OxStd
+)
+
+if(NOT OX_BARE_METAL)
+	set_property(
+		TARGET
+			OxMetalClaw
+		PROPERTY
+			POSITION_INDEPENDENT_CODE ON
+	)
+endif()
+
+target_include_directories(
+	OxMetalClaw PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS OxMetalClaw
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/mc/include/ox/mc/err.hpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+namespace ox {
+
+enum {
+	McPresenceMapOverflow = 1,
+	McBuffEnded = 2,
+	McOutputBuffEnded = 4
+};
+
+}

src/mc/include/ox/mc/intops.hpp

@@ -0,0 +1,199 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/array.hpp>
+#include <ox/std/assert.hpp>
+#include <ox/std/bit.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/math.hpp>
+#include <ox/std/memops.hpp>
+#include <ox/std/reader.hpp>
+
+namespace ox::mc {
+
+template<Integer_c T>
+static constexpr auto Bits = sizeof(T) << 3;
+
+/**
+ * Returns highest bit other than possible signed bit.
+ * Bit numbering starts at 0.
+ */
+template<Integer_c I>
+[[nodiscard]]
+constexpr size_t highestBit(I const val) noexcept {
+	unsigned shiftStart = sizeof(I) * 8 - 1;
+	// find the most significant non-sign indicator bit
+	size_t highestBit = 0;
+	// start at one bit lower if signed
+	if constexpr(is_signed_v<I>) {
+		--shiftStart;
+	}
+	for (auto i = shiftStart; i > 0; --i) {
+		auto const bitValue = (val >> i) & 1;
+		if (bitValue) {
+			highestBit = i;
+			break;
+		}
+	}
+	return highestBit;
+}
+
+static_assert(highestBit(static_cast<int8_t>(0b10000000)) == 0);
+static_assert(highestBit(~static_cast<int8_t>(-1)) == 0);
+static_assert(highestBit(~static_cast<int8_t>(-2)) == 0);
+static_assert(highestBit(~static_cast<int8_t>(-3)) == 1);
+static_assert(highestBit(1) == 0);
+static_assert(highestBit(2) == 1);
+static_assert(highestBit(4) == 2);
+static_assert(highestBit(8) == 3);
+static_assert(highestBit(static_cast<uint64_t>(1) << 31) == 31);
+static_assert(highestBit(static_cast<uint64_t>(1) << 63) == 63);
+
+struct McInt {
+	Array<uint8_t, 9> data{};
+	// length of integer in bytes
+	size_t length = 0;
+};
+
+template<Integer_c I>
+[[nodiscard]]
+constexpr McInt encodeInteger(I const pInput) noexcept {
+	auto const input = ResizedInt_t<I, 64>{pInput};
+	McInt out;
+	auto const inputNegative = is_signed_v<I> && input < 0;
+	// move input to uint64_t to allow consistent bit manipulation and to avoid
+	// overflow concerns
+	auto const val = std::bit_cast<uint64_t>(input);
+	if (val) {
+		// bits needed to represent number factoring in space possibly
+		// needed for signed bit
+		auto const highBit = inputNegative ? highestBit(~val) : highestBit(val);
+		auto const bits = highBit + 1 + (is_signed_v<I> ? 1 : 0);
+		// bytes needed to store value
+		size_t bytes = bits / 8 + (bits % 8 != 0);
+		auto const bitsAvailable = bytes * 8; // bits available to integer value
+		auto const bitsNeeded = bits + bytes;
+		// factor in bits needed for bytesIndicator (does not affect bytesIndicator)
+		// bits for integer + bits needed to represent bytes > bits available
+		if (bitsNeeded > bitsAvailable && bytes != 9) {
+			++bytes;
+		}
+		auto const bytesIndicator = onMask<uint8_t>(bytes - 1);
+		// ensure we are copying from little endian representation
+		LittleEndian<uint64_t> leVal = val;
+		if (inputNegative) {
+			leVal |= static_cast<uint64_t>(1 << (bitsNeeded - 1));
+		}
+		if (bytes == 9) {
+			out.data[0] = bytesIndicator;
+			OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			ox::memcpy(&out.data[1], &leVal, 8);
+			OX_ALLOW_UNSAFE_BUFFERS_END
+			if (inputNegative) {
+				out.data[1] |= 0b1000'0000;
+			}
+		} else {
+			auto const valBits = bytes * 8;
+			uint64_t const negBit = inputNegative ? 1 : 0;
+			auto const intermediate =
+				static_cast<uint64_t>(leVal.raw() | (negBit << (valBits - 1))) << bytes |
+				static_cast<uint64_t>(bytesIndicator);
+			OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			ox::memcpy(&out.data[0], &intermediate, sizeof(intermediate));
+			OX_ALLOW_UNSAFE_BUFFERS_END
+		}
+		out.length = bytes;
+	}
+	return out;
+}
+
+/**
+ * Returns the number of bytes indicated by the bytes indicator of a variable
+ * length integer.
+ */
+[[nodiscard]]
+constexpr size_t countBytes(unsigned const b) noexcept {
+	size_t i = 0;
+	while ((b >> i) & 1) ++i;
+	return i + 1;
+}
+
+static_assert(countBytes(0b0000'0000) == 1);
+static_assert(countBytes(0b0000'0001) == 2);
+static_assert(countBytes(0b0000'0011) == 3);
+static_assert(countBytes(0b0000'0111) == 4);
+static_assert(countBytes(0b0000'1111) == 5);
+static_assert(countBytes(0b0001'1111) == 6);
+static_assert(countBytes(0b0011'1111) == 7);
+static_assert(countBytes(0b0111'1111) == 8);
+static_assert(countBytes(0b1111'1111) == 9);
+
+template<Integer_c I>
+constexpr Result<I> decodeInteger(Reader_c auto &rdr, size_t &bytesRead) noexcept {
+	uint8_t firstByte = 0;
+	OX_RETURN_ERROR(rdr.read(&firstByte, 1));
+	OX_RETURN_ERROR(rdr.seekg(-1, ox::ios_base::cur));
+	auto const bytes = countBytes(firstByte);
+	if (bytes == 9) {
+		bytesRead = bytes;
+		I out = 0;
+		OX_RETURN_ERROR(rdr.seekg(1, ox::ios_base::cur));
+		OX_RETURN_ERROR(rdr.read(&out, sizeof(I)));
+		return fromLittleEndian<I>(out);
+	}
+	bytesRead = bytes;
+	uint64_t decoded = 0;
+	OX_RETURN_ERROR(rdr.read(&decoded, bytes));
+	decoded >>= bytes;
+	// move sign bit
+	if constexpr(is_signed_v<I>) {
+		auto const negBit = bytes * 8 - bytes - 1;
+		// move sign
+		auto const negative = (decoded >> negBit) == 1;
+		if (negative) {
+			// fill in all bits between encoded sign and real sign with 1s
+			// split it up because the 32-bit ARM can't shift more than 32 bits
+			Array<uint32_t, 2> d = {};
+			//d[0] = decoded & 0xffff'ffff;
+			//d[1] = decoded >> 32;
+		 	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			ox::memcpy(&d[0], &decoded, sizeof(decoded));
+		 	OX_ALLOW_UNSAFE_BUFFERS_END
+			auto bit = negBit;
+			for (; bit < ox::min<size_t>(Bits<I>, 32); ++bit) {
+				d[0] |= 1 << bit;
+			}
+			bit -= 32;
+			for (; bit < Bits<I>; ++bit) {
+				d[1] |= 1 << bit;
+			}
+			I out = 0;
+			if constexpr(ox::defines::BigEndian) {
+				auto const d0Tmp = d[0];
+				d[0] = d[1];
+				d[1] = d0Tmp;
+			}
+		 	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			ox::memcpy(&out, &d[0], sizeof(out));
+			OX_ALLOW_UNSAFE_BUFFERS_END
+			return out;
+		}
+	}
+	return static_cast<I>(decoded);
+}
+
+template<Integer_c I>
+Result<I> decodeInteger(McInt const &m) noexcept {
+	size_t bytesRead{};
+	BufferReader br({reinterpret_cast<const char*>(m.data.data()), 9});
+	return decodeInteger<I>(br, bytesRead);
+}
+
+}

src/mc/include/ox/mc/mc.hpp

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "intops.hpp"
+#include "read.hpp"
+#include "types.hpp"
+#include "write.hpp"

src/mc/include/ox/mc/presenceindicator.hpp

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/array.hpp>
+#include <ox/std/bit.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/span.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/reader.hpp>
+
+#include "err.hpp"
+
+namespace ox {
+
+template<Reader_c Reader>
+class FieldBitmapReader {
+	protected:
+		mutable size_t m_mapBlockIdx = ~size_t{};
+		mutable uint64_t m_mapBlock{};
+		size_t m_mapStart{};
+		Reader &m_reader;
+
+	public:
+		explicit constexpr FieldBitmapReader(Reader &reader) noexcept:
+			m_mapStart(reader.tellg()),
+			m_reader(reader) {
+		}
+
+		constexpr Result<bool> get(size_t idx) const noexcept {
+			constexpr auto blockBits = sizeof(m_mapBlock);
+			auto const blockIdx = idx / blockBits;
+			if (m_mapBlockIdx != blockIdx) [[unlikely]] {
+				OX_RETURN_ERROR(loadMapBlock(blockIdx));
+			}
+			idx %= blockBits;
+			return (m_mapBlock >> idx) & 1;
+		}
+
+	private:
+		constexpr Error loadMapBlock(size_t const idx) const noexcept {
+			OX_REQUIRE(g, m_reader.tellg());
+			OX_RETURN_ERROR(m_reader.seekg(static_cast<int>(m_mapStart + idx), ox::ios_base::beg));
+			Array<char, sizeof(m_mapBlock)> mapBlock{};
+			OX_RETURN_ERROR(m_reader.read(mapBlock.data(), sizeof(m_mapBlock)));
+			// Warning: narrow-conv
+			OX_RETURN_ERROR(m_reader.seekg(static_cast<int>(g), ox::ios_base::beg));
+			m_mapBlock = 0;
+			for (uint64_t i{}; auto b : mapBlock) {
+				m_mapBlock |= static_cast<uint64_t>(std::bit_cast<uint8_t>(b)) << i;
+				i += 8;
+			}
+			m_mapBlockIdx = idx;
+			return {};
+		}
+
+};
+
+
+class FieldBitmapWriter {
+	protected:
+		Span<char> m_map;
+		size_t m_mapLen{};
+
+	public:
+		explicit constexpr FieldBitmapWriter(Span<char> const &map) noexcept:
+			m_map(map),
+			m_mapLen(m_map.size()) {
+		}
+
+		constexpr auto setBuffer(Span<char> const &map) noexcept {
+			m_map = map;
+			m_mapLen = map.size();
+		}
+
+		constexpr Result<bool> get(size_t const i) const noexcept {
+			if (i / 8 < m_mapLen) {
+				return (std::bit_cast<uint8_t>(m_map[i / 8]) >> (i % 8)) & 1;
+			}
+			return Error{McPresenceMapOverflow};
+		}
+
+		constexpr Error setFields(int const fields) noexcept {
+			m_mapLen = static_cast<size_t>((fields / 8 + 1) - (fields % 8 == 0));
+			if (m_mapLen > m_map.size()) [[unlikely]] {
+				return Error{McPresenceMapOverflow};
+			}
+			return {};
+		}
+
+		constexpr void setMaxLen(int const maxLen) noexcept {
+			m_mapLen = static_cast<size_t>(maxLen);
+		}
+
+		constexpr int64_t getMaxLen() const noexcept {
+			return static_cast<int64_t>(m_mapLen);
+		}
+
+		constexpr Error set(size_t const i, bool const on) noexcept {
+			if (i / 8 < m_mapLen) {
+				char &actual = m_map[i / 8];
+				uint8_t v = std::bit_cast<uint8_t>(actual);
+				if (on) {
+					v |= 1 << (i % 8);
+				} else {
+					v &= ~static_cast<uint8_t>(1 << (i % 8));
+				}
+				actual = std::bit_cast<char>(v);
+				return {};
+			}
+			return Error{McPresenceMapOverflow};
+		}
+
+};
+
+}

src/mc/include/ox/mc/read.hpp

@@ -0,0 +1,558 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/model/fieldcounter.hpp>
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/typenamecatcher.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/optional.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/std/vector.hpp>
+
+#include "err.hpp"
+#include "intops.hpp"
+#include "presenceindicator.hpp"
+#include "types.hpp"
+
+namespace ox {
+
+template<Reader_c Reader>
+class MetalClawReaderTemplate: public ModelHandlerBase<MetalClawReaderTemplate<Reader>, ox::OpType::Read> {
+
+	private:
+		FieldBitmapReader<Reader> m_fieldPresence;
+		size_t m_fields{};
+		size_t m_field{};
+		Optional<int> const m_unionIdx{};
+		Reader &m_reader;
+
+	public:
+		explicit constexpr MetalClawReaderTemplate(
+				Reader &reader,
+				Optional<int> const &unionIdx = {}) noexcept;
+
+		constexpr ~MetalClawReaderTemplate() noexcept;
+
+		constexpr Error field(CString, int8_t *val) noexcept;
+		constexpr Error field(CString, int16_t *val) noexcept;
+		constexpr Error field(CString, int32_t *val) noexcept;
+		constexpr Error field(CString, int64_t *val) noexcept;
+
+		constexpr Error field(CString, uint8_t *val) noexcept;
+		constexpr Error field(CString, uint16_t *val) noexcept;
+		constexpr Error field(CString, uint32_t *val) noexcept;
+		constexpr Error field(CString, uint64_t *val) noexcept;
+
+		constexpr Error field(CString, bool *val) noexcept;
+
+		// array handler
+		constexpr Error field(CString, auto *val, size_t valLen) noexcept;
+
+		// map handler
+		template<typename T>
+		constexpr Error field(CString, HashMap<String, T> *val) noexcept;
+
+		// array handler, with callback to allow handling individual elements
+		template<typename T, typename CB>
+		constexpr Error field(CString, CB cb) noexcept;
+
+		template<typename T>
+		constexpr Error field(CString, T *val) noexcept;
+
+		template<typename U, bool force>
+		constexpr Error field(CString, UnionView<U, force> val) noexcept;
+
+		template<size_t SmallStringSize>
+		constexpr Error field(CString, BasicString<SmallStringSize> *val) noexcept;
+
+		template<size_t L>
+		constexpr Error field(CString, IString<L> *val) noexcept;
+
+		constexpr Error fieldCString(CString, char *val, size_t buffLen) noexcept;
+
+		constexpr Error fieldCString(CString, char **val) noexcept;
+
+		constexpr Error fieldCString(CString, char **val, size_t buffLen) noexcept;
+
+		/**
+		 * Reads an array length from the current location in the buffer.
+		 * @param pass indicates that the parsing should iterate past the array length
+		 */
+		constexpr Result<ArrayLength> arrayLength(const char *name, bool pass = true) noexcept;
+
+		/**
+		 * Reads an string length from the current location in the buffer.
+		 */
+		constexpr Result<StringLength> stringLength(const char *name) noexcept;
+
+		template<typename T = std::nullptr_t>
+		constexpr ox::Error setTypeInfo(
+				const char *name = T::TypeName,
+				int version = T::TypeVersion,
+				const Vector<String>& = {},
+				size_t fields = ModelFieldCount_v<T>) noexcept;
+
+		/**
+		 * Returns a MetalClawReader to parse a child object.
+		 */
+		[[nodiscard]]
+		constexpr MetalClawReaderTemplate<Reader> child(const char *name, Optional<int> unionIdx = {}) noexcept;
+
+		/**
+		 * Indicates whether or not the next field to be read is present.
+		 */
+		[[nodiscard]]
+		constexpr bool fieldPresent(const char *name) const noexcept;
+
+		/**
+		 * Indicates whether or not the given field is present.
+		 */
+		[[nodiscard]]
+		constexpr bool fieldPresent(int fieldNo) const noexcept;
+
+		[[nodiscard]]
+		constexpr int whichFieldPresent(const char *name, ModelUnion const&) const noexcept;
+
+		constexpr void nextField() noexcept;
+
+	private:
+		template<typename I>
+		constexpr Error readInteger(I &val) noexcept;
+
+};
+
+template<Reader_c Reader>
+constexpr MetalClawReaderTemplate<Reader>::MetalClawReaderTemplate(
+		Reader &reader,
+		Optional<int> const &unionIdx) noexcept:
+		m_fieldPresence(reader),
+		m_unionIdx(unionIdx),
+		m_reader(reader) {
+}
+
+template<Reader_c Reader>
+constexpr MetalClawReaderTemplate<Reader>::~MetalClawReaderTemplate() noexcept {
+	if (m_field != m_fields) {
+		oxTrace("ox.mc.MetalClawReader.error") << "MetalClawReader: incorrect fields number given";
+	}
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, int8_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, int16_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, int32_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, int64_t *val) noexcept {
+	return readInteger(*val);
+}
+
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, uint8_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, uint16_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, uint32_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, uint64_t *val) noexcept {
+	return readInteger(*val);
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, bool *val) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		auto const result = m_fieldPresence.get(static_cast<size_t>(m_field));
+		*val = result.value;
+		OX_RETURN_ERROR(result);
+	}
+	++m_field;
+	return {};
+}
+
+// array handler
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::field(
+	const char *name, auto *val, size_t const valLen) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(len, mc::decodeInteger<ArrayLength>(m_reader, bytesRead));
+			// read the list
+			if (valLen >= len) {
+				auto reader = child({});
+				auto &handler = *reader.interface();
+				OX_RETURN_ERROR(handler.setTypeInfo("List", 0, {}, static_cast<size_t>(len)));
+				for (size_t i = 0; i < len; ++i) {
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+					OX_RETURN_ERROR(handler.field({}, &val[i]));
+OX_ALLOW_UNSAFE_BUFFERS_END
+				}
+			} else {
+				oxTracef("ox.mc.read.field(T)", "{}, length: {}", name, valLen);
+				return ox::Error(McOutputBuffEnded);
+			}
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<typename T>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, HashMap<String, T> *val) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			OX_REQUIRE(g, m_reader.tellg());
+			size_t bytesRead = 0;
+			OX_REQUIRE(len, mc::decodeInteger<ArrayLength>(m_reader, bytesRead));
+			OX_RETURN_ERROR(m_reader.seekg(g));
+			// read the list
+			auto reader = child("");
+			auto &handler = *reader.interface();
+			OX_RETURN_ERROR(handler.setTypeInfo("List", 0, {}, static_cast<size_t>(len)));
+			// this loop body needs to be in a lambda because of the potential alloca call
+			constexpr auto loopBody = [](auto &handler, auto &val) {
+				OX_REQUIRE(keyLen, handler.stringLength(nullptr));
+				auto wkey = ox_malloca(keyLen + 1, char, 0);
+				auto wkeyPtr = wkey.get();
+				OX_RETURN_ERROR(handler.fieldCString("", &wkeyPtr, keyLen + 1));
+				return handler.field("", &val[wkeyPtr]);
+			};
+			for (size_t i = 0; i < len; ++i) {
+				OX_RETURN_ERROR(loopBody(handler, *val));
+			}
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<typename T>
+constexpr Error MetalClawReaderTemplate<Reader>::field(const char *name, T *val) noexcept {
+	if constexpr(isVector_v<T>) {
+		if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+			// set size of val if the field is present, don't worry about it if not
+			if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+				OX_REQUIRE(len, arrayLength(name, false));
+				OX_RETURN_ERROR(ox::resizeVector(*val, len));
+				return field(name, val->data(), val->size());
+			}
+			OX_RETURN_ERROR(ox::resizeVector(*val, 0));
+		}
+		++m_field;
+		return {};
+	} else if constexpr(isArray_v<T>) {
+		if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+			// set size of val if the field is present, don't worry about it if not
+			if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+				OX_REQUIRE(len, arrayLength(name, false));
+				if (len > val->size()) {
+					return ox::Error(1, "Input array is too long");
+				}
+			}
+			return field(name, val->data(), val->size());
+		}
+		++m_field;
+		return {};
+	} else {
+		if ((!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) && val) {
+			if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+				auto reader = child("");
+				OX_RETURN_ERROR(model(reader.interface(), val));
+			}
+		}
+		++m_field;
+		return {};
+	}
+}
+
+template<Reader_c Reader>
+template<typename U, bool force>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, UnionView<U, force> val) noexcept {
+	if ((!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) && val.get()) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			auto reader = child("", ox::Optional<int>(ox::in_place, val.idx()));
+			OX_RETURN_ERROR(model(reader.interface(), val.get()));
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<size_t SmallStringSize>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, BasicString<SmallStringSize> *val) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(size, mc::decodeInteger<StringLength>(m_reader, bytesRead));
+			const auto cap = size;
+			*val = BasicString<SmallStringSize>(cap);
+			auto data = val->data();
+			// read the string
+			OX_RETURN_ERROR(m_reader.read(data, size));
+		} else {
+			*val = "";
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<size_t L>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, IString<L> *val) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(size, mc::decodeInteger<StringLength>(m_reader, bytesRead));
+			*val = IString<L>();
+			OX_RETURN_ERROR(val->resize(size));
+			auto const data = val->data();
+			// read the string
+			OX_RETURN_ERROR(m_reader.read(data, size));
+		} else {
+			*val = "";
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::fieldCString(
+	CString, char *val, size_t const buffLen) noexcept {
+	if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+		// read the length
+		size_t bytesRead = 0;
+		OX_REQUIRE(size, mc::decodeInteger<StringLength>(m_reader, bytesRead));
+		if (size > buffLen) {
+			return ox::Error(McOutputBuffEnded);
+		}
+		// re-allocate in case too small
+		auto data = val;
+		// read the string
+		OX_RETURN_ERROR(m_reader.read(data, size));
+		data[size] = 0;
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::fieldCString(CString, char **val) noexcept {
+	if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+		// read the length
+		size_t bytesRead = 0;
+		OX_REQUIRE(size, mc::decodeInteger<StringLength>(m_reader, bytesRead));
+		// re-allocate in case too small
+		safeDelete(*val);
+		*val = new char[size + 1];
+		auto data = ox::Span{*val, size + 1};
+		// read the string
+		OX_RETURN_ERROR(m_reader.read(data.data(), size));
+		data[size] = 0;
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+constexpr Error MetalClawReaderTemplate<Reader>::fieldCString(CString, char **val, size_t buffLen) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(size, mc::decodeInteger<StringLength>(m_reader, bytesRead));
+			// re-allocate if too small
+			if (buffLen < size + 1) {
+				safeDelete(*val);
+				*val = new char[size + 1];
+				buffLen = size + 1;
+			}
+			auto data = ox::Span{*val, size + 1};
+			// read the string
+			OX_RETURN_ERROR(m_reader.read(data.data(), size));
+			data[size] = 0;
+		} else {
+			auto data = *val;
+			if (data) {
+				data[0] = 0;
+			}
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+constexpr Result<ArrayLength> MetalClawReaderTemplate<Reader>::arrayLength(CString, bool const pass) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(g, m_reader.tellg());
+			OX_REQUIRE(out, mc::decodeInteger<ArrayLength>(m_reader, bytesRead));
+			if (!pass) {
+				OX_RETURN_ERROR(m_reader.seekg(g));
+			}
+			return out;
+		}
+	}
+	return ox::Error(1);
+}
+
+template<Reader_c Reader>
+constexpr Result<StringLength> MetalClawReaderTemplate<Reader>::stringLength(CString) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			auto len = mc::decodeInteger<StringLength>(m_reader, bytesRead);
+			OX_RETURN_ERROR(m_reader.seekg(-static_cast<int64_t>(bytesRead), ox::ios_base::cur));
+			return len;
+		}
+	}
+	return 0;
+}
+
+template<Reader_c Reader>
+template<typename I>
+constexpr Error MetalClawReaderTemplate<Reader>::readInteger(I &val) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			size_t bytesRead = 0;
+			auto const result = mc::decodeInteger<I>(m_reader, bytesRead);
+			OX_RETURN_ERROR(result);
+			val = result.value;
+		} else {
+			val = 0;
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<typename T, typename CB>
+constexpr Error MetalClawReaderTemplate<Reader>::field(CString, CB cb) noexcept {
+	if (!m_unionIdx.has_value() || static_cast<size_t>(*m_unionIdx) == m_field) {
+		if (m_fieldPresence.get(static_cast<size_t>(m_field))) {
+			// read the length
+			size_t bytesRead = 0;
+			OX_REQUIRE(len, mc::decodeInteger<ArrayLength>(m_reader, bytesRead));
+			// read the list
+			auto reader = child("");
+			auto &handler = *reader.interface();
+			OX_RETURN_ERROR(handler.setTypeInfo("List", 0, {}, static_cast<size_t>(len)));
+			for (size_t i = 0; i < len; ++i) {
+				T val;
+				OX_RETURN_ERROR(handler.field("", &val));
+				OX_RETURN_ERROR(cb(i, &val));
+			}
+		}
+	}
+	++m_field;
+	return {};
+}
+
+template<Reader_c Reader>
+template<typename T>
+constexpr ox::Error MetalClawReaderTemplate<Reader>::setTypeInfo(
+		CString, int, const Vector<String>&, size_t const fields) noexcept {
+	m_fields = fields;
+	// Warning: narrow-conv
+	return m_reader.seekg(
+			static_cast<int>((fields / 8 + 1) - (fields % 8 == 0)),
+			ox::ios_base::cur);
+}
+
+template<Reader_c Reader>
+constexpr MetalClawReaderTemplate<Reader> MetalClawReaderTemplate<Reader>::child(
+		CString,
+		Optional<int> const unionIdx) noexcept {
+	return MetalClawReaderTemplate<Reader>(m_reader, unionIdx);
+}
+
+template<Reader_c Reader>
+constexpr bool MetalClawReaderTemplate<Reader>::fieldPresent(CString) const noexcept {
+	return m_fieldPresence.get(static_cast<size_t>(m_field)).value;
+}
+
+template<Reader_c Reader>
+constexpr bool MetalClawReaderTemplate<Reader>::fieldPresent(int const fieldNo) const noexcept {
+	return m_fieldPresence.get(static_cast<size_t>(fieldNo)).value;
+}
+
+template<Reader_c Reader>
+[[nodiscard]]
+constexpr int MetalClawReaderTemplate<Reader>::whichFieldPresent(CString, ModelUnion const &u) const noexcept {
+	FieldBitmapReader<Reader> p(m_reader);
+	for (auto i = 0u; i < u.fieldCount(); ++i) {
+		if (p.get(i)) {
+			return static_cast<int>(i);
+		}
+	}
+	return -1;
+}
+
+template<Reader_c Reader>
+constexpr void MetalClawReaderTemplate<Reader>::nextField() noexcept {
+	++m_field;
+}
+
+using MetalClawReader = MetalClawReaderTemplate<ox::BufferReader>;
+
+template<typename T>
+Error readMC(ox::BufferView const buff, T &val) noexcept {
+	BufferReader br(buff);
+	MetalClawReader reader(br);
+	return model(reader.interface(), &val);
+}
+
+template<typename T>
+Result<T> readMC(ox::BufferView buff) noexcept {
+	Result<T> val;
+	OX_RETURN_ERROR(readMC(buff, val.value));
+	return val;
+}
+
+extern template class ModelHandlerInterface<MetalClawReaderTemplate<BufferReader>>;
+
+}

src/mc/include/ox/mc/types.hpp

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/string.hpp>
+#include <ox/std/strops.hpp>
+#include <ox/std/types.hpp>
+
+namespace ox {
+
+using StringLength = std::size_t;
+using ArrayLength = std::size_t;
+
+}

src/mc/include/ox/mc/write.hpp

@@ -0,0 +1,401 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/model/fieldcounter.hpp>
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/bit.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/hashmap.hpp>
+#include <ox/std/optional.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/units.hpp>
+
+#include "intops.hpp"
+#include "err.hpp"
+#include "presenceindicator.hpp"
+#include "types.hpp"
+
+namespace ox {
+
+template<Writer_c Writer>
+class MetalClawWriter: public ModelHandlerBase<MetalClawWriter<Writer>, OpType::Write> {
+
+	private:
+		Vector<char, 16> m_presenceMapBuff{};
+		FieldBitmapWriter m_fieldPresence{m_presenceMapBuff};
+		int m_field{};
+		Optional<int> m_unionIdx;
+		size_t m_writerBeginP{};
+		Writer &m_writer;
+
+	public:
+		constexpr explicit MetalClawWriter(Writer &writer, Optional<int> const &unionIdx = {}) noexcept;
+
+		constexpr ~MetalClawWriter() noexcept = default;
+
+		constexpr Error field(CString, int8_t const *val) noexcept;
+		constexpr Error field(CString, int16_t const *val) noexcept;
+		constexpr Error field(CString, int32_t const *val) noexcept;
+		constexpr Error field(CString, int64_t const *val) noexcept;
+
+		constexpr Error field(CString, uint8_t const *val) noexcept;
+		constexpr Error field(CString, uint16_t const *val) noexcept;
+		constexpr Error field(CString, uint32_t const *val) noexcept;
+		constexpr Error field(CString, uint64_t const *val) noexcept;
+
+		constexpr Error field(CString, bool const *val) noexcept;
+
+		template<typename T>
+		constexpr Error field(CString, T const *val, size_t len) noexcept;
+
+		template<typename T>
+		constexpr Error field(CString name, HashMap<String, T> const *val) noexcept;
+
+		template<size_t SmallStringSize>
+		constexpr Error field(CString, BasicString<SmallStringSize> const *val) noexcept;
+
+		template<size_t L>
+		constexpr Error field(CString, IString<L> const *val) noexcept;
+
+		constexpr Error fieldCString(CString name, CString const*val, size_t buffLen) noexcept;
+
+		constexpr Error fieldCString(CString name, CString *val) noexcept;
+
+		constexpr Error fieldCString(CString name, CString const*val) noexcept;
+
+		constexpr Error fieldCString(CString name, CString val, size_t strLen) noexcept;
+
+		template<typename T>
+		constexpr Error field(CString, T const *val) noexcept;
+
+		template<typename U, bool force = false>
+		constexpr Error field(CString, UnionView<U, force> val) noexcept;
+
+		template<typename T = std::nullptr_t>
+		constexpr Error setTypeInfo(
+				CString name = T::TypeName,
+				int version = T::TypeVersion,
+		        Vector<String> const& = {},
+				size_t fields = ModelFieldCount_v<T>) noexcept;
+
+		/**
+		 * stringLength is not implemented in MetalClawWriter
+		 */
+		[[nodiscard]]
+		constexpr auto stringLength(CString) noexcept {
+			return 0;
+		}
+
+		/**
+		 * stringLength is not implemented in MetalClawWriter
+		 */
+		[[nodiscard]]
+		constexpr auto arrayLength(CString, bool = true) noexcept {
+			return 0;
+		}
+
+		constexpr Error finalize() noexcept;
+
+	private:
+		constexpr Error appendInteger(Integer_c auto val) noexcept {
+			bool fieldSet = false;
+			if (val && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+				auto mi = mc::encodeInteger(val);
+				OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(mi.data.data()), mi.length));
+				fieldSet = true;
+			}
+			OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+			++m_field;
+			return {};
+		}
+
+};
+
+extern template class ModelHandlerInterface<MetalClawWriter<BufferWriter>>;
+extern template class ModelHandlerInterface<MetalClawWriter<CharBuffWriter>>;
+
+template<Writer_c Writer>
+constexpr MetalClawWriter<Writer>::MetalClawWriter(Writer &writer, Optional<int> const &unionIdx) noexcept:
+	m_unionIdx(unionIdx),
+	m_writerBeginP(writer.tellp()),
+	m_writer(writer) {
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, int8_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, int16_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, int32_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, int64_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, uint8_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, uint16_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, uint32_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, uint64_t const *val) noexcept {
+	return appendInteger(*val);
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::field(CString, bool const *val) noexcept {
+	if (!m_unionIdx.has_value() || *m_unionIdx == m_field) {
+		OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), *val));
+	}
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<size_t SmallStringSize>
+constexpr Error MetalClawWriter<Writer>::field(CString, BasicString<SmallStringSize> const *val) noexcept {
+	bool fieldSet = false;
+	if (val->size() && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+		// write the length
+		auto const strLen = mc::encodeInteger(val->size());
+		OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(strLen.data.data()), strLen.length));
+		// write the string
+		OX_RETURN_ERROR(m_writer.write(val->c_str(), static_cast<size_t>(val->size())));
+		fieldSet = true;
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<size_t L>
+constexpr Error MetalClawWriter<Writer>::field(CString name, IString<L> const *val) noexcept {
+	return fieldCString(name, val->data(), val->size());
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::fieldCString(CString, CString const *val, size_t) noexcept {
+	bool fieldSet = false;
+	if (!m_unionIdx.has_value() || *m_unionIdx == m_field) {
+		OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+		// this strlen is tolerated because sometimes 0 gets passed to
+		// the size param, which is a lie
+		// this code should be cleaned up at some point...
+		auto const strLen = *val ? ox::strlen(*val) : 0;
+		OX_ALLOW_UNSAFE_BUFFERS_END
+		// write the length
+		auto const strLenBuff = mc::encodeInteger(strLen);
+		OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(strLenBuff.data.data()), strLenBuff.length));
+		// write the string
+		OX_RETURN_ERROR(m_writer.write(*val, static_cast<size_t>(strLen)));
+		fieldSet = true;
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::fieldCString(CString const name, CString *val) noexcept {
+	return fieldCString(name, val, {});
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::fieldCString(CString const name, CString const *val) noexcept {
+	return fieldCString(name, val, {});
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::fieldCString(CString, CString const val, size_t const strLen) noexcept {
+	bool fieldSet = false;
+	if (strLen && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+		// write the length
+		auto const strLenBuff = mc::encodeInteger(strLen);
+		OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(strLenBuff.data.data()), strLenBuff.length));
+		// write the string
+		OX_RETURN_ERROR(m_writer.write(val, static_cast<size_t>(strLen)));
+		fieldSet = true;
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<typename T>
+constexpr Error MetalClawWriter<Writer>::field(CString, T const *val) noexcept {
+	if constexpr(isVector_v<T> || isArray_v<T>) {
+		return field(nullptr, val->data(), val->size());
+	} else {
+		bool fieldSet = false;
+		if (val && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+			auto const writeIdx = m_writer.tellp();
+			MetalClawWriter writer(m_writer);
+			OX_RETURN_ERROR(model(writer.interface(), val));
+			OX_RETURN_ERROR(writer.finalize());
+			fieldSet = writeIdx != m_writer.tellp();
+		}
+		OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+		++m_field;
+		return {};
+	}
+}
+
+template<Writer_c Writer>
+template<typename U, bool force>
+constexpr Error MetalClawWriter<Writer>::field(CString, UnionView<U, force> val) noexcept {
+	bool fieldSet = false;
+	if (val.get() && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+		auto const writeIdx = m_writer.tellp();
+		MetalClawWriter writer(m_writer, Optional<int>(in_place, val.idx()));
+		OX_RETURN_ERROR(model(writer.interface(), val.get()));
+		OX_RETURN_ERROR(writer.finalize());
+		fieldSet = writeIdx != m_writer.tellp();
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<typename T>
+constexpr Error MetalClawWriter<Writer>::field(CString, T const *val, size_t const len) noexcept {
+	bool fieldSet = false;
+	if (len && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+		// write the length
+		auto const arrLen = mc::encodeInteger(len);
+		OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(arrLen.data.data()), arrLen.length));
+		auto const writeIdx = m_writer.tellp();
+		MetalClawWriter writer(m_writer);
+		OX_RETURN_ERROR(writer.interface()->template setTypeInfo<T>("List", 0, {}, static_cast<size_t>(len)));
+		// write the array
+		for (size_t i{}; i < len; ++i) {
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			OX_RETURN_ERROR(writer.interface()->field("", &val[i]));
+OX_ALLOW_UNSAFE_BUFFERS_END
+		}
+		OX_RETURN_ERROR(writer.finalize());
+		fieldSet = writeIdx != m_writer.tellp();
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<typename T>
+constexpr Error MetalClawWriter<Writer>::field(CString, HashMap<String, T> const *val) noexcept {
+	auto const &keys = val->keys();
+	auto const len = keys.size();
+	bool fieldSet = false;
+	if (len && (!m_unionIdx.has_value() || *m_unionIdx == m_field)) {
+		// write the length
+		auto const arrLen = mc::encodeInteger(len);
+		OX_RETURN_ERROR(m_writer.write(reinterpret_cast<CString>(arrLen.data.data()), arrLen.length));
+		// write map
+		MetalClawWriter writer(m_writer);
+		// double len for both key and value
+		OX_RETURN_ERROR(writer.interface()->setTypeInfo("Map", 0, {}, len * 2));
+		// this loop body needs to be in a lambda because of the potential alloca call
+		constexpr auto loopBody = [](auto &handler, auto const &key, auto const &val) -> Error {
+			auto const keyLen = key.size();
+			auto wkey = ox_malloca(keyLen + 1, char, 0);
+			memcpy(wkey.get(), key.c_str(), keyLen + 1);
+			OX_RETURN_ERROR(handler.fieldCString("", wkey.get(), keyLen));
+			OX_REQUIRE_M(value, val.at(key));
+			return handler.field("", value);
+		};
+		// write the array
+		for (size_t i{}; i < len; ++i) {
+			auto const &key = keys[i];
+			OX_RETURN_ERROR(loopBody(*writer.interface(), key, *val));
+		}
+		OX_RETURN_ERROR(writer.finalize());
+		fieldSet = true;
+	}
+	OX_RETURN_ERROR(m_fieldPresence.set(static_cast<size_t>(m_field), fieldSet));
+	++m_field;
+	return {};
+}
+
+template<Writer_c Writer>
+template<typename T>
+constexpr Error MetalClawWriter<Writer>::setTypeInfo(
+		CString,
+		int,
+		Vector<String> const&,
+		size_t const fields) noexcept {
+	auto const fieldPresenceLen = (fields - 1) / 8 + 1;
+	OX_RETURN_ERROR(m_writer.write(nullptr, fieldPresenceLen));
+	m_presenceMapBuff.resize(fieldPresenceLen);
+	m_fieldPresence.setBuffer(m_presenceMapBuff);
+	return m_fieldPresence.setFields(static_cast<int>(fields));
+}
+
+template<Writer_c Writer>
+constexpr Error MetalClawWriter<Writer>::finalize() noexcept {
+	auto const end = m_writer.tellp();
+	OX_RETURN_ERROR(m_writer.seekp(m_writerBeginP));
+	OX_RETURN_ERROR(m_writer.write(
+		m_presenceMapBuff.data(),
+		m_presenceMapBuff.size()));
+	OX_RETURN_ERROR(m_writer.seekp(end));
+	return {};
+}
+
+Result<Buffer> writeMC(Writer_c auto &writer, auto const &val) noexcept {
+	MetalClawWriter mcWriter(writer);
+	OX_RETURN_ERROR(model(mcWriter.interface(), &val));
+	OX_RETURN_ERROR(mcWriter.finalize());
+	return {};
+}
+
+Result<Buffer> writeMC(auto const &val, size_t const buffReserveSz = 2 * units::KB) noexcept {
+	Buffer buff(buffReserveSz);
+	BufferWriter bw(&buff, 0);
+	OX_RETURN_ERROR(writeMC(bw, val));
+	buff.resize(bw.tellp());
+	return buff;
+}
+
+Error writeMC(char *buff, size_t const buffLen, auto const &val, size_t *sizeOut = nullptr) noexcept {
+	CharBuffWriter bw{{buff, buffLen}};
+	OX_RETURN_ERROR(writeMC(bw, val));
+	if (sizeOut) {
+		*sizeOut = bw.tellp();
+	}
+	return {};
+}
+
+}

src/mc/src/read.cpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/reader.hpp>
+
+#include <ox/mc/read.hpp>
+
+namespace ox {
+
+template class ModelHandlerInterface<MetalClawReaderTemplate<BufferReader>>;
+
+}

src/mc/src/write.cpp

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/assert.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/memops.hpp>
+#include <ox/std/trace.hpp>
+
+#include <ox/mc/write.hpp>
+
+namespace ox {
+
+template class ModelHandlerInterface<MetalClawWriter<BufferWriter>>;
+template class ModelHandlerInterface<MetalClawWriter<CharBuffWriter>>;
+
+}

src/mc/test/CMakeLists.txt

@@ -0,0 +1,16 @@
+add_executable(
+	McTest
+		tests.cpp
+)
+
+target_link_libraries(
+	McTest
+		OxMetalClaw
+)
+
+add_test("[ox/mc] Writer" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest MetalClawWriter)
+add_test("[ox/mc] Reader" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest MetalClawReader)
+#add_test("[ox/mc] MetalClawDef" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest MetalClawDef)
+add_test("[ox/mc] MetalClawModelValue" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest MetalClawModelValue)
+add_test("[ox/mc] encodeInteger" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest encodeInteger)
+add_test("[ox/mc] decodeInteger" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/McTest decodeInteger)

src/mc/test/tests.cpp

@@ -0,0 +1,476 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#undef NDEBUG
+
+#include <iostream>
+#include <map>
+#include <ox/mc/mc.hpp>
+#include <ox/model/model.hpp>
+#include <ox/std/std.hpp>
+
+union TestUnion {
+	static constexpr auto TypeName = "TestUnion";
+	static constexpr auto TypeVersion = 1;
+	bool Bool;
+	uint32_t Int;
+	char *CString{};
+};
+
+struct TestStructNest {
+	static constexpr auto TypeName = "TestStructNest";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	uint32_t Int = 0;
+	ox::IString<32> IString = "";
+};
+
+struct TestStruct {
+	static constexpr auto TypeName = "TestStruct";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	int32_t Int = 0;
+	int32_t Int1 = 0;
+	int32_t Int2 = 0;
+	int32_t Int3 = 0;
+	int32_t Int4 = 0;
+	int32_t Int5 = 0;
+	int32_t Int6 = 0;
+	int32_t Int7 = 0;
+	int32_t Int8 = 0;
+	int unionIdx = 1;
+	TestUnion Union;
+	ox::String String;
+	ox::IString<32> IString = "";
+	uint32_t List[4] = {0, 0, 0, 0};
+	ox::Vector<uint32_t> Vector = {1, 2, 3, 4, 5};
+	ox::Vector<uint32_t> Vector2 = {1, 2, 3, 4, 5};
+	ox::HashMap<ox::String, int> Map;
+	TestStructNest EmptyStruct;
+	TestStructNest Struct;
+	constexpr ~TestStruct() noexcept {
+		if (unionIdx == 2) {
+			ox::safeDelete(Union.CString);
+		}
+	}
+};
+
+template<typename T>
+constexpr ox::Error model(T *io, ox::CommonPtrWith<TestUnion> auto *obj) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestUnion>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->fieldCString("CString", &obj->CString));
+	return ox::Error(0);
+}
+
+OX_MODEL_BEGIN(TestStructNest)
+	OX_MODEL_FIELD(Bool)
+	OX_MODEL_FIELD(Int)
+	OX_MODEL_FIELD(IString)
+OX_MODEL_END()
+
+template<typename T>
+constexpr ox::Error model(T *io, ox::CommonPtrWith<TestStruct> auto *obj) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestStruct>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->field("Int1", &obj->Int1));
+	OX_RETURN_ERROR(io->field("Int2", &obj->Int2));
+	OX_RETURN_ERROR(io->field("Int3", &obj->Int3));
+	OX_RETURN_ERROR(io->field("Int4", &obj->Int4));
+	OX_RETURN_ERROR(io->field("Int5", &obj->Int5));
+	OX_RETURN_ERROR(io->field("Int6", &obj->Int6));
+	OX_RETURN_ERROR(io->field("Int7", &obj->Int7));
+	OX_RETURN_ERROR(io->field("Int8", &obj->Int8));
+	OX_RETURN_ERROR(io->field("unionIdx", &obj->unionIdx));
+	if constexpr(T::opType() == ox::OpType::Reflect) {
+		OX_RETURN_ERROR(io->field("Union", ox::UnionView{&obj->Union, 0}));
+	} else {
+		OX_RETURN_ERROR(io->field("Union", ox::UnionView{&obj->Union, obj->unionIdx}));
+	}
+	OX_RETURN_ERROR(io->field("String", &obj->String));
+	OX_RETURN_ERROR(io->field("IString", &obj->IString));
+	OX_RETURN_ERROR(io->field("List", obj->List, 4));
+	OX_RETURN_ERROR(io->field("Vector", &obj->Vector));
+	OX_RETURN_ERROR(io->field("Vector2", &obj->Vector2));
+	OX_RETURN_ERROR(io->field("Map", &obj->Map));
+	OX_RETURN_ERROR(io->field("Struct", &obj->Struct));
+	OX_RETURN_ERROR(io->field("EmptyStruct", &obj->EmptyStruct));
+	return ox::Error(0);
+}
+
+std::map<ox::StringView, ox::Error(*)()> tests = {
+	{
+		{
+			"MetalClawWriter",
+			[] {
+				// This test doesn't confirm much, but it does show that the writer
+				// doesn't segfault
+				ox::Array<char, 1024> buff;
+				TestStruct ts;
+				OX_RETURN_ERROR(ox::writeMC(buff.data(), buff.size(), ts));
+				OX_RETURN_ERROR(ox::writeMC(ts));
+				return ox::Error(0);
+			}
+		},
+
+		{
+			"MetalClawReader",
+			[] {
+				// setup for tests
+				TestStruct testIn, testOut;
+				testIn.Bool = true;
+				testIn.Int = 42;
+				testIn.IString = "Test String 1";
+				testIn.String = "Test String 2";
+				testIn.Vector = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, };
+				testIn.Vector2 = {};
+				testIn.List[0] = 1;
+				testIn.List[1] = 2;
+				testIn.List[2] = 3;
+				testIn.List[3] = 4;
+				testIn.Struct.Bool = true;
+				testIn.Struct.Int = 300;
+				testIn.Struct.IString = "Test String 3";
+				testIn.unionIdx = 1;
+				testIn.Union.Int = 93;
+				// run tests
+				const auto [buff, err] = ox::writeMC(testIn);
+				oxAssert(err, "writeMC failed");
+				oxAssert(ox::readMC(buff, testOut), "readMC failed");
+				//std::cout << testIn.Union.Int << "|" << testOut.Union.Int << "|\n";
+				oxAssert(testIn.Bool                == testOut.Bool,                "Bool value mismatch");
+				oxAssert(testIn.Int                 == testOut.Int,                 "Int value mismatch");
+				oxAssert(testIn.Int1                == testOut.Int1,                "Int1 value mismatch");
+				oxAssert(testIn.Int2                == testOut.Int2,                "Int2 value mismatch");
+				oxAssert(testIn.Int3                == testOut.Int3,                "Int3 value mismatch");
+				oxAssert(testIn.Int4                == testOut.Int4,                "Int4 value mismatch");
+				oxAssert(testIn.Int5                == testOut.Int5,                "Int5 value mismatch");
+				oxAssert(testIn.Int6                == testOut.Int6,                "Int6 value mismatch");
+				oxAssert(testIn.Int7                == testOut.Int7,                "Int7 value mismatch");
+				oxAssert(testIn.Int8                == testOut.Int8,                "Int8 value mismatch");
+				oxAssert(testIn.Union.Int           == testOut.Union.Int,           "Union.Int value mismatch");
+				oxAssert(testIn.String              == testOut.String,              "String value mismatch");
+				ox::expect(testIn.IString,               testOut.IString);
+				oxAssert(testIn.List[0]             == testOut.List[0],             "List[0] value mismatch");
+				oxAssert(testIn.List[1]             == testOut.List[1],             "List[1] value mismatch");
+				oxAssert(testIn.List[2]             == testOut.List[2],             "List[2] value mismatch");
+				oxAssert(testIn.List[3]             == testOut.List[3],             "List[3] value mismatch");
+				oxAssert(testIn.Vector.size()       == testOut.Vector.size(),       "Vector size mismatch");
+				for (auto i = 0u; i < testIn.Vector.size(); ++i) {
+					oxAssert(testIn.Vector[i]        == testOut.Vector[i],           ox::sfmt("Vector[{}] value mismatch", i));
+				}
+				oxAssert(testIn.Vector2.size()      == testOut.Vector2.size(),      "Vector2 size mismatch");
+				oxAssert(testIn.Map["asdf"]         == testOut.Map["asdf"],         "Map[\"asdf\"] value mismatch");
+				oxAssert(testIn.Map["aoeu"]         == testOut.Map["aoeu"],         "Map[\"aoeu\"] value mismatch");
+				oxAssert(testIn.EmptyStruct.Bool    == testOut.EmptyStruct.Bool,    "EmptyStruct.Bool value mismatch");
+				oxAssert(testIn.EmptyStruct.Int     == testOut.EmptyStruct.Int,     "EmptyStruct.Int value mismatch");
+				oxAssert(testIn.EmptyStruct.IString == testOut.EmptyStruct.IString, "EmptyStruct.IString value mismatch");
+				oxAssert(testIn.Struct.Int          == testOut.Struct.Int,          "Struct.Int value mismatch");
+				oxAssert(testIn.Struct.IString      == testOut.Struct.IString,      "Struct.IString value mismatch");
+				oxAssert(testIn.Struct.Bool         == testOut.Struct.Bool,         "Struct.Bool value mismatch");
+				return ox::Error(0);
+			}
+		},
+
+		{
+			"encodeInteger",
+			[] {
+				using ox::MaxValue;
+				using ox::mc::McInt;
+				using ox::mc::encodeInteger;
+				static constexpr auto check = [](McInt val, const ox::Vector<uint8_t, 9> &expected) {
+					if (val.length != expected.size()) {
+						std::cout << "val.length: " << val.length << ", expected: " << expected.size() << '\n';
+						return ox::Error(1);
+					}
+					for (std::size_t i = 0; i < expected.size(); i++) {
+						if (expected[i] != val.data[i]) {
+							std::cout << "decoded: " << static_cast<uint32_t>(val.data[i]) << ", expected: " << static_cast<uint32_t>(expected[i]) << '\n';
+							std::cout << "decoded: " << i << ": " << static_cast<uint32_t>(val.data[i]) << '\n';
+							return ox::Error(1);
+						}
+					}
+					return ox::Error(0);
+				};
+				constexpr auto check64 = [](McInt val, auto expected) {
+					if (val.length != 9) {
+						std::cout << "val.length: " << val.length << '\n';
+						return ox::Error(1);
+					}
+					ox::LittleEndian<decltype(expected)> decoded = *reinterpret_cast<decltype(expected)*>(&val.data[1]);
+					if (expected != decoded) {
+						std::cout << "decoded: " << decoded << ", expected: " << expected << '\n';
+						return ox::Error(1);
+					}
+					return ox::Error(0);
+				};
+				// signed positive
+				oxAssert(check(encodeInteger(int64_t(1)), {0b000'0001'0}), "Encode 1 fail");
+				oxAssert(check(encodeInteger(int64_t(2)), {0b000'0010'0}), "Encode 2 fail");
+				oxAssert(check(encodeInteger(int64_t(3)), {0b000'0011'0}), "Encode 3 fail");
+				oxAssert(check(encodeInteger(int64_t(4)), {0b000'0100'0}), "Encode 4 fail");
+				oxAssert(check(encodeInteger(int64_t(64)), {0b00'0000'01, 0b1}), "Encode 64 fail");
+				oxAssert(check(encodeInteger(int64_t(128)), {0b00'0000'01, 0b10}), "Encode 128 fail");
+				oxAssert(check(encodeInteger(int64_t(129)), {0b00'0001'01, 0b10}), "Encode 129 fail");
+				oxAssert(check(encodeInteger(int64_t(130)), {0b00'0010'01, 0b10}), "Encode 130 fail");
+				oxAssert(check(encodeInteger(int64_t(131)), {0b00'0011'01, 0b10}), "Encode 131 fail");
+				// signed negative
+				oxAssert(check(encodeInteger(  int64_t(-1)), {0b111'1111'0}), "Encode -1 fail");
+				oxAssert(check(encodeInteger(  int64_t(-2)), {0b111'1110'0}), "Encode -2 fail");
+				oxAssert(check(encodeInteger(  int64_t(-3)), {0b111'1101'0}), "Encode -3 fail");
+				oxAssert(check(encodeInteger(  int64_t(-4)), {0b111'1100'0}), "Encode -4 fail");
+				oxAssert(check(encodeInteger( int64_t(-64)), {0b100'0000'0}), "Encode -64 fail");
+				oxAssert(check(encodeInteger(int64_t(-128)), {0b00'0000'01, 0b11'1111'10}), "Encode -128 fail");
+				oxAssert(check(encodeInteger(int64_t(-129)), {0b11'1111'01, 0b11'1111'01}), "Encode -129 fail");
+				oxAssert(check(encodeInteger(int64_t(-130)), {0b11'1110'01, 0b11'1111'01}), "Encode -130 fail");
+				oxAssert(check(encodeInteger(int64_t(-131)), {0b11'1101'01, 0b11'1111'01}), "Encode -131 fail");
+				// unsigned
+				oxAssert(check(encodeInteger(uint32_t(0xffffffff)), {0b11101111, 255, 255, 255, 0b00011111}), "Encode 0xffffffff fail");
+				oxAssert(check(encodeInteger(uint64_t(1)), {0b0010}), "Encode 1 fail");
+				oxAssert(check(encodeInteger(uint64_t(2)), {0b0100}), "Encode 2 fail");
+				oxAssert(check(encodeInteger(uint64_t(3)), {0b0110}), "Encode 3 fail");
+				oxAssert(check(encodeInteger(uint64_t(4)), {0b1000}), "Encode 4 fail");
+				oxAssert(check(encodeInteger(uint64_t(64)), {0b1000'000'0}), "Encode 4 fail");
+				oxAssert(check(encodeInteger(uint64_t(128)), {0b0001, 0b10}), "Encode 128 fail");
+				oxAssert(check(encodeInteger(uint64_t(129)), {0b0101, 0b10}), "Encode 129 fail");
+				oxAssert(check(encodeInteger(uint64_t(130)), {0b1001, 0b10}), "Encode 130 fail");
+				oxAssert(check(encodeInteger(uint64_t(131)), {0b1101, 0b10}), "Encode 131 fail");
+				// Signed check needs lambda templates to run correctly without
+				// code deduplication
+				oxAssert(check64(encodeInteger(MaxValue<int64_t>), MaxValue<int64_t>), "Encode MaxValue<int64_t> fail");
+				oxAssert(check64(encodeInteger(MaxValue<uint64_t>), MaxValue<uint64_t>), "Encode MaxValue<uint64_t> fail");
+				return ox::Error(0);
+			}
+		},
+
+		{
+			"decodeInteger",
+			[] {
+				using ox::MaxValue;
+				using ox::mc::McInt;
+				using ox::mc::encodeInteger;
+				using ox::mc::decodeInteger;
+				static constexpr auto check = [](auto val) {
+					auto result = decodeInteger<decltype(val)>(encodeInteger(val));
+					OX_RETURN_ERROR(result.error);
+					if (result.value != val) {
+						std::cout << "Bad value: " << result.value << ", expected: " << val << '\n';
+						return ox::Error(1);
+					}
+					return ox::Error(0);
+				};
+				oxAssert(check(uint32_t(14)), "Decode of 14 failed.");
+				oxAssert(check(int8_t(-1)), "Decode of -1 failed.");
+				oxAssert(check(int16_t(-1)), "Decode of -1 failed.");
+				oxAssert(check(int32_t(-1)), "Decode of -1 failed.");
+				oxAssert(check(int64_t(-1)), "Decode of -1 failed.");
+				oxAssert(check(int64_t(-2)), "Decode of -2 failed.");
+				oxAssert(check(int64_t(-127)), "Decode of -127 failed.");
+				oxAssert(check(int64_t(-128)), "Decode of -128 failed.");
+				oxAssert(check(int64_t(-129)), "Decode of -129 failed.");
+				oxAssert(check(int64_t(-129000)), "Decode of -129000 failed.");
+				oxAssert(check(int64_t(1)), "Decode of 1 failed.");
+				oxAssert(check(int64_t(2)), "Decode of 2 failed.");
+				oxAssert(check(int64_t(42)), "Decode of 42 failed.");
+				oxAssert(check(int64_t(130)), "Decode of 130 failed.");
+				oxAssert(check(int64_t(131)), "Decode of 131 failed.");
+				oxAssert(check(int64_t(131000)), "Decode of 131000 failed.");
+				oxAssert(check(uint64_t(1)), "Decode of 1 failed.");
+				oxAssert(check(uint64_t(2)), "Decode of 2 failed.");
+				oxAssert(check(uint64_t(42)), "Decode of 42 failed.");
+				oxAssert(check(uint64_t(130)), "Decode of 130 failed.");
+				oxAssert(check(uint64_t(131)), "Decode of 131 failed.");
+				oxAssert(check(0xffffffff), "Decode of 0xffffffff failed.");
+				oxAssert(check(0xffffffffffff), "Decode of 0xffffffffffff failed.");
+				oxAssert(check(0xffffffffffffffff), "Decode of U64 max failed.");
+				return ox::Error(0);
+			}
+		},
+
+
+		{
+			"MetalClawModelValue",
+			[] {
+				static constexpr size_t dataBuffLen = ox::units::MB;
+				ox::Buffer dataBuff(dataBuffLen);
+				TestStruct testIn;
+				testIn.Bool = true;
+				testIn.Int = 42;
+				testIn.IString = "Test String 1";
+				testIn.List[0] = 1;
+				testIn.List[1] = 2;
+				testIn.List[2] = 3;
+				testIn.List[3] = 4;
+				testIn.Struct.Bool = true;
+				testIn.Struct.Int = 300;
+				testIn.Struct.IString = "Test String 2";
+				testIn.unionIdx = 1;
+				testIn.Union.Int = 93;
+				oxAssert(ox::writeMC(dataBuff.data(), dataBuff.size(), testIn), "Data generation failed");
+				ox::TypeStore typeStore;
+				const auto [type, typeErr] = ox::buildTypeDef(typeStore, testIn);
+				oxAssert(typeErr, "Descriptor write failed");
+				ox::ModelObject testOut;
+				OX_RETURN_ERROR(testOut.setType(type));
+				oxAssert(ox::readMC(dataBuff, testOut), "Data read failed");
+				oxAssert(testOut.at("Int").unwrap()->get<int>() == testIn.Int, "testOut.Int failed");
+				oxAssert(testOut.at("Bool").unwrap()->get<bool>() == testIn.Bool, "testOut.Bool failed");
+				oxAssert(testOut.at("IString").unwrap()->get<ox::String>() == testIn.IString.c_str(), "testOut.String failed");
+				oxAssert(testOut.at("String").unwrap()->get<ox::String>() == testIn.String, "testOut.String failed");
+				auto &testOutStruct = testOut.at("Struct").unwrap()->get<ox::ModelObject>();
+				auto &testOutUnion = testOut.at("Union").unwrap()->get<ox::ModelUnion>();
+				auto &testOutList = testOut.at("List").unwrap()->get<ox::ModelValueVector>();
+				auto testOutStructCopy = testOut.at("Struct").unwrap()->get<ox::ModelObject>();
+				auto testOutUnionCopy = testOut.at("Union").unwrap()->get<ox::ModelUnion>();
+				auto testOutListCopy = testOut.at("List").unwrap()->get<ox::ModelValueVector>();
+				oxAssert(testOutStruct.typeName() == TestStructNest::TypeName, "ModelObject TypeName failed");
+				oxAssert(testOutStruct.typeVersion() == TestStructNest::TypeVersion, "ModelObject TypeVersion failed");
+				oxAssert(testOutStruct.at("Bool").unwrap()->get<bool>() == testIn.Struct.Bool, "testOut.Struct.Bool failed");
+				oxAssert(testOutStruct.at("IString").unwrap()->get<ox::String>() == testIn.Struct.IString.c_str(), "testOut.Struct.IString failed");
+				oxAssert(testOut.at("unionIdx").unwrap()->get<int>() == testIn.unionIdx, "testOut.unionIdx failed");
+				oxAssert(testOutUnion.unionIdx() == testIn.unionIdx, "testOut.Union idx wrong");
+				oxAssert(testOutUnion.at("Int").unwrap()->get<uint32_t>() == testIn.Union.Int, "testOut.Union.Int failed");
+				oxAssert(testOutList[0].get<uint32_t>() == testIn.List[0], "testOut.List[0] failed");
+				oxAssert(testOutList[1].get<uint32_t>() == testIn.List[1], "testOut.Struct.List[1] failed");
+				oxAssert(testOutStructCopy.at("Bool").unwrap()->get<bool>() == testIn.Struct.Bool, "testOut.Struct.Bool (copy) failed");
+				oxAssert(testOutStructCopy.at("IString").unwrap()->get<ox::String>() == testIn.Struct.IString.c_str(), "testOut.Struct.IString (copy) failed");
+				oxAssert(testOutListCopy[0].get<uint32_t>() == testIn.List[0], "testOut.Struct.List[0] (copy) failed");
+				oxAssert(testOutListCopy[1].get<uint32_t>() == testIn.List[1], "testOut.Struct.List[1] (copy) failed");
+				return ox::Error(0);
+			}
+		},
+
+		{
+			"MetalClawDef",
+			[] {
+				 //constexpr size_t descBuffLen = 1024;
+				 //uint8_t descBuff[descBuffLen];
+				 static constexpr size_t dataBuffLen = ox::units::MB;
+				 char dataBuff[dataBuffLen];
+				 TestStruct testIn, testOut;
+				 testIn.Bool = true;
+				 testIn.Int = 42;
+				 testIn.IString = "Test String 1";
+				 testIn.List[0] = 1;
+				 testIn.List[1] = 2;
+				 testIn.List[2] = 3;
+				 testIn.List[3] = 4;
+				 testIn.Struct.Bool = false;
+				 testIn.Struct.Int = 300;
+				 testIn.Struct.IString = "Test String 2";
+				 oxAssert(ox::writeMC(dataBuff, dataBuffLen, testIn), "Data generation failed");
+				 ox::TypeStore typeStore;
+				 const auto [type, typeErr] = ox::buildTypeDef(typeStore, testIn);
+				 oxAssert(typeErr, "Descriptor write failed");
+				 ox::BufferReader br({dataBuff, dataBuffLen});
+				 OX_RETURN_ERROR(ox::walkModel<ox::MetalClawReader>(type, br,
+					[](const ox::Vector<ox::FieldName>&, const ox::Vector<ox::String>&, const ox::DescriptorField &f, ox::MetalClawReader *rdr) -> ox::Error {
+						//std::cout << f.fieldName.c_str() << '\n';
+						auto fieldName = f.fieldName.c_str();
+						switch (f.type->primitiveType) {
+							case ox::PrimitiveType::UnsignedInteger:
+							  std::cout << fieldName << ":\tuint" << f.type->length * 8 << "_t:\t";
+							  switch (f.type->length) {
+									case 1: {
+										uint8_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 2: {
+										uint16_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 4: {
+										uint32_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 8: {
+										uint64_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+								}
+								std::cout << '\n';
+								break;
+							case ox::PrimitiveType::SignedInteger:
+								std::cout << fieldName << ":\tint" << f.type->length * 8 << "_t:\t";
+								switch (f.type->length) {
+									case 1: {
+										int8_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 2: {
+										int16_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 4: {
+										int32_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+									case 8: {
+										int64_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										std::cout << i;
+										break;
+									}
+								}
+								std::cout << '\n';
+								break;
+							case ox::PrimitiveType::Bool: {
+								bool i = {};
+								oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+								std::cout << fieldName << ":\t" << "bool:\t\t" << (i ? "true" : "false") << '\n';
+								break;
+							}
+							case ox::PrimitiveType::String: {
+								ox::String s;
+								//std::cout << rdr->stringLength() << '\n';
+								oxAssert(rdr->field(fieldName, &s), "Walking model failed.");
+								oxOutf("{}:\tstring:\t\t{}\n", fieldName, s);
+								break;
+							}
+							case ox::PrimitiveType::Struct:
+								break;
+							case ox::PrimitiveType::Union:
+								break;
+						}
+						return ox::Error(0);
+					}
+				));
+				return ox::Error(0);
+			}
+		},
+	}
+};
+
+int main(int argc, const char **args) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+	}
+	auto const testName = args[1];
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/model/CMakeLists.txt

@@ -0,0 +1,45 @@
+add_library(
+	OxModel
+		src/desctypes.cpp
+		src/descwrite.cpp
+		src/modelvalue.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxModel PRIVATE -Wconversion)
+	target_compile_options(OxModel PRIVATE -Wsign-conversion)
+endif()
+
+target_link_libraries(
+	OxModel PUBLIC
+		OxStd
+)
+
+if(NOT OX_BARE_METAL)
+	set_property(
+		TARGET
+			OxModel
+		PROPERTY
+			POSITION_INDEPENDENT_CODE ON
+	)
+endif()
+
+target_link_libraries(
+	OxModel PUBLIC
+		OxStd
+)
+
+target_include_directories(
+	OxModel PUBLIC
+		include
+)
+
+install(
+	TARGETS OxModel
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/model/definition-language.txt

@@ -0,0 +1,7 @@
+<Type>      : <TypeName><FieldList>
+<FieldList> : <FieldList> | <FieldList><Field>
+<Field>     : <FieldType><TypeID><FieldName>
+<TypeID>    : <TypeName> | <TypeName><Type>
+<TypeName>  : <string>
+<FieldType> : <0: single> | <1: list>
+<FieldName> : <string>

src/model/include/ox/model/def.hpp

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/concepts.hpp>
+
+// oxModelFwdDecl is necessary because Apple-Clang is broken...
+#define OX_MODEL_FWD_DECL(modelName) constexpr ox::Error model(auto *io, ox::CommonPtrWith<modelName> auto *o) noexcept
+#define OX_MODEL_BEGIN(modelName) constexpr ox::Error model(auto *io, [[maybe_unused]] ox::CommonPtrWith<modelName> auto *o) noexcept { OX_RETURN_ERROR(io->template setTypeInfo<modelName>());
+#define OX_MODEL_END() return {}; }
+#define OX_MODEL_FIELD(fieldName) OX_RETURN_ERROR(io->field(#fieldName, &o->fieldName));
+#define OX_MODEL_FIELD_RENAME(objFieldName, serFieldName) OX_RETURN_ERROR(io->field(#serFieldName, &o->objFieldName));
+#define OX_MODEL_FRIEND(modelName) friend constexpr ox::Error model(auto *io, ox::CommonPtrWith<modelName> auto *o) noexcept

src/model/include/ox/model/definition-language.txt

@@ -0,0 +1,7 @@
+<Type>      : <TypeName><FieldList>
+<FieldList> : <FieldList> | <FieldList><Field>
+<Field>     : <FieldType><TypeID><FieldName>
+<TypeID>    : <TypeName> | <TypeName><Type>
+<TypeName>  : <string>
+<FieldType> : <0: single> | <1: list>
+<FieldName> : <string>

src/model/include/ox/model/descread.hpp

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "typestore.hpp"
+#include "desctypes.hpp"
+
+namespace ox {
+
+template<typename ReaderBase>
+class TypeDescReader: public ReaderBase {
+	private:
+		TypeStore m_typeStore;
+
+	public:
+		constexpr TypeDescReader(const uint8_t *buff, std::size_t buffLen) noexcept;
+
+		[[nodiscard]]
+		constexpr const auto &typeStore() const noexcept;
+
+};
+
+template<typename ReaderBase>
+constexpr TypeDescReader<ReaderBase>::TypeDescReader(const uint8_t *buff, std::size_t buffLen) noexcept:
+	ReaderBase(buff, buffLen) {
+}
+
+template<typename ReaderBase>
+constexpr const auto &TypeDescReader<ReaderBase>::typeStore() const noexcept {
+	return m_typeStore;
+}
+
+template<typename ReaderBase, typename T>
+constexpr int readMCDef(const uint8_t *buff, std::size_t buffLen, T *val) noexcept {
+	TypeDescReader<ReaderBase> reader(buff, buffLen);
+	return model(&reader, val);
+}
+
+}

src/model/include/ox/model/desctypes.hpp

@@ -0,0 +1,251 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/bit.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/fmt.hpp>
+#include <ox/std/hashmap.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/typetraits.hpp>
+#include <ox/std/vector.hpp>
+
+#include "optype.hpp"
+#include "types.hpp"
+#include "typenamecatcher.hpp"
+
+namespace ox {
+
+using FieldName = String;
+
+using TypeParamPack = Vector<String>;
+
+template<typename T>
+constexpr auto buildTypeId() noexcept {
+	constexpr auto name = requireModelTypeName<T>();
+	constexpr auto version = requireModelTypeVersion<T>();
+	return ox::sfmt("{};{}", name, version);
+}
+
+static constexpr auto buildTypeId(
+		StringViewCR name, int version,
+		const TypeParamPack &typeParams = {}) noexcept {
+	String tp;
+	if (!typeParams.empty()) {
+		tp = "#";
+		for (const auto &p : typeParams) {
+			tp += p + ",";
+		}
+		tp.resize(tp.size() - 1);
+		tp += "#";
+	}
+	return ox::sfmt("{}{};{}", name, tp, version);
+}
+
+enum class PrimitiveType: uint8_t {
+	UnsignedInteger = 0,
+	SignedInteger = 1,
+	Bool = 2,
+	// Float = 3, reserved, but not implemented
+	String = 4,
+	Struct = 5,
+	Union = 6,
+};
+
+struct Subscript {
+	static constexpr auto TypeName = "net.drinkingtea.ox.Subscript";
+	static constexpr auto TypeVersion = 1;
+	enum class SubscriptType: uint32_t {
+		None        = 0,
+		Ptr         = 1,
+		PtrArray    = 2,
+		InlineArray = 3,
+		Vector      = 4,
+	};
+	SubscriptType subscriptType = SubscriptType::None;
+	uint64_t length = 0;
+	uint64_t smallSzLen = 0;
+};
+
+template<typename T>
+constexpr Error model(T *io, CommonPtrWith<Subscript> auto *type) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<Subscript>());
+	if constexpr(T::opType() == OpType::Reflect) {
+		uint32_t st = 0;
+		OX_RETURN_ERROR(io->field("subscriptType", &st));
+	} else if constexpr(T::opType() == OpType::Write) {
+		auto pt = type ? static_cast<uint8_t>(type->subscriptType) : 0;
+		OX_RETURN_ERROR(io->field("subscriptType", &pt));
+	} else {
+		auto pt = type ? static_cast<uint32_t>(type->subscriptType) : 0;
+		OX_RETURN_ERROR(io->field("subscriptType", &pt));
+		type->subscriptType = static_cast<Subscript::SubscriptType>(pt);
+	}
+	OX_RETURN_ERROR(io->field("length", &type->length));
+	OX_RETURN_ERROR(io->field("smallSzLen", &type->smallSzLen));
+	return {};
+}
+
+using SubscriptStack = Vector<Subscript, 3>;
+
+struct DescriptorField {
+	// order of fields matters
+
+	static constexpr auto TypeName = "net.drinkingtea.ox.DescriptorField";
+	static constexpr auto TypeVersion = 3;
+
+	// do not serialize type
+	const struct DescriptorType *type = nullptr;
+	String fieldName;
+	int subscriptLevels = 0;
+	SubscriptStack subscriptStack;
+	String typeId; // gives reference to type for lookup if type is null
+
+	constexpr DescriptorField() noexcept = default;
+
+	constexpr DescriptorField(const DescriptorType *pType, String pFieldName,
+	                          int pSubscriptLevels,
+	                          SubscriptStack pSubscriptType,
+	                          String pTypeId) noexcept:
+		type(pType),
+		fieldName(std::move(pFieldName)),
+		subscriptLevels(pSubscriptLevels),
+		subscriptStack(std::move(pSubscriptType)),
+		typeId(std::move(pTypeId)) {
+		oxAssert(subscriptLevels <= static_cast<int>(subscriptStack.size()), "Subscript level mismatch");
+	}
+
+	constexpr DescriptorField(const DescriptorField &other) noexcept:
+		type(other.type),
+		fieldName(other.fieldName),
+		subscriptLevels(other.subscriptLevels),
+		subscriptStack(other.subscriptStack),
+		typeId(other.typeId) {
+	}
+
+	constexpr DescriptorField(DescriptorField &&other) noexcept:
+		type(other.type),
+		fieldName(std::move(other.fieldName)),
+		subscriptLevels(other.subscriptLevels),
+		subscriptStack(std::move(other.subscriptStack)),
+		typeId(std::move(other.typeId)) {
+		other.type = {};
+		other.subscriptLevels = {};
+		other.subscriptStack = {};
+	}
+
+	constexpr ~DescriptorField() noexcept = default;
+
+	constexpr DescriptorField &operator=(const DescriptorField &other) noexcept = delete;
+
+	constexpr DescriptorField &operator=(DescriptorField &&other) noexcept = delete;
+
+};
+
+using FieldList = Vector<DescriptorField>;
+
+struct DescriptorType {
+
+	static constexpr auto TypeName = "net.drinkingtea.ox.TypeDescriptor";
+	static constexpr auto TypeVersion = 1;
+
+	String typeName;
+	int typeVersion = 0;
+	PrimitiveType primitiveType = PrimitiveType::UnsignedInteger;
+	TypeParamPack typeParams;
+	// fieldList only applies to structs and unions
+	FieldList fieldList;
+	// - number of bytes for integer and float types
+	// - number of fields for structs and lists
+	int64_t length = 0;
+	bool preloadable = false;
+
+	constexpr DescriptorType() noexcept = default;
+
+	constexpr explicit DescriptorType(String tn, int typeVersion, PrimitiveType t, TypeParamPack pTypeParams) noexcept:
+		typeName(std::move(tn)),
+		typeVersion(typeVersion),
+		primitiveType(t),
+		typeParams(std::move(pTypeParams)) {
+	}
+
+};
+
+[[nodiscard]]
+constexpr auto buildTypeId(const DescriptorType &t) noexcept {
+	return buildTypeId(t.typeName, t.typeVersion, t.typeParams);
+}
+
+template<typename T>
+constexpr Error model(T *io, CommonPtrWith<DescriptorType> auto *type) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<DescriptorType>());
+	OX_RETURN_ERROR(io->field("typeName", &type->typeName));
+	OX_RETURN_ERROR(io->field("typeVersion", &type->typeVersion));
+	if constexpr(T::opType() == OpType::Reflect) {
+		uint8_t pt = 0;
+		OX_RETURN_ERROR(io->field("primitiveType", &pt));
+	} else if constexpr(T::opType() == OpType::Write) {
+		auto pt = type ? static_cast<uint8_t>(type->primitiveType) : 0;
+		OX_RETURN_ERROR(io->field("primitiveType", &pt));
+	} else {
+		auto pt = type ? static_cast<uint8_t>(type->primitiveType) : 0;
+		OX_RETURN_ERROR(io->field("primitiveType", &pt));
+		type->primitiveType = static_cast<PrimitiveType>(pt);
+	}
+	OX_RETURN_ERROR(io->field("typeParams", &type->typeParams));
+	OX_RETURN_ERROR(io->field("fieldList", &type->fieldList));
+	OX_RETURN_ERROR(io->field("length", &type->length));
+	OX_RETURN_ERROR(io->field("preloadable", &type->preloadable));
+	return {};
+}
+
+template<typename T>
+constexpr Error model(T *io, CommonPtrWith<DescriptorField> auto *field) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<DescriptorField>());
+	OX_RETURN_ERROR(io->field("typeId", &field->typeId));
+	OX_RETURN_ERROR(io->field("fieldName", &field->fieldName));
+	OX_RETURN_ERROR(io->field("subscriptLevels", &field->subscriptLevels));
+	OX_RETURN_ERROR(io->field("subscriptStack", &field->subscriptStack));
+	// defaultValue is unused now, but leave placeholder for backwards compatibility
+	int defaultValue = 0;
+	OX_RETURN_ERROR(io->field("defaultValue", &defaultValue));
+	return {};
+}
+
+template<typename ReaderBase>
+class TypeDescReader;
+
+#if 0 // unused right now
+template<typename T>
+constexpr Error model(TypeDescReader<T> *io, CommonPtrWith<DescriptorField> auto *field) noexcept {
+	io->template setTypeInfo<DescriptorField>();
+	oxReturnError(io->field("typeName", &field->typeName));
+	oxReturnError(io->field("typeVersion", &field->typeVersion));
+	auto &typeStore = io->typeStore();
+	auto &[type, err] = typeStore->at(field->typeName).value;
+	oxReturnError(err);
+	field->type = type.get();
+	oxReturnError(io->field("fieldName", &field->fieldName));
+	oxReturnError(io->field("subscriptLevels", &field->subscriptLevels));
+	if constexpr(T::opType() != ox::OpType::Reflect) {
+		auto subscriptStack = static_cast<uint32_t>(field->subscriptStack);
+		oxReturnError(io->field("subscriptStack", &subscriptStack));
+		field->subscriptStack = static_cast<DescriptorField::SubscriptType>(subscriptStack);
+	} else {
+		oxReturnError(io->field("subscriptStack", &field->subscriptStack));
+	}
+	// defaultValue is unused now, but placeholder for backwards compatibility
+	int defaultValue = 0;
+	oxReturnError(io->field("defaultValue", &defaultValue));
+	return {};
+}
+#endif
+
+}

src/model/include/ox/model/descwrite.hpp

@@ -0,0 +1,404 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/byteswap.hpp>
+#include <ox/std/istring.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/vector.hpp>
+
+#include "desctypes.hpp"
+#include "fieldcounter.hpp"
+#include "metadata.hpp"
+#include "modelhandleradaptor.hpp"
+#include "optype.hpp"
+#include "typenamecatcher.hpp"
+#include "types.hpp"
+#include "typestore.hpp"
+
+namespace ox {
+
+namespace detail {
+
+template<typename T>
+constexpr int indirectionLevels_v = 0;
+
+template<typename T>
+constexpr int indirectionLevels_v<T*> = 1 + indirectionLevels_v<T>;
+
+template<typename T, std::size_t sz>
+constexpr int indirectionLevels_v<T[sz]> = 1 + indirectionLevels_v<T>;
+
+template<typename T, std::size_t SmallVecSz>
+constexpr int indirectionLevels_v<::ox::Vector<T, SmallVecSz>> = 1 + indirectionLevels_v<T>;
+
+template<typename T>
+constexpr auto buildSubscriptStack(const T*, SubscriptStack*) noexcept {
+}
+
+template<typename T>
+constexpr auto buildSubscriptStack(const T**, SubscriptStack *s) noexcept {
+	s->push_back({.subscriptType = Subscript::SubscriptType::Ptr});
+}
+
+template<typename T>
+constexpr auto buildSubscriptStack(const UPtr<T>*, SubscriptStack *s) noexcept {
+	s->push_back({.subscriptType = Subscript::SubscriptType::Ptr});
+}
+
+template<typename T, std::size_t sz>
+constexpr auto buildSubscriptStack(const Array<T, sz>*, SubscriptStack *s) noexcept {
+	s->push_back({.subscriptType = Subscript::SubscriptType::InlineArray, .length = sz});
+	buildSubscriptStack(static_cast<T*>(nullptr), s);
+}
+
+template<typename T, std::size_t SmallVecSz>
+constexpr auto buildSubscriptStack(const Vector<T, SmallVecSz>*, SubscriptStack *s) noexcept {
+	s->push_back({
+		.subscriptType = Subscript::SubscriptType::Vector,
+		.smallSzLen = SmallVecSz,
+	});
+	buildSubscriptStack(static_cast<T*>(nullptr), s);
+}
+
+template<typename T>
+constexpr auto buildSubscriptStack(const T*) {
+	SubscriptStack s;
+	buildSubscriptStack(static_cast<const T*>(nullptr), &s);
+	return s;
+}
+
+}
+
+class TypeDescWriter {
+
+	private:
+		TypeStore *m_typeStore = nullptr;
+		DescriptorType *m_type = nullptr;
+
+	public:
+		explicit constexpr TypeDescWriter(TypeStore *typeStore = nullptr) noexcept;
+
+		constexpr ~TypeDescWriter() noexcept = default;
+
+		template<typename T = std::nullptr_t>
+		constexpr ox::Error setTypeInfo(StringViewCR name = T::TypeName,
+		                                int version = T::TypeVersion,
+		                                const TypeParamPack &typeParams = {},
+		                                std::size_t fields = ModelFieldCount_v<T>) noexcept;
+
+		template<typename T>
+		constexpr Error field(
+				StringViewCR name,
+				T const*val,
+				std::size_t valLen,
+				SubscriptStack const&subscriptStack) noexcept;
+
+		template<typename T>
+		constexpr Error field(StringViewCR name, T const*val, std::size_t valLen) noexcept;
+
+		template<typename T, bool force>
+		constexpr Error field(StringViewCR name, UnionView<T, force> val) noexcept;
+
+		template<typename T>
+		constexpr Error field(StringViewCR name, const T *val) noexcept;
+
+		template<typename ...Args>
+		constexpr Error fieldCString(StringViewCR name, Args&&...) noexcept;
+
+		[[nodiscard]]
+		constexpr DescriptorType *definition() noexcept {
+			return m_type;
+		}
+
+		static constexpr auto opType() noexcept {
+			return OpType::Reflect;
+		}
+
+	private:
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const int8_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const int16_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const int32_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const int64_t *val) const noexcept;
+
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const uint8_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const uint16_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const uint32_t *val) const noexcept;
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const uint64_t *val) const noexcept;
+
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const bool *val) const noexcept;
+
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const char *val) const noexcept;
+
+		template<std::size_t SmallStrSz>
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const BasicString<SmallStrSz>*) const noexcept {
+			constexpr auto PT = PrimitiveType::String;
+			return getType(types::BasicString, 1, PT, 0, {sfmt("{}", SmallStrSz)});
+		}
+
+		template<std::size_t sz>
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const IString<sz> *val) const noexcept;
+
+		template<typename T>
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const T *val) const noexcept;
+
+		template<typename T>
+		[[nodiscard]]
+		constexpr const DescriptorType *type(const HashMap<String, T> *val) const noexcept;
+
+		template<typename U>
+		[[nodiscard]]
+		constexpr const DescriptorType *type(UnionView<U> val) const noexcept;
+
+		[[nodiscard]]
+		constexpr const DescriptorType *getType(StringViewCR tn, int typeVersion, PrimitiveType t, int b,
+		                                        const TypeParamPack &typeParams = {}) const noexcept;
+
+};
+
+constexpr TypeDescWriter::TypeDescWriter(TypeStore *typeStore) noexcept: m_typeStore(typeStore) {}
+
+template<typename T>
+constexpr ox::Error TypeDescWriter::setTypeInfo(
+		StringViewCR typeName, int typeVersion,
+		const TypeParamPack &typeParams, std::size_t) noexcept {
+	PrimitiveType pt;
+	if constexpr(is_union_v<T>) {
+		pt = PrimitiveType::Union;
+	} else if constexpr(isBasicString_v<T> || isIString_v<T>) {
+		pt = PrimitiveType::String;
+	} else {
+		pt = PrimitiveType::Struct;
+	}
+	m_type = m_typeStore->getInit(typeName, typeVersion, pt, typeParams);
+	m_type->preloadable = preloadable<T>::value;
+	return {};
+}
+
+// array handler
+template<typename T>
+constexpr Error TypeDescWriter::field(StringViewCR name, T const*, std::size_t, SubscriptStack const&subscriptStack) noexcept {
+	if (m_type) {
+		constexpr typename remove_pointer<T>::type *p = nullptr;
+		const auto t = type(p);
+		oxAssert(t != nullptr, "field(const char *name, T *val, std::size_t): Type not found or generated");
+		m_type->fieldList.emplace_back(t, String(name), detail::indirectionLevels_v<T> + 1, subscriptStack, buildTypeId(*t));
+		return {};
+	}
+	return ox::Error(1);
+}
+
+// array handler
+template<typename T>
+constexpr Error TypeDescWriter::field(StringViewCR name, T const*, std::size_t) noexcept {
+	if (m_type) {
+		constexpr typename remove_pointer<T>::type *p = nullptr;
+		const auto t = type(p);
+		oxAssert(t != nullptr, "field(const char *name, T *val, std::size_t): Type not found or generated");
+		auto const lvls = detail::indirectionLevels_v<T> + 1;
+		SubscriptStack subscriptStack{lvls};
+		m_type->fieldList.emplace_back(t, String(name), lvls, subscriptStack, buildTypeId(*t));
+		return {};
+	}
+	return ox::Error(1);
+}
+
+template<typename T, bool force>
+constexpr Error TypeDescWriter::field(StringViewCR name, UnionView<T, force> val) noexcept {
+	if (m_type) {
+		const auto t = type(val);
+		oxAssert(t != nullptr, "field(const char *name, T val): Type not found or generated");
+		m_type->fieldList.emplace_back(t, String(name), 0, SubscriptStack{}, ox::String(t->typeName));
+		return {};
+	}
+	return ox::Error(1);
+}
+
+template<typename T>
+constexpr Error TypeDescWriter::field(StringViewCR name, const T *val) noexcept {
+	if (m_type) {
+		if constexpr(isVector_v<T> || isArray_v<T>) {
+			typename T::value_type *data = nullptr;
+			return field(name, data, 0, detail::buildSubscriptStack(val));
+		} else if constexpr(isSmartPtr_v<T>) {
+			typename T::value_type *data = nullptr;
+			return field(name, data, 0, detail::buildSubscriptStack(val));
+		} else if constexpr(is_pointer_v<T>) {
+			return field(name, val, 0, detail::buildSubscriptStack(val));
+		} else {
+			const auto t = type(val);
+			oxAssert(t != nullptr, "field(const char *name, T *val): Type not found or generated");
+			m_type->fieldList.emplace_back(t, String(name), 0, SubscriptStack{}, buildTypeId(*t));
+			return {};
+		}
+	}
+	return ox::Error(1);
+}
+
+template<typename ...Args>
+constexpr Error TypeDescWriter::fieldCString(StringViewCR name, Args&&...) noexcept {
+	constexpr auto s = "";
+	const auto t = type(s);
+	m_type->fieldList.emplace_back(t, String(name), 0, SubscriptStack{}, ox::String(t->typeName));
+	return {};
+}
+
+template<typename T>
+constexpr const DescriptorType *TypeDescWriter::type(const T *val) const noexcept {
+	if constexpr(isVector_v<T>) {
+		return type(static_cast<typename T::value_type*>(nullptr));
+	} else {
+		auto [t, err] = m_typeStore->template get<T>();
+		if (!err) {
+			return t;
+		} else {
+			TypeDescWriter dw(m_typeStore);
+			const auto reflectErr = model(&dw, val);
+			oxLogError(reflectErr);
+			oxAssert(reflectErr, "field(const char *name, T val): Type info could not be generated");
+			return dw.m_type;
+		}
+	}
+}
+
+template<typename T>
+constexpr const DescriptorType *TypeDescWriter::type(const HashMap<String, T>*) const noexcept {
+	return type(static_cast<T*>(nullptr));
+}
+
+template<typename U>
+constexpr const DescriptorType *TypeDescWriter::type(UnionView<U> val) const noexcept {
+	const auto t = type(val.get());
+	oxAssert(t != nullptr, "field(const char *name, T val): Type not found or generated");
+	return t;
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const int8_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::SignedInteger;
+	constexpr auto Bytes = 1;
+	return getType(types::Int8, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const int16_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::SignedInteger;
+	constexpr auto Bytes = 2;
+	return getType(types::Int16, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const int32_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::SignedInteger;
+	constexpr auto Bytes = 4;
+	return getType(types::Int32, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const int64_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::SignedInteger;
+	constexpr auto Bytes = 8;
+	return getType(types::Int64, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const uint8_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::UnsignedInteger;
+	constexpr auto Bytes = 1;
+	return getType(types::Uint8, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const uint16_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::UnsignedInteger;
+	constexpr auto Bytes = 2;
+	return getType(types::Uint16, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const uint32_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::UnsignedInteger;
+	constexpr auto Bytes = 4;
+	return getType(types::Uint32, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const uint64_t*) const noexcept {
+	constexpr auto PT = PrimitiveType::UnsignedInteger;
+	constexpr auto Bytes = 8;
+	return getType(types::Uint64, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const bool*) const noexcept {
+	constexpr auto PT = PrimitiveType::Bool;
+	constexpr auto Bytes = 0;
+	return getType(types::Bool, 0, PT, Bytes);
+}
+
+constexpr const DescriptorType *TypeDescWriter::type(const char*) const noexcept {
+	constexpr auto PT = PrimitiveType::String;
+	return getType(types::String, 0, PT, 0);
+}
+
+template<std::size_t sz>
+constexpr const DescriptorType *TypeDescWriter::type(const IString<sz>*) const noexcept {
+	constexpr auto PT = PrimitiveType::String;
+	return getType(types::IString, 0, PT, 0);
+}
+
+constexpr const DescriptorType *TypeDescWriter::getType(StringViewCR tn, int typeVersion, PrimitiveType pt, int b,
+                                                        const TypeParamPack &typeParams) const noexcept {
+	auto t = m_typeStore->get(tn, typeVersion, typeParams);
+	if (!t.error) {
+		auto type = t.value;
+		oxAssert(type != nullptr, "TypeDescWriter::getType returning null DescriptorType");
+		return type;
+	} else {
+		auto dt = ox::make_unique<DescriptorType>(String(tn), typeVersion, pt, typeParams);
+		dt->length = b;
+		const auto out = dt.get();
+		const auto typeId = buildTypeId(tn, typeVersion, typeParams);
+		m_typeStore->set(typeId, std::move(dt));
+		return out;
+	}
+}
+
+template<typename T>
+constexpr Result<DescriptorType*> buildTypeDef(TypeStore &typeStore) noexcept {
+	TypeDescWriter writer(&typeStore);
+	ModelHandlerInterface<TypeDescWriter, ox::OpType::Reflect> handler(writer);
+	if (std::is_constant_evaluated()) {
+		std::allocator<T> a;
+		T *t = a.allocate(1);
+		OX_RETURN_ERROR(model(&handler, t));
+		a.deallocate(t, 1);
+	} else {
+		auto t = ox_malloca(sizeof(T), T);
+		OX_RETURN_ERROR(model(&handler, t.get()));
+	}
+	return writer.definition();
+}
+
+template<typename T>
+constexpr Result<DescriptorType*> buildTypeDef(TypeStore &typeStore, T &val) noexcept {
+	TypeDescWriter writer(&typeStore);
+	ModelHandlerInterface<TypeDescWriter, ox::OpType::Reflect> handler(writer);
+	OX_RETURN_ERROR(model(&handler, &val));
+	return writer.definition();
+}
+
+}

src/model/include/ox/model/fieldcounter.hpp

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/assert.hpp>
+#include <ox/std/bit.hpp>
+#include <ox/std/error.hpp>
+
+#include "optype.hpp"
+
+namespace ox {
+
+namespace detail {
+
+template<typename T>
+class FieldCounter {
+	public:
+		std::size_t fields = 0;
+
+		template<typename U = std::nullptr_t>
+		constexpr ox::Error setTypeInfo(StringViewCR = "", int = 0, const Vector<String>& = {}, std::size_t = 0) {
+			return {};
+		}
+
+		template<typename U>
+		constexpr ox::Error field(StringViewCR, U) noexcept {
+			++fields;
+			return {};
+		}
+
+		template<typename U>
+		constexpr ox::Error field(StringViewCR, U, std::size_t) noexcept {
+			++fields;
+			return {};
+		}
+
+		template<typename U, typename Handler>
+		constexpr Error field(StringViewCR, Handler) {
+			++fields;
+			return {};
+		}
+
+		template<typename ...Args>
+		constexpr Error fieldCString(Args&&...) noexcept {
+			++fields;
+			return {};
+		}
+
+		static constexpr auto opType() noexcept {
+			return OpType::Reflect;
+		}
+};
+
+}
+
+namespace detail {
+template<typename T>
+[[nodiscard]]
+consteval auto modelFieldCount() noexcept {
+	auto a = std::allocator<T>();
+	auto t = a.allocate(1);
+	detail::FieldCounter<T> c;
+	const auto err = model(&c, t);
+	oxAssert(err, "Count failed");
+	a.deallocate(t, 1);
+	return c.fields;
+}
+}
+
+template<typename T>
+constexpr auto ModelFieldCount_v = detail::modelFieldCount<T>();
+
+}

src/model/include/ox/model/metadata.hpp

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/byteswap.hpp>
+#include <ox/std/istring.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/trace.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/vector.hpp>
+
+#include "desctypes.hpp"
+#include "fieldcounter.hpp"
+#include "optype.hpp"
+#include "types.hpp"
+
+namespace ox {
+
+namespace detail {
+
+template<bool>
+struct BoolWrapper {
+};
+
+template<int>
+struct IntWrapper {
+};
+
+}
+
+template<typename T, typename = detail::BoolWrapper<true>>
+struct preloadable: false_type {
+};
+
+template<typename T>
+struct preloadable<T, detail::BoolWrapper<T::Preloadable>> {
+	static constexpr bool value = T::Preloadable;
+};
+
+// cannot be done until C++20
+//struct PseudoString {
+//	constexpr PseudoString(const char* = "") noexcept {}
+//};
+//
+//template<PseudoString>
+//struct StringWrapper {
+//};
+//
+//template<typename T, typename = StringWrapper<"">>
+//struct ModelTypeName {
+//	static constexpr const char *value = "";
+//};
+//
+//template<typename T>
+//struct ModelTypeName<T, detail::StringWrapper<T::TypeName>> {
+//	static constexpr const char *value = T::TypeName;
+//};
+
+}

src/model/include/ox/model/model.hpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "def.hpp"
+#include "descread.hpp"
+#include "desctypes.hpp"
+#include "descwrite.hpp"
+#include "fieldcounter.hpp"
+#include "modelhandleradaptor.hpp"
+#include "modelops.hpp"
+#include "modelvalue.hpp"
+#include "typenamecatcher.hpp"
+#include "types.hpp"
+#include "typestore.hpp"
+#include "walk.hpp"

src/model/include/ox/model/modelhandleradaptor.hpp

@@ -0,0 +1,243 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/utility.hpp>
+
+#include "modelvalue.hpp"
+
+namespace ox {
+
+template<typename Handler, OpType opType_v = Handler::opType()>
+class ModelHandlerInterface {
+	private:
+		Handler &m_handler;
+
+	public:
+		constexpr explicit ModelHandlerInterface(Handler &handler) noexcept: m_handler(handler) {
+		}
+
+		template<typename T = std::nullptr_t>
+		constexpr ox::Error setTypeInfo(
+			CString name = T::TypeName,
+			int version = T::TypeVersion,
+			Vector<String> const &typeParams = {}) noexcept {
+			return m_handler.template setTypeInfo<T>(name, version, typeParams, ModelFieldCount_v<T>);
+		}
+
+		template<typename T = std::nullptr_t>
+		constexpr ox::Error setTypeInfo(
+			CString name,
+			int version,
+			Vector<String> const &typeParams,
+			size_t fields) noexcept {
+			return m_handler.template setTypeInfo<T>(name, version, typeParams, fields);
+		}
+
+		template<size_t len>
+		constexpr Error fieldCString(CString name, char val[len]) noexcept {
+			return m_handler.fieldCString(name, &val[0], len);
+		}
+
+		template<size_t len>
+		constexpr Error fieldCString(CString name, char const val[len]) noexcept requires(opType_v != OpType::Read) {
+			if constexpr(opType_v != OpType::Read) {
+				return m_handler.fieldCString(name, &val[0], len);
+			} else {
+				return {};
+			}
+		}
+
+		constexpr Error fieldCString(CString name, char **val) noexcept {
+			return m_handler.fieldCString(name, val);
+		}
+
+		constexpr Error fieldCString(CString name, char const *const*val) noexcept requires(opType_v != OpType::Read) {
+			// this check looks pointless, but it's to address a Clang bug
+			if constexpr(opType_v != OpType::Read) {
+				return m_handler.fieldCString(name, val);
+			} else {
+				return {};
+			}
+		}
+
+		constexpr Error fieldCString(CString name, char const **val) noexcept requires(opType_v != OpType::Read) {
+			// this check looks pointless, but it's to address a Clang bug
+			if constexpr(opType_v != OpType::Read) {
+				return m_handler.fieldCString(name, val);
+			} else {
+				return {};
+			}
+		}
+
+		constexpr Error fieldCString(CString name, char **val, size_t buffLen) noexcept {
+			return m_handler.fieldCString(name, val, buffLen);
+		}
+
+		constexpr Error fieldCString(CString name, char const **val, size_t buffLen) noexcept requires(opType_v != OpType::Read) {
+			// this check looks pointless, but it's to address a Clang bug
+			if constexpr(opType_v != OpType::Read) {
+				return m_handler.fieldCString(name, val, buffLen);
+			} else {
+				return {};
+			}
+		}
+
+		constexpr Error fieldCString(CString name, char *val, size_t buffLen) noexcept {
+			return m_handler.fieldCString(name, val, buffLen);
+		}
+
+		constexpr Error fieldModelValue(char const *name, CommonPtrWith<ModelValue> auto *v) noexcept {
+			switch (v->type()) {
+				case ModelValue::Type::Undefined:
+					break;
+				case ModelValue::Type::Bool:
+					return m_handler.field(name, &v->template get<bool>());
+				case ModelValue::Type::UnsignedInteger8:
+					return m_handler.field(name, &v->template get<uint8_t>());
+				case ModelValue::Type::UnsignedInteger16:
+					return m_handler.field(name, &v->template get<uint16_t>());
+				case ModelValue::Type::UnsignedInteger32:
+					return m_handler.field(name, &v->template get<uint32_t>());
+				case ModelValue::Type::UnsignedInteger64:
+					return m_handler.field(name, &v->template get<uint64_t>());
+				case ModelValue::Type::SignedInteger8:
+					return m_handler.field(name, &v->template get<int8_t>());
+				case ModelValue::Type::SignedInteger16:
+					return m_handler.field(name, &v->template get<int16_t>());
+				case ModelValue::Type::SignedInteger32:
+					return m_handler.field(name, &v->template get<int32_t>());
+				case ModelValue::Type::SignedInteger64:
+					return m_handler.field(name, &v->template get<int64_t>());
+				case ModelValue::Type::String:
+					return m_handler.field(name, &v->template get<String>());
+				case ModelValue::Type::Object:
+					return m_handler.field(name, &v->template get<ModelObject>());
+				case ModelValue::Type::Union:
+				{
+					auto &u = v->template get<ModelUnion>();
+					if constexpr(opType_v == OpType::Read) {
+						u.setActiveField(whichFieldPresent(m_handler, name, u));
+						return m_handler.field(name, UnionView<ModelUnion, true>(&u, u.unionIdx()));
+					} else {
+						return m_handler.field(name, UnionView<ModelUnion const, true>(&u, u.unionIdx()));
+					}
+				}
+				case ModelValue::Type::Vector:
+					return m_handler.field(name, &v->template get<ModelValueVector>());
+				case ModelValue::Type::InlineArray:
+					return m_handler.field(name, &v->template get<ModelValueArray>());
+			}
+			oxErrf("invalid type: {}: {}\n", name, static_cast<int>(v->type()));
+			ox::panic("invalid type");
+			return ox::Error(1, "invalid type");
+		}
+
+		// array handler, with callback to allow handling individual elements
+		template<typename T, typename Callback>
+		constexpr Error field(CString name, Callback cb) noexcept {
+			return m_handler.template field<T, Callback>(name, cb);
+		}
+
+		template<typename T>
+		constexpr Error field(CString name, const T *v) noexcept {
+			if constexpr(ox::is_same_v<T, ModelValue>) {
+				return fieldModelValue(name, v);
+			} else {
+				return m_handler.field(name, v);
+			}
+		}
+
+		template<typename T>
+		constexpr Error field(CString name, T *v) noexcept {
+			if constexpr(ox::is_same_v<T, ModelValue>) {
+				return fieldModelValue(name, v);
+			} else {
+				return m_handler.field(name, v);
+			}
+		}
+
+		template<typename U, bool force = false>
+		constexpr Error field(CString name, UnionView<U, force> val) noexcept {
+			return m_handler.field(name, val);
+		}
+
+		constexpr Error field(CString name, auto *val, size_t len) noexcept {
+			return m_handler.field(name, val, len);
+		}
+
+		/**
+		 * Reads an array length from the current location in the buffer.
+		 * @param name
+		 * @param pass indicates that the parsing should iterate past the array length
+		 */
+		 [[nodiscard]]
+		constexpr auto arrayLength(CString name, bool pass = true) noexcept {
+			return m_handler.arrayLength(name, pass);
+		}
+
+		/**
+		 * Reads an string length from the current location in the buffer.
+		 */
+		[[nodiscard]]
+		constexpr auto stringLength(CString name) noexcept {
+			return m_handler.stringLength(name);
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return Handler::opType();
+		}
+
+		[[nodiscard]]
+		constexpr auto handler() noexcept {
+			return m_handler;
+		}
+
+	private:
+		template<typename H>
+		static constexpr int whichFieldPresent(H &h, CString name, ModelUnion const &u) noexcept
+			requires(H::opType() == OpType::Read) {
+			return h.whichFieldPresent(name, u);
+		}
+
+		template<typename H>
+		static constexpr int whichFieldPresent(H&, CString, ModelUnion const&) noexcept
+			requires(H::opType() != OpType::Read) {
+			return 0;
+		}
+
+};
+
+template<typename Handler, OpType opType_v = Handler::opType()>
+class ModelHandlerBase {
+	private:
+		ModelHandlerInterface<Handler, opType_v> m_interface{*static_cast<Handler*>(this)};
+	public:
+		[[nodiscard]]
+		constexpr auto interface() noexcept {
+			return &m_interface;
+		}
+		[[nodiscard]]
+		static constexpr OpType opType() noexcept {
+			return opType_v;
+		}
+};
+
+
+constexpr ox::Error resizeVector(auto &vec, size_t sz) {
+	if constexpr(ox::is_same_v<decltype(vec.resize(0)), ox::Error>) {
+		return vec.resize(sz);
+	} else {
+		vec.resize(sz);
+		return {};
+	}
+}
+
+}

src/model/include/ox/model/modelops.hpp

@@ -0,0 +1,303 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/bit.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/utility.hpp>
+
+#include "fieldcounter.hpp"
+#include "modelvalue.hpp"
+#include "optype.hpp"
+#include "types.hpp"
+
+namespace ox {
+
+namespace detail {
+
+class Wrap {
+	public:
+		virtual ~Wrap() = default;
+};
+
+template<typename T>
+class WrapT: public Wrap {
+	private:
+		T *m_obj = nullptr;
+
+	public:
+		constexpr WrapT(T *obj) noexcept: m_obj(obj) {
+		}
+		constexpr WrapT() = default;
+
+		[[nodiscard]]
+		constexpr auto obj() noexcept {
+			return m_obj;
+		}
+
+};
+
+template<std::size_t size>
+class MemberList {
+
+	private:
+		std::size_t m_i = 0;
+
+	public:
+		Array<void*, size> vars;
+
+		template<typename T>
+		constexpr Error field(const char*, T *v) noexcept {
+			vars[m_i++] = static_cast<void*>(v);
+			return {};
+		}
+
+		template<typename T>
+		constexpr Error field(const char*, T *v, int) noexcept {
+			vars[m_i++] = static_cast<void*>(v);
+			return {};
+		}
+
+		template<typename U, bool force = false>
+		constexpr Error field(const char*, UnionView<U, force> u) noexcept {
+			vars[m_i++] = static_cast<void*>(u.get());
+			return {};
+		}
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion,
+				const Vector<String>& = {},
+				std::size_t = ModelFieldCount_v<T>) noexcept {
+			return {};
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Reflect;
+		}
+
+};
+
+template<std::size_t size>
+class Copier {
+
+	private:
+		std::size_t m_i = 0;
+		MemberList<size> *m_dst = nullptr;
+
+	public:
+		constexpr explicit Copier(MemberList<size> *dst) noexcept: m_dst(dst) {
+		}
+
+		template<typename FT>
+		constexpr Error field(const char *name, const FT *v) noexcept {
+			if constexpr(isVector_v<FT>) {
+				return field(name, v->data(), v->size());
+			} else {
+				auto &src = *v;
+				auto &dst = *cbit_cast<FT*>(m_dst->vars[m_i]);
+				dst = src;
+				++m_i;
+				return {};
+			}
+		}
+
+		template<typename FT>
+		constexpr Error field(const char*, const FT *list, int elements) {
+			for (auto i = 0l; i < elements; ++i) {
+				auto &src = list[i];
+				auto &dst = cbit_cast<FT*>(m_dst->vars[m_i])[i];
+				dst = src;
+			}
+			++m_i;
+			return {};
+		}
+
+		template<typename U, bool force = false>
+		constexpr Error field(const char*, UnionView<U, force> u) {
+			auto &dst = *cbit_cast<U*>(m_dst->vars[m_i]);
+			auto &src = *u.get();
+			dst = src;
+			++m_i;
+			return {};
+		}
+
+		template<typename T = void>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion,
+				const Vector<String>& = {},
+				int = ModelFieldCount_v<T>) noexcept {
+			return {};
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Read;
+		}
+
+};
+
+template<std::size_t size>
+class Mover {
+
+	private:
+		std::size_t m_i = 0;
+		MemberList<size> *m_dst = nullptr;
+
+	public:
+		constexpr explicit Mover(MemberList<size> *dst) noexcept: m_dst(dst) {
+		}
+
+		template<typename FT>
+		constexpr Error field(const char *name, FT *v) noexcept {
+			if constexpr(isVector_v<FT>) {
+				return field(name, v->data(), v->size());
+			} else {
+				auto &src = *v;
+				auto &dst = *cbit_cast<FT*>(m_dst->vars[m_i]);
+				dst = std::move(src);
+				src = FT{};
+				++m_i;
+				return {};
+			}
+		}
+
+		template<typename FT>
+		constexpr Error field(const char*, FT *list, int elements) noexcept {
+			for (auto i = 0l; i < elements; ++i) {
+				auto &src = list[i];
+				auto &dst = cbit_cast<FT*>(m_dst->vars[m_i])[i];
+				dst = std::move(src);
+				src = FT{};
+			}
+			++m_i;
+			return {};
+		}
+
+		template<typename U, bool force = false>
+		constexpr Error field(const char*, UnionView<U, force> u) noexcept {
+			auto &dst = *cbit_cast<U*>(m_dst->vars[m_i]);
+			auto &src = *u.get();
+			dst = std::move(src);
+			++m_i;
+			return {};
+		}
+
+		template<typename T = void>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion,
+				const Vector<String>& = {},
+				int = ModelFieldCount_v<T>) noexcept {
+			return {};
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Read;
+		}
+
+};
+
+template<std::size_t size>
+class Equals {
+
+	private:
+		std::size_t m_i = 0;
+		MemberList<size> *m_other = nullptr;
+
+	public:
+		bool value = false;
+
+		constexpr Equals(MemberList<size> *other) noexcept: m_other(other) {
+		}
+
+		template<typename FT>
+		constexpr Error field(const char*, const FT *v) noexcept {
+			const auto &src = *v;
+			const auto &dst = std::bit_cast<FT>(*m_other->vars[m_i]);
+			++m_i;
+			if (dst == src) {
+				return {};
+			} else {
+				this->value = false;
+				return ox::Error(1);
+			}
+		}
+
+		template<typename FT>
+		constexpr Error field(const char*, const FT *list, int elements) noexcept {
+			for (auto i = 0l; i < elements; ++i) {
+				const auto &src = list[i];
+				const auto &dst = cbit_cast<FT*>(m_other->vars[m_i])[i];
+				if (!(dst == src)) {
+					this->value = false;
+					return ox::Error(1);
+				}
+			}
+			++m_i;
+			return {};
+		}
+
+		template<typename U, bool force = false>
+		constexpr Error field(const char*, UnionView<U, force> u) noexcept {
+			const auto &dst = *cbit_cast<U*>(m_other->vars[m_i]);
+			const auto &src = *u.get();
+			++m_i;
+			if (dst == src) {
+				return {};
+			} else {
+				this->value = false;
+				return ox::Error(1);
+			}
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Read;
+		}
+
+};
+
+}
+
+template<typename T>
+constexpr void moveModel(T *dst, T *src) noexcept {
+	constexpr auto size = ModelFieldCount_v<T>;
+	detail::MemberList<size> dstFields;
+	detail::Mover<size> mover(&dstFields);
+	std::ignore = model(&dstFields, dst);
+	std::ignore = model(&mover, src);
+}
+
+template<typename T>
+constexpr void copyModel(T *dst, const T *src) noexcept {
+	constexpr auto size = ModelFieldCount_v<T>;
+	detail::MemberList<size> dstFields;
+	detail::Copier<size> copier(&dstFields);
+	std::ignore = model(&dstFields, dst);
+	std::ignore = model(&copier, src);
+}
+
+template<typename T>
+[[nodiscard]]
+constexpr bool equalsModel(T *a, T *b) noexcept {
+	constexpr auto size = T::Fields;
+	detail::MemberList<size> aFields;
+	detail::Equals<size> equals(&aFields);
+	std::ignore = model(&aFields, a);
+	std::ignore = model(&equals, b);
+	return equals.value;
+}
+
+}

src/model/include/ox/model/optype.hpp

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/stringview.hpp>
+
+namespace ox {
+
+enum class OpType {
+	Read = 1,
+	Write,
+	Reflect,
+};
+
+}

src/model/include/ox/model/typenamecatcher.hpp

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+
+#include "fieldcounter.hpp"
+#include "optype.hpp"
+
+namespace ox {
+
+struct TypeInfoCatcher {
+
+	CString name = "";
+	int version = 0;
+
+	template<typename T = std::nullptr_t>
+	constexpr Error setTypeInfo(
+			CString const n = T::TypeName,
+			int const v = T::TypeVersion,
+			Vector<String> const& = {},
+			size_t = 0) noexcept {
+		this->name = n;
+		this->version = v;
+		return {};
+	}
+
+	template<typename T>
+	constexpr Error field(CString, T*, size_t) noexcept {
+		return {};
+	}
+
+	template<typename T>
+	constexpr Error field(CString, T const&) noexcept {
+		return {};
+	}
+
+	template<typename T>
+	constexpr Error fieldCString(CString, T const&) noexcept {
+		return {};
+	}
+
+	static constexpr auto opType() noexcept {
+		return OpType::Reflect;
+	}
+
+};
+
+template<typename T>
+[[nodiscard]]
+constexpr int getModelTypeVersion(T *val) noexcept {
+	TypeInfoCatcher nc;
+	std::ignore = model(&nc, val);
+	return nc.version;
+}
+
+template<typename T>
+[[nodiscard]]
+constexpr int getModelTypeVersion() noexcept {
+	std::allocator<T> a;
+	const auto t = a.allocate(1);
+	const auto out = getModelTypeVersion(t);
+	a.deallocate(t, 1);
+	return out;
+}
+
+template<typename T>
+[[nodiscard]]
+consteval int requireModelTypeVersion() noexcept {
+	constexpr auto version = getModelTypeVersion<T>();
+	static_assert(version != 0, "TypeVersion is required");
+	return version;
+}
+
+template<typename T, typename Str = const char*>
+[[nodiscard]]
+constexpr Str getModelTypeName(T *val) noexcept {
+	TypeInfoCatcher nc;
+	std::ignore = model(&nc, val);
+	return nc.name;
+}
+
+template<typename T, typename Str = const char*>
+[[nodiscard]]
+consteval Str getModelTypeName() noexcept {
+	std::allocator<T> a;
+	auto t = a.allocate(1);
+	auto out = getModelTypeName(t);
+	a.deallocate(t, 1);
+	return out;
+}
+
+template<typename T, typename Str = StringLiteral>
+[[nodiscard]]
+consteval auto requireModelTypeName() noexcept {
+	constexpr auto name = getModelTypeName<T, Str>();
+	static_assert(StringView{name}.size(), "Type lacks required TypeName");
+	return name;
+}
+
+template<typename T, typename Str = StringLiteral>
+constexpr auto ModelTypeName_v = requireModelTypeName<T, Str>();
+
+template<typename T, typename Str = const char*>
+constexpr auto ModelTypeVersion_v = requireModelTypeVersion<T>();
+
+template<typename T>
+constexpr auto ModelTypeId_v = [] {
+	constexpr auto name = ModelTypeName_v<T, StringView>;
+	constexpr auto version = ModelTypeVersion_v<T>;
+	constexpr auto versionStr = ox::sfmt<IString<19>>("{}", version);
+	return ox::sfmt<IString<name.size() + versionStr.size() + 1>>("{};{}", name, versionStr);
+}();
+
+}

src/model/include/ox/model/types.hpp

@@ -0,0 +1,200 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#if __has_include(<vector>)
+#include <vector>
+#endif
+
+#if __has_include(<array>)
+#include <array>
+#endif
+
+#if __has_include(<QVector>)
+#include <QVector>
+#endif
+
+#include <ox/std/array.hpp>
+#include <ox/std/istring.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/strops.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/typetraits.hpp>
+#include <ox/std/vector.hpp>
+
+namespace ox {
+
+namespace types {
+constexpr StringLiteral BasicString = "net.drinkingtea.ox.BasicString";
+constexpr StringLiteral IString     = "net.drinkingtea.ox.IString";
+constexpr StringLiteral String      = "B.string";
+constexpr StringLiteral Bool        = "B.bool";
+constexpr StringLiteral Uint8       = "B.uint8";
+constexpr StringLiteral Uint16      = "B.uint16";
+constexpr StringLiteral Uint32      = "B.uint32";
+constexpr StringLiteral Uint64      = "B.uint64";
+constexpr StringLiteral Int8        = "B.int8";
+constexpr StringLiteral Int16       = "B.int16";
+constexpr StringLiteral Int32       = "B.int32";
+constexpr StringLiteral Int64       = "B.int64";
+}
+
+template<typename T>
+consteval bool isBasicString(const T*) noexcept {
+	return false;
+}
+
+template<std::size_t SmallVecSize>
+consteval bool isBasicString(const BasicString<SmallVecSize>*) noexcept {
+	return true;
+}
+
+template<typename T>
+constexpr bool isBasicString_v = isBasicString(static_cast<const T*>(nullptr));
+
+static_assert(isBasicString_v<ox::BasicString<0ul>>);
+static_assert(isBasicString_v<ox::BasicString<8ul>>);
+static_assert(isBasicString_v<ox::String>);
+
+template<typename T>
+consteval bool isIString(const T*) noexcept {
+	return false;
+}
+
+template<std::size_t SmallVecSize>
+consteval bool isIString(const BasicString<SmallVecSize>*) noexcept {
+	return true;
+}
+
+template<typename T>
+constexpr bool isIString_v = isIString(static_cast<const T*>(nullptr));
+
+static_assert(isBasicString_v<ox::BasicString<0ul>>);
+static_assert(isBasicString_v<ox::BasicString<8ul>>);
+static_assert(isBasicString_v<ox::String>);
+
+template<typename T>
+consteval bool isOxVector(const T*) noexcept {
+	return false;
+}
+
+template<typename T, std::size_t SmallVecSize>
+consteval bool isOxVector(const Vector<T, SmallVecSize>*) noexcept {
+	return true;
+}
+
+template<typename T>
+constexpr bool isOxVector_v = isVector(static_cast<const T*>(nullptr));
+
+template<typename T>
+consteval bool isVector(const T*) noexcept {
+	return false;
+}
+
+template<typename T, std::size_t SmallVecSize>
+consteval bool isVector(const Vector<T, SmallVecSize>*) noexcept {
+	return true;
+}
+
+#if __has_include(<vector>)
+template<typename T>
+consteval bool isVector(const std::vector<T>*) noexcept {
+	return true;
+}
+#endif
+
+#if __has_include(<QVector>)
+template<typename T>
+constexpr bool isVector(const QVector<T>*) noexcept {
+	return true;
+}
+#endif
+
+template<typename T>
+constexpr bool isVector_v = isVector(static_cast<const T*>(nullptr));
+
+static_assert(isVector_v<ox::Vector<unsigned int, 0ul>>);
+
+template<typename T>
+constexpr bool isBareArray_v = false;
+
+template<typename T>
+constexpr bool isBareArray_v<T[]> = true;
+
+template<typename T, std::size_t sz>
+constexpr bool isBareArray_v<T[sz]> = true;
+
+template<typename T>
+consteval bool isArray(T*) noexcept {
+	return false;
+}
+
+template<typename T>
+constexpr bool isArray_v = isArray(static_cast<T*>(nullptr));
+
+template<typename T>
+constexpr bool isArray_v<T[]> = true;
+
+template<typename T, std::size_t sz>
+constexpr bool isArray_v<T[sz]> = true;
+
+template<typename T, std::size_t sz>
+constexpr bool isArray_v<Array<T, sz>> = true;
+
+template<typename T, std::size_t sz>
+consteval bool isArray(T[sz]) noexcept {
+	return true;
+}
+
+template<typename T, std::size_t sz>
+consteval bool isArray(Array<T, sz>) noexcept {
+	return true;
+}
+
+template<typename T>
+constexpr bool isSmartPtr_v = false;
+
+template<typename T>
+constexpr bool isSmartPtr_v<::ox::UPtr<T>> = true;
+
+#if __has_include(<array>)
+template<typename T>
+constexpr bool isSmartPtr_v<::std::unique_ptr<T>> = true;
+#endif
+
+
+template<typename Union, bool force = false> requires(force || is_union_v<Union>)
+class UnionView {
+
+	protected:
+		int m_idx = -1;
+		Union *m_union = nullptr;
+
+	public:
+		constexpr UnionView(Union *u, int idx) noexcept: m_idx(idx), m_union(u) {
+		}
+
+		[[nodiscard]]
+		constexpr auto idx() const noexcept {
+			return m_idx;
+		}
+
+		[[nodiscard]]
+		constexpr const Union *get() const noexcept {
+			return m_union;
+		}
+
+		[[nodiscard]]
+		constexpr Union *get() noexcept {
+			return m_union;
+		}
+
+};
+
+}

src/model/include/ox/model/typestore.hpp

@@ -0,0 +1,120 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/fmt.hpp>
+#include <ox/std/hashmap.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/typetraits.hpp>
+
+#include "typenamecatcher.hpp"
+#include "desctypes.hpp"
+
+namespace ox {
+
+class TypeStore {
+	private:
+		HashMap<String, UPtr<DescriptorType>> m_cache;
+
+	public:
+		constexpr TypeStore() noexcept = default;
+
+		constexpr virtual ~TypeStore() noexcept = default;
+
+		constexpr Result<const DescriptorType*> get(const auto &name, int typeVersion,
+		                                            const TypeParamPack &typeParams) const noexcept {
+			const auto typeId = buildTypeId(name, typeVersion, typeParams);
+			OX_REQUIRE(out, m_cache.at(typeId));
+			return out->get();
+		}
+
+		template<typename T>
+		constexpr Result<const DescriptorType*> get() const noexcept {
+			constexpr auto typeName = ModelTypeName_v<T>;
+			constexpr auto typeVersion = ModelTypeVersion_v<T>;
+			const auto typeId = buildTypeId(typeName, typeVersion, {});
+			OX_REQUIRE(out, m_cache.at(typeId));
+			return out->get();
+		}
+
+		constexpr DescriptorType *getInit(StringViewCR typeName, int typeVersion, PrimitiveType pt,
+		                                  const TypeParamPack &typeParams) noexcept {
+			const auto typeId = buildTypeId(typeName, typeVersion, typeParams);
+			auto &out = m_cache[typeId];
+			out = ox::make_unique<DescriptorType>(String(typeName), typeVersion, pt, typeParams);
+			return out.get();
+		}
+
+		constexpr Result<const DescriptorType*> getLoad(const auto &typeId) noexcept {
+			auto [val, err] = m_cache.at(typeId);
+			if (err) {
+				if (!std::is_constant_evaluated()) {
+					OX_REQUIRE_M(dt, loadDescriptor(typeId));
+					for (auto &f : dt->fieldList) {
+						if (typeId == f.typeId) {
+							f.type = dt.get();
+						} else {
+							OX_RETURN_ERROR(this->getLoad(f.typeId).moveTo(f.type));
+						}
+					}
+					auto &out = m_cache[typeId];
+					out = std::move(dt);
+					return out.get();
+				} else {
+					return ox::Error(1, "Type not available");
+				}
+			}
+			return val->get();
+		}
+
+		constexpr Result<const DescriptorType*> getLoad(const auto &typeName, auto typeVersion,
+		                                                const TypeParamPack &typeParams = {}) noexcept {
+			return getLoad(buildTypeId(typeName, typeVersion, typeParams));
+		}
+
+		template<typename T>
+		constexpr Result<const DescriptorType*> getLoad() noexcept {
+			constexpr auto typeName = requireModelTypeName<T>();
+			constexpr auto typeVersion = requireModelTypeVersion<T>();
+			return getLoad(typeName, typeVersion);
+		}
+
+		constexpr void set(const auto &typeId, UPtr<DescriptorType> dt) noexcept {
+			m_cache[typeId] = std::move(dt);
+		}
+
+		constexpr void set(const auto &typeId, DescriptorType *dt) noexcept {
+			m_cache[typeId] = UPtr<DescriptorType>(dt);
+		}
+
+		[[nodiscard]]
+		constexpr auto typeList() const noexcept {
+			const auto &keys = m_cache.keys();
+			ox::Vector<DescriptorType*> descs;
+			for (const auto &k : keys) {
+				descs.emplace_back(m_cache.at(k).unwrap()->get());
+			}
+			return descs;
+		}
+
+	protected:
+		virtual Result<UPtr<DescriptorType>> loadDescriptor(ox::StringView) noexcept {
+			return ox::Error(1);
+		}
+
+		Result<UPtr<DescriptorType>> loadDescriptor(ox::StringViewCR name, int version,
+		                                                 const ox::TypeParamPack &typeParams) noexcept {
+			const auto typeId = buildTypeId(name, version, typeParams);
+			return loadDescriptor(typeId);
+		}
+
+};
+
+}

src/model/include/ox/model/walk.hpp

@@ -0,0 +1,161 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/error.hpp>
+
+#include "desctypes.hpp"
+
+namespace ox {
+
+template<typename Reader, typename T>
+class DataWalker {
+	template<typename ReaderBase, typename FH>
+	friend constexpr Error parseField(const DescriptorField &field, ReaderBase *rdr, DataWalker<ReaderBase, FH> *walker) noexcept;
+
+	private:
+		Vector<const DescriptorType*> m_typeStack;
+		T m_fieldHandler;
+		Vector<FieldName> m_path;
+		Vector<String> m_typePath;
+
+	public:
+		constexpr DataWalker(DescriptorType *type, T fieldHandler) noexcept;
+
+		constexpr Result<const DescriptorType*> type() const noexcept;
+
+		constexpr Error read(const DescriptorField&, Reader *rdr) noexcept;
+
+	protected:
+		constexpr void pushNamePath(const FieldName &fn) noexcept;
+
+		constexpr void popNamePath() noexcept;
+
+		constexpr void pushType(const DescriptorType *type) noexcept;
+
+		constexpr void popType() noexcept;
+
+};
+
+template<typename Reader, typename T>
+constexpr DataWalker<Reader, T>::DataWalker(DescriptorType *type, T fieldHandler) noexcept: m_fieldHandler(fieldHandler) {
+	m_typeStack.push_back(type);
+}
+
+template<typename Reader, typename T>
+constexpr Result<const DescriptorType*> DataWalker<Reader, T>::type() const noexcept {
+	OX_REQUIRE(out, m_typeStack.back());
+	return *out;
+}
+
+template<typename Reader, typename T>
+constexpr Error DataWalker<Reader, T>::read(const DescriptorField &f, Reader *rdr) noexcept {
+	// get const ref of paths
+	const auto &pathCr = m_path;
+	const auto &typePathCr = m_typePath;
+	return m_fieldHandler(pathCr, typePathCr, f, rdr);
+}
+
+template<typename Reader, typename T>
+constexpr void DataWalker<Reader, T>::pushNamePath(const FieldName &fn) noexcept {
+	m_path.emplace_back(fn);
+}
+
+template<typename Reader, typename T>
+constexpr void DataWalker<Reader, T>::popNamePath() noexcept {
+	m_path.pop_back();
+}
+
+template<typename Reader, typename T>
+constexpr void DataWalker<Reader, T>::pushType(const DescriptorType *type) noexcept {
+	m_typeStack.push_back(type);
+}
+
+template<typename Reader, typename T>
+constexpr void DataWalker<Reader, T>::popType() noexcept {
+	m_typeStack.pop_back();
+}
+
+template<typename Reader, typename FH>
+static constexpr Error parseField(const DescriptorField &field, Reader *rdr, DataWalker<Reader, FH> *walker) noexcept {
+	walker->pushNamePath(field.fieldName);
+	if (field.subscriptLevels) {
+		// add array handling
+		OX_REQUIRE(arrayLen, rdr->arrayLength(field.fieldName.c_str(), true));
+		auto child = rdr->child(field.fieldName.c_str());
+		OX_RETURN_ERROR(child.setTypeInfo(field.type->typeName.c_str(), field.type->typeVersion, field.type->typeParams, arrayLen));
+		DescriptorField f(field); // create mutable copy
+		--f.subscriptLevels;
+		String subscript;
+		for (std::size_t i = 0; i < arrayLen; i++) {
+			subscript = "[";
+			subscript += static_cast<uint64_t>(i);
+			subscript += "]";
+			walker->pushNamePath(subscript);
+			OX_RETURN_ERROR(parseField(f, &child, walker));
+			walker->popNamePath();
+		}
+		rdr->nextField();
+	} else {
+		switch (field.type->primitiveType) {
+			case PrimitiveType::UnsignedInteger:
+			case PrimitiveType::SignedInteger:
+			case PrimitiveType::Bool:
+			case PrimitiveType::String:
+				OX_RETURN_ERROR(walker->read(field, rdr));
+				break;
+			case PrimitiveType::Struct:
+			case PrimitiveType::Union:
+				if (rdr->fieldPresent(field.fieldName.c_str())) {
+					auto child = rdr->child(field.fieldName.c_str());
+					walker->pushType(field.type);
+					OX_RETURN_ERROR(model(&child, walker));
+					walker->popType();
+					rdr->nextField();
+				} else {
+					// skip and discard absent field
+					int discard;
+					OX_RETURN_ERROR(rdr->field(field.fieldName.c_str(), &discard));
+				}
+				break;
+		}
+	}
+	walker->popNamePath();
+	return {};
+}
+
+template<typename Reader, typename FH>
+constexpr Error model(Reader *rdr, DataWalker<Reader, FH> *walker) noexcept {
+	OX_REQUIRE(type, walker->type());
+	auto typeName = type->typeName.c_str();
+	auto typeVersion = type->typeVersion;
+	auto typeParams = type->typeParams;
+	auto &fields = type->fieldList;
+	OX_RETURN_ERROR(rdr->setTypeInfo(typeName, typeVersion, typeParams, fields.size()));
+	for (const auto &field : fields) {
+		OX_RETURN_ERROR(parseField(field, rdr, walker));
+	}
+	return {};
+}
+
+template<typename Reader, typename Handler>
+constexpr Error walkModel(DescriptorType *type, Reader_c auto &reader, Handler handler) noexcept {
+	DataWalker<Reader, Handler> walker(type, handler);
+	Reader rdr(reader);
+	return model(&rdr, &walker);
+}
+
+template<typename Reader, typename Handler>
+constexpr Error walkModel(DescriptorType *type, const char *data, std::size_t dataLen, Handler handler) noexcept {
+	DataWalker<Reader, Handler> walker(type, handler);
+	Reader rdr(reinterpret_cast<const uint8_t*>(data), dataLen);
+	return model(&rdr, &walker);
+}
+
+}

src/model/src/desctypes.cpp

@@ -0,0 +1,13 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/model/desctypes.hpp>
+
+namespace ox {
+
+}

src/model/src/descwrite.cpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/model/descwrite.hpp>
+
+namespace ox {
+
+namespace detail {
+
+struct preloadable_type {
+	static constexpr auto Preloadable = true;
+};
+
+struct non_preloadable_type {
+	static constexpr auto Preloadable = false;
+};
+
+struct non_preloadable_type2 {
+};
+
+static_assert(preloadable<preloadable_type>::value);
+static_assert(!preloadable<non_preloadable_type>::value);
+static_assert(!preloadable<non_preloadable_type2>::value);
+
+}
+
+
+static_assert([] {
+	return detail::indirectionLevels_v<int> == 0;
+}(), "indirectionLevels broken: indirectionLevels(int)");
+
+static_assert([] {
+	return detail::indirectionLevels_v<int*> == 1;
+}(), "indirectionLevels broken: indirectionLevels(int*)");
+
+static_assert([] {
+	return detail::indirectionLevels_v<int[2]> == 1;
+}(), "indirectionLevels broken: indirectionLevels(int[])");
+
+static_assert([] {
+	return detail::indirectionLevels_v<int**> == 2;
+}(), "indirectionLevels broken: indirectionLevels(int[])");
+
+}

src/model/src/modelvalue.cpp

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/hashmap.hpp>
+
+#include <ox/model/modelvalue.hpp>
+
+namespace ox {
+
+static_assert([]() -> Error {
+	ModelValue v;
+	OX_RETURN_ERROR(v.setType<int32_t>());
+	if (v.type() != ModelValue::Type::SignedInteger32) {
+		return Error(1, "type is wrong");
+	}
+	//oxReturnError(v.set<int32_t>(5));
+	return {};
+}() == Error{});
+
+// a dummy function to prevent linker errors in a library that has no other symbols
+void modelDummyFunc() noexcept {}
+
+}

src/model/test/CMakeLists.txt

@@ -0,0 +1,13 @@
+add_executable(
+	ModelTest
+		tests.cpp
+)
+
+target_link_libraries(
+	ModelTest
+		OxModel
+)
+
+add_test("[ox/model] ModelValue" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ModelTest ModelValue)
+add_test("[ox/model] getModelTypeName" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ModelTest getModelTypeName)
+add_test("[ox/model] getModelTypeVersion" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ModelTest getModelTypeVersion)

src/model/test/tests.cpp

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#undef NDEBUG
+
+#include <map>
+#include <ox/model/model.hpp>
+#include <ox/std/std.hpp>
+
+struct TestType {
+	static constexpr auto TypeName = "net.drinkingtea.model.test.TestType";
+	static constexpr auto TypeVersion = 1;
+};
+
+OX_MODEL_BEGIN(TestType)
+OX_MODEL_END()
+
+struct TestType2 {
+};
+
+template<typename Str = ox::StringView>
+constexpr auto getModelTypeName(TestType2*) noexcept {
+	return "net.drinkingtea.model.test.TestType2";
+}
+
+constexpr auto getModelTypeVersion(TestType2*) noexcept {
+	return 2;
+}
+
+std::map<ox::StringView, ox::Error(*)()> tests = {
+	{
+		{
+			"ModelValue",
+			[] {
+				ox::ModelValue v;
+				OX_RETURN_ERROR(v.setType<int32_t>());
+				//v.m_type = ox::ModelValue::getType<int32_t>();
+				if (v.type() != ox::ModelValue::Type::SignedInteger32) {
+					return ox::Error(1, "type is wrong");
+				}
+				OX_RETURN_ERROR(v.set<int32_t>(5));
+				return ox::Error{};
+			}
+		},
+
+		{
+			"getModelTypeName",
+			[] {
+				oxAssert(ox::getModelTypeName<TestType>() == TestType::TypeName, "getModelTypeName call failed");
+				oxAssert(ox::getModelTypeName<TestType2>() == ox::StringView("net.drinkingtea.model.test.TestType2"), "getModelTypeName call failed");
+				return ox::Error{};
+			}
+		},
+
+		{
+			"getModelTypeVersion",
+			[] {
+				oxAssert(ox::getModelTypeVersion<TestType>() == TestType::TypeVersion, "getModelTypeVersion call failed");
+				oxAssert(ox::getModelTypeVersion<TestType2>() == 2, "getModelTypeVersion call failed");
+				return ox::Error{};
+			}
+		},
+	}
+};
+
+int main(int argc, const char **args) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+	}
+	auto const testName = args[1];
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/oc/CMakeLists.txt

@@ -0,0 +1,50 @@
+add_library(
+	OxOrganicClaw
+		src/read.cpp
+		src/write.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxOrganicClaw PRIVATE -Wsign-conversion)
+	target_compile_options(OxOrganicClaw PRIVATE -Wconversion)
+endif()
+
+target_link_libraries(
+	OxOrganicClaw PUBLIC
+		OxModel
+		jsoncpp_object
+)
+
+target_include_directories(
+	OxOrganicClaw PUBLIC
+		${JSONCPP_INCLUDE_DIR}
+)
+
+set_property(
+	TARGET
+		OxOrganicClaw
+	PROPERTY
+		POSITION_INDEPENDENT_CODE ON
+)
+
+target_include_directories(
+	OxOrganicClaw PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS OxOrganicClaw
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/oc/include/ox/oc/oc.hpp

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "read.hpp"
+#include "write.hpp"

src/oc/include/ox/oc/read.hpp

@@ -0,0 +1,313 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/def.hpp>
+
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+#include <json/json.h>
+OX_ALLOW_UNSAFE_BUFFERS_END
+
+#include <ox/model/fieldcounter.hpp>
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/typenamecatcher.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/hashmap.hpp>
+#include <ox/std/memops.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/uuid.hpp>
+
+namespace ox {
+
+class OrganicClawReader {
+
+	private:
+		Json::Value m_json;
+		Json::ArrayIndex m_fieldIt = 0;
+		int const m_unionIdx = -1;
+
+	public:
+		OrganicClawReader() noexcept = default;
+
+		OrganicClawReader(uint8_t const *buff, size_t buffSize);
+
+		OrganicClawReader(CString json, size_t buffSize);
+
+		explicit OrganicClawReader(Json::Value json, int unionIdx = -1) noexcept;
+
+		Error field(CString key, bool *val) noexcept;
+
+		// array handler
+		template<typename T>
+		Error field(CString key, T *val, size_t len) noexcept;
+
+		template<typename T>
+		Error field(CString, HashMap<String, T> *val) noexcept;
+
+		template<typename T>
+		Error field(CString key, T *val) noexcept;
+
+		template<typename U, bool force = false>
+		Error field(CString key, UnionView<U, force> val) noexcept;
+
+		template<size_t L>
+		Error field(CString key, BasicString<L> *val) noexcept;
+
+		template<size_t L>
+		Error field(CString key, IString<L> *val) noexcept;
+
+		Error fieldCString(CString key, char *val, size_t buffLen) noexcept;
+
+		Error fieldCString(CString key, char **val) noexcept;
+
+		Error fieldCString(CString key, char **val, size_t buffLen) noexcept;
+
+		Error field(CString key, UUID *val) noexcept;
+
+		/**
+		 * Reads an array length from the current location in the buffer.
+		 * @param key
+		 * @param pass indicates that the parsing should iterate past the array length
+		 */
+		Result<size_t> arrayLength(CString key, bool pass = true) noexcept;
+
+		/**
+		 * Reads an string length from the current location in the buffer.
+		 */
+		[[nodiscard]]
+		size_t stringLength(CString key) noexcept;
+
+		template<typename T = void>
+		constexpr Error setTypeInfo() noexcept {
+			return {};
+		}
+
+		template<typename T = void>
+		constexpr Error setTypeInfo(CString) noexcept {
+			return {};
+		}
+
+		template<typename T = void>
+		constexpr Error setTypeInfo(CString, int, const Vector<String>& = {}) noexcept {
+			return {};
+		}
+
+		template<typename T = void>
+		constexpr Error setTypeInfo(CString, int, const Vector<String>& = {}, size_t = {}) noexcept {
+			return {};
+		}
+
+		/**
+		 * Returns a OrganicClawReader to parse a child object.
+		 */
+		[[nodiscard]]
+		OrganicClawReader child(CString key, int unionIdx = -1) noexcept;
+
+		// compatibility stub
+		constexpr void nextField() noexcept {}
+
+		[[nodiscard]]
+		bool fieldPresent(CString key) noexcept;
+
+		[[nodiscard]]
+		int whichFieldPresent(CString name, const ModelUnion &u) const noexcept;
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Read;
+		}
+
+	private:
+		[[nodiscard]]
+		Json::Value &value(CString key) noexcept;
+
+		[[nodiscard]]
+		bool targetValid() const noexcept;
+
+};
+
+template<typename T>
+Error OrganicClawReader::field(CString key, T *val) noexcept {
+	Error err{};
+	try {
+		if constexpr (is_integer_v<T>) {
+			if (targetValid()) {
+				auto const &jv = value(key);
+				auto const rightType = sizeof(T) == 8 ?
+					(is_signed_v<T> ? jv.isInt64() : jv.isUInt64()) :
+					(is_signed_v<T> ? jv.isInt() : jv.isUInt());
+				if (jv.empty()) {
+					*val = 0;
+				} else if (rightType) {
+					if constexpr(is_signed_v<T>) {
+						*val = static_cast<T>(jv.asInt64());
+					} else {
+						*val = static_cast<T>(jv.asUInt64());
+					}
+				} else {
+					err = Error{1, "Type mismatch"};
+				}
+			}
+		} else if constexpr (isVector_v<T>) {
+			auto const &srcVal = value(key);
+			auto const srcSize = srcVal.size();
+			OX_RETURN_ERROR(resizeVector(*val, srcSize));
+			err = field(key, val->data(), val->size());
+		} else if constexpr (isArray_v<T>) {
+			auto const &srcVal = value(key);
+			auto const srcSize = srcVal.size();
+			if (srcSize > val->size()) {
+				err = Error{1, "Input array is too long"};
+			} else {
+				err = field(key, val->data(), val->size());
+			}
+		} else if (targetValid()) {
+			auto const &jv = value(key);
+			if (jv.empty() || jv.isObject()) {
+				auto reader = child(key);
+				ModelHandlerInterface handler(reader);
+				err = model(&handler, val);
+			} else {
+				err = Error{1, "Type mismatch"};
+			}
+		}
+	} catch (Json::LogicError const &e) {
+		err = Error{1, "error reading JSON data"};
+	}
+	++m_fieldIt;
+	return err;
+}
+
+template<typename U, bool force>
+Error OrganicClawReader::field(CString const key, UnionView<U, force> val) noexcept {
+	Error err{};
+	if (targetValid()) {
+		auto const &jv = value(key);
+		if (jv.empty() || jv.isObject()) {
+			auto reader = child(key, val.idx());
+			ModelHandlerInterface handler(reader);
+			err = model(&handler, val.get());
+		} else {
+			err = Error{1, "Type mismatch"};
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+template<size_t L>
+Error OrganicClawReader::field(CString const key, BasicString<L> *val) noexcept {
+	Error err{};
+	if (targetValid()) {
+		auto const &jv = value(key);
+		if (jv.empty()) {
+			*val = BasicString<L>{};
+		} else if (jv.isString()) {
+			*val = jv.asString().c_str();
+		} else {
+			err = Error{1, "Type mismatch"};
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+template<size_t L>
+Error OrganicClawReader::field(CString const key, IString<L> *val) noexcept {
+	Error err{};
+	if (targetValid()) {
+		auto const &jv = value(key);
+		if (jv.empty()) {
+			*val = IString<L>{};
+		} else if (jv.isString()) {
+			*val = jv.asString().c_str();
+		} else {
+			err = Error{1, "Type mismatch"};
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+// array handler
+template<typename T>
+Error OrganicClawReader::field(CString const key, T *val, size_t valLen) noexcept {
+	auto const &srcVal = value(key);
+	if (!srcVal.isNull() && !srcVal.isArray()) {
+		return Error{1, "Type mismatch"};
+	}
+	auto srcSize = srcVal.size();
+	if (srcSize > valLen) {
+		return Error{1};
+	}
+	OrganicClawReader r(srcVal);
+	ModelHandlerInterface handler{r};
+	for (decltype(srcSize) i = 0; i < srcSize; ++i) {
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+		OX_RETURN_ERROR(handler.field("", &val[i]));
+OX_ALLOW_UNSAFE_BUFFERS_END
+	}
+	return {};
+}
+
+template<typename T>
+Error OrganicClawReader::field(CString const key, HashMap<String, T> *val) noexcept {
+	auto const &srcVal = value(key);
+	if (!srcVal.isObject()) {
+		return Error{1, "Type mismatch"};
+	}
+	auto keys = srcVal.getMemberNames();
+	auto srcSize = srcVal.size();
+	OrganicClawReader r(srcVal);
+	ModelHandlerInterface handler{r};
+	for (decltype(srcSize) i = 0; i < srcSize; ++i) {
+		auto const k = keys[i].c_str();
+		OX_RETURN_ERROR(handler.field(k, &val->operator[](k)));
+	}
+	return {};
+}
+
+Error readOC(BufferView const buff, auto &val) noexcept {
+	// OrganicClawReader constructor can throw, but readOC should return its errors.
+	try {
+		Json::Value doc;
+		Json::CharReaderBuilder parserBuilder;
+		auto parser = UPtr<Json::CharReader>(parserBuilder.newCharReader());
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+		if (!parser->parse(buff.data(), buff.data() + buff.size(), &doc, nullptr)) {
+OX_ALLOW_UNSAFE_BUFFERS_END
+			return Error{1, "Could not parse JSON"};
+		}
+		OrganicClawReader reader(buff.data(), buff.size());
+		ModelHandlerInterface handler(reader);
+		return model(&handler, &val);
+	} catch (Error const &err) {
+		return err;
+	} catch (...) {
+		return Error{1, "Unknown Error"};
+	}
+}
+
+template<typename T>
+Result<T> readOC(BufferView buff) noexcept {
+	Result<T> val;
+	OX_RETURN_ERROR(readOC(buff, val.value));
+	return val;
+}
+
+template<typename T>
+Result<T> readOC(StringViewCR json) noexcept {
+	return readOC<T>(BufferView{json.data(), json.size()});
+}
+
+}

src/oc/include/ox/oc/write.hpp

@@ -0,0 +1,285 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/def.hpp>
+
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+#include <json/json.h>
+OX_ALLOW_UNSAFE_BUFFERS_END
+
+#include <ox/model/fieldcounter.hpp>
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/types.hpp>
+#include <ox/model/typenamecatcher.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/hashmap.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/uuid.hpp>
+
+namespace ox {
+
+class OrganicClawWriter {
+
+	friend Result<Buffer> writeOC(const auto &val) noexcept;
+	friend Result<String> writeOCString(const auto &val) noexcept;
+
+	protected:
+		Json::Value m_json{Json::Value(Json::objectValue)};
+		Json::ArrayIndex m_fieldIt = 0;
+		int const m_unionIdx = -1;
+
+	public:
+		explicit OrganicClawWriter(int unionIdx = -1) noexcept;
+
+		explicit OrganicClawWriter(Json::Value json, int unionIdx = -1) noexcept;
+
+		Error field(CString const key, int8_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, int16_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, int32_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, int64_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+
+		Error field(CString const key, uint8_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, uint16_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, uint32_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(CString const key, uint64_t const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error field(char const*key, bool const *val) noexcept {
+			if (targetValid() && (*val || m_json.isArray())) {
+				value(key) = *val;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		template<typename U, bool force = true>
+		Error field(char const*, UnionView<U, force> val) noexcept;
+
+		template<typename T>
+		Error field(char const*key, HashMap<String, T> const *val) noexcept {
+			if (targetValid()) {
+				const auto &keys = val->keys();
+				OrganicClawWriter w;
+				ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler{w};
+				for (size_t i = 0; i < keys.size(); ++i) {
+					const auto k = keys[i].c_str();
+					if (k) [[likely]] {
+						OX_REQUIRE_M(value, val->at(k));
+						OX_RETURN_ERROR(handler.field(k, value));
+					}
+				}
+				value(key) = w.m_json;
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		template<size_t L>
+		Error field(char const*key, IString<L> const *val) noexcept {
+			if (targetValid() && val->size()) {
+				value(key) = val->c_str();
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		template<size_t L>
+		Error field(char const*key, BasicString<L> const *val) noexcept {
+			if (targetValid() && val->size()) {
+				value(key) = val->c_str();
+			}
+			++m_fieldIt;
+			return {};
+		}
+
+		Error fieldCString(CString, CString const *val, int len) noexcept;
+
+		Error fieldCString(CString name, CString const*val) noexcept;
+
+		Error field(CString key, UUID const *uuid) noexcept;
+
+		template<typename T>
+		Error field(CString, T const *val, size_t len) noexcept;
+
+		template<typename T>
+		Error field(CString, T const *val) noexcept;
+
+		template<typename T>
+		constexpr Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion) noexcept {
+			return {};
+		}
+
+		template<typename T>
+		constexpr Error setTypeInfo(
+				const char*,
+				int,
+				Vector<String> const&,
+				size_t) noexcept {
+			return {};
+		}
+
+		[[nodiscard]]
+		static constexpr auto opType() noexcept {
+			return OpType::Write;
+		}
+
+	private:
+		[[nodiscard]]
+		constexpr bool targetValid() const noexcept {
+			return static_cast<int>(m_fieldIt) == m_unionIdx || m_unionIdx == -1;
+		}
+
+		[[nodiscard]]
+		Json::Value &value(CString key) noexcept;
+
+};
+
+template<typename T>
+Error OrganicClawWriter::field(CString key, T const *val, size_t const len) noexcept {
+	if (targetValid() && len) {
+		OrganicClawWriter w((Json::Value(Json::arrayValue)));
+		ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler{w};
+		for (size_t i = 0; i < len; ++i) {
+OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+			OX_RETURN_ERROR(handler.field({}, &val[i]));
+OX_ALLOW_UNSAFE_BUFFERS_END
+		}
+		value(key) = w.m_json;
+	}
+	++m_fieldIt;
+	return {};
+}
+
+template<typename T>
+Error OrganicClawWriter::field(CString key, T const *val) noexcept {
+	if constexpr(is_integer_v<T>) {
+		if (targetValid() && (*val || m_json.isArray())) {
+			// the int type needs to be normalized because jsoncpp doesn't
+			// factor in every permutation unsigned long, etc.
+			if constexpr(is_signed_v<T>) {
+				value(key) = static_cast<Int<8 * sizeof(*val)>>(*val);
+			} else {
+				value(key) = static_cast<Uint<8 * sizeof(*val)>>(*val);
+			}
+		}
+	} else if constexpr(isVector_v<T> || isArray_v<T>) {
+		return field(key, val->data(), val->size());
+	} else if (val && targetValid()) {
+		OrganicClawWriter w;
+		ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler{w};
+		OX_RETURN_ERROR(model(&handler, val));
+		if (!w.m_json.empty() || m_json.isArray()) {
+			value(key) = w.m_json;
+		}
+	}
+	++m_fieldIt;
+	return {};
+}
+
+template<typename U, bool force>
+Error OrganicClawWriter::field(CString key, UnionView<U, force> val) noexcept {
+	if (targetValid()) {
+		OrganicClawWriter w(val.idx());
+		ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler{w};
+		OX_RETURN_ERROR(model(&handler, val.get()));
+		if (!w.m_json.isNull()) {
+			value(key) = w.m_json;
+		}
+	}
+	++m_fieldIt;
+	return {};
+}
+
+Result<Buffer> writeOC(auto const &val) noexcept {
+	OrganicClawWriter writer;
+	ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler(writer);
+	OX_RETURN_ERROR(model(&handler, &val));
+	Json::StreamWriterBuilder const jsonBuilder;
+	auto const str = Json::writeString(jsonBuilder, writer.m_json);
+	Result<Buffer> buff;
+	buff.value.resize(str.size() + 1);
+	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+	memcpy(buff.value.data(), str.data(), str.size() + 1);
+	OX_ALLOW_UNSAFE_BUFFERS_END
+	return buff;
+}
+
+Result<String> writeOCString(auto const &val) noexcept {
+	OrganicClawWriter writer;
+	ModelHandlerInterface<OrganicClawWriter, OpType::Write> handler(writer);
+	OX_RETURN_ERROR(model(&handler, &val));
+	Json::StreamWriterBuilder const jsonBuilder;
+	auto const str = Json::writeString(jsonBuilder, writer.m_json);
+	Result<String> buff;
+	buff.value.resize(str.size());
+	OX_ALLOW_UNSAFE_BUFFERS_BEGIN
+	memcpy(buff.value.data(), str.data(), str.size() + 1);
+	OX_ALLOW_UNSAFE_BUFFERS_END
+	return buff;
+}
+
+}

src/oc/src/read.cpp

@@ -0,0 +1,199 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/std/bit.hpp>
+#include <utility>
+
+#include <ox/oc/read.hpp>
+
+namespace ox {
+
+OrganicClawReader::OrganicClawReader(const uint8_t *buff, size_t const buffSize) {
+	auto json = reinterpret_cast<const char*>(buff);
+	auto jsonLen = ox::strnlen_s(json, buffSize);
+	Json::CharReaderBuilder parserBuilder;
+	auto parser = std::unique_ptr<Json::CharReader>(parserBuilder.newCharReader());
+	if (!parser->parse(json, json + jsonLen, &m_json, nullptr)) {
+		throw Exception(1, "Could not parse JSON");
+	}
+}
+
+OrganicClawReader::OrganicClawReader(CString const json, size_t const jsonLen) {
+	Json::CharReaderBuilder parserBuilder;
+	auto parser = std::unique_ptr<Json::CharReader>(parserBuilder.newCharReader());
+	if (!parser->parse(json, json + jsonLen, &m_json, nullptr)) {
+		throw Exception(1, "Could not parse JSON");
+	}
+}
+
+OrganicClawReader::OrganicClawReader(Json::Value json, int const unionIdx) noexcept:
+	m_json(std::move(json)),
+	m_unionIdx(unionIdx) {
+}
+
+Error OrganicClawReader::field(CString const key, bool *val) noexcept {
+	Error err{};
+	if (targetValid()) {
+		const auto &jv = value(key);
+		if (jv.empty()) {
+			*val = false;
+		} else if (jv.isBool()) {
+			*val = jv.asBool();
+		} else {
+			err = Error(1, "Type mismatch");
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+Error OrganicClawReader::fieldCString(CString const key, char *val, size_t const buffLen) noexcept {
+	Error err{};
+	CString begin = nullptr, end = nullptr;
+	const auto &jv = value(key);
+	if (targetValid()) {
+		if (jv.empty()) {
+			auto data = val;
+			if (data) {
+				data[0] = 0;
+			}
+		} else if (jv.isString()) {
+			jv.getString(&begin, &end);
+			const auto strSize = static_cast<size_t>(end - begin);
+			auto data = val;
+			if (strSize >= buffLen) {
+				err = Error(2, "String size exceeds capacity of destination");
+			} else {
+				memcpy(data, begin, static_cast<size_t>(strSize));
+				data[strSize] = 0;
+			}
+		} else {
+			err = Error(1, "Type mismatch");
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+Error OrganicClawReader::fieldCString(CString const key, char **val) noexcept {
+	Error err{};
+	CString begin = nullptr, end = nullptr;
+	const auto &jv = value(key);
+	auto &data = *val;
+	if (targetValid()) {
+		if (jv.empty()) {
+			if (data) {
+				data[0] = 0;
+			}
+		} else if (jv.isString()) {
+			jv.getString(&begin, &end);
+			const auto strSize = static_cast<size_t>(end - begin);
+			safeDelete(*val);
+			*val = new char[strSize + 1];
+			memcpy(data, begin, static_cast<size_t>(strSize));
+			data[strSize] = 0;
+		} else {
+			err = Error(1, "Type mismatch");
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+Error OrganicClawReader::fieldCString(CString const key, char **val, size_t const buffLen) noexcept {
+	Error err{};
+	CString begin = nullptr, end = nullptr;
+	const auto &jv = value(key);
+	if (targetValid()) {
+		if (jv.empty()) {
+			auto data = val;
+			if (data) {
+				data[0] = nullptr;
+			}
+		} else if (jv.isString()) {
+			jv.getString(&begin, &end);
+			const auto strSize = static_cast<size_t>(end - begin);
+			auto data = val;
+			if (strSize >= buffLen) {
+				safeDelete(*val);
+				*val = new char[strSize + 1];
+			}
+			memcpy(data, begin, static_cast<size_t>(strSize));
+			data[strSize] = nullptr;
+		} else {
+			err = Error(1, "Type mismatch");
+		}
+	}
+	++m_fieldIt;
+	return err;
+}
+
+Error OrganicClawReader::field(CString const key, UUID *val) noexcept {
+	UUIDStr str;
+	OX_RETURN_ERROR(field(key, &str));
+	return UUID::fromString(str).moveTo(*val);
+}
+
+Result<size_t> OrganicClawReader::arrayLength(CString const key, bool) noexcept {
+	const auto &jv = value(key);
+	if (jv.empty()) {
+		return 0;
+	}
+	if (jv.isArray()) {
+		return jv.size();
+	}
+	return Error(1, "Type mismatch");
+}
+
+[[nodiscard]]
+size_t OrganicClawReader::stringLength(CString const key) noexcept {
+	CString begin = nullptr, end = nullptr;
+	const auto &jv = value(key);
+	if (jv.empty()) {
+		return 0;
+	}
+	if (jv.isString()) {
+		jv.getString(&begin, &end);
+		return static_cast<size_t>(end - begin);
+	}
+	return Error(1, "Type mismatch");
+}
+
+OrganicClawReader OrganicClawReader::child(CString const key, int const unionIdx) noexcept {
+	return OrganicClawReader(value(key), unionIdx);
+}
+
+bool OrganicClawReader::fieldPresent(CString const key) noexcept {
+	return !m_json[key].empty();
+}
+
+int OrganicClawReader::whichFieldPresent(CString const name, ModelUnion const &u) const noexcept {
+	const auto &obj = m_json[name];
+	if (!obj.isObject()) {
+		return -1;
+	}
+	const auto &keys = obj.getMemberNames();
+	if (keys.size() != 1) {
+		return -1;
+	}
+	return u.getKeyIdx(keys.front().c_str());
+}
+
+Json::Value &OrganicClawReader::value(CString const key) noexcept {
+	if (m_json.isArray()) {
+		return m_json[m_fieldIt];
+	} else {
+		return m_json[key];
+	}
+}
+
+bool OrganicClawReader::targetValid() const noexcept {
+	return static_cast<int>(m_fieldIt) == m_unionIdx || m_unionIdx == -1;
+}
+
+}

src/oc/src/write.cpp

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/oc/write.hpp>
+
+namespace ox {
+
+OrganicClawWriter::OrganicClawWriter(int const unionIdx) noexcept: m_unionIdx(unionIdx) {
+}
+
+OrganicClawWriter::OrganicClawWriter(Json::Value json, int const unionIdx) noexcept:
+	m_json(std::move(json)),
+	m_unionIdx(unionIdx) {
+}
+
+Error OrganicClawWriter::fieldCString(const char *key, const char *const *val, int const len) noexcept {
+	if (targetValid() && len) {
+		value(key) = *val;
+	}
+	++m_fieldIt;
+	return {};
+}
+
+Error OrganicClawWriter::fieldCString(const char *key, const char *const *val) noexcept {
+	return fieldCString(key, const_cast<const char**>(val), static_cast<int>(ox::strlen(val)));
+}
+
+Error OrganicClawWriter::field(const char *key, UUID const *uuid) noexcept {
+	const auto uuidStr = uuid->toString();
+	if (targetValid() && uuidStr.size()) {
+		value(key) = uuidStr.c_str();
+	}
+	++m_fieldIt;
+	return {};
+}
+
+Json::Value &OrganicClawWriter::value(const char *key) noexcept {
+	if (m_json.isArray()) {
+		return m_json[m_fieldIt];
+	} else {
+		return m_json[key];
+	}
+}
+
+}

src/oc/test/CMakeLists.txt

@@ -0,0 +1,14 @@
+add_executable(
+	OcTest
+		tests.cpp
+)
+
+target_link_libraries(
+	OcTest
+		OxOrganicClaw
+)
+
+add_test("[ox/oc] Writer" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/OcTest OrganicClawWriter)
+add_test("[ox/oc] Reader" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/OcTest OrganicClawReader)
+add_test("[ox/oc] OrganicClawModelValue" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/OcTest OrganicClawModelValue)
+add_test("[ox/oc] OrganicClawDef" ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/OcTest OrganicClawDef)

src/oc/test/tests.cpp

@@ -0,0 +1,364 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#undef NDEBUG
+
+#include <map>
+
+#include <ox/model/model.hpp>
+#include <ox/oc/oc.hpp>
+#include <ox/std/std.hpp>
+
+template<typename T>
+union U {
+	T t;
+	int i;
+};
+
+U<short> u;
+
+union TestUnion {
+	static constexpr auto TypeName = "TestUnion";
+	static constexpr auto TypeVersion = 1;
+	bool Bool;
+	uint32_t Int = 5;
+	char *String;
+};
+
+struct TestStructNest {
+	static constexpr auto TypeName = "TestStructNest";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	uint32_t Int = 0;
+	ox::IString<32> String = "";
+};
+
+struct TestStruct {
+	static constexpr auto TypeName = "TestStruct";
+	static constexpr auto TypeVersion = 1;
+	bool Bool = false;
+	int32_t Int = 0;
+	int32_t Int1 = 0;
+	int32_t Int2 = 0;
+	int32_t Int3 = 0;
+	int32_t Int4 = 0;
+	int32_t Int5 = 0;
+	int32_t Int6 = 0;
+	int32_t Int7 = 0;
+	int32_t Int8 = 0;
+	int unionIdx = 1;
+	TestUnion Union;
+	ox::String String{""};
+	uint32_t List[4] = {0, 0, 0, 0};
+	ox::HashMap<ox::String, int> Map;
+	TestStructNest EmptyStruct;
+	TestStructNest Struct;
+
+	TestStruct() noexcept = default;
+
+	TestStruct(TestStruct &&other) noexcept;
+
+	constexpr ~TestStruct() noexcept {
+		if (unionIdx == 2) {
+			ox::safeDelete(Union.String);
+		}
+	}
+
+	constexpr TestStruct &operator=(TestStruct&&) noexcept;
+
+};
+
+constexpr ox::Error model(auto *io, ox::CommonPtrWith<TestUnion> auto *obj) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestUnion>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->fieldCString("String", &obj->String));
+	return ox::Error(0);
+}
+
+constexpr ox::Error model(auto *io, ox::CommonPtrWith<TestStructNest> auto *obj) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestStructNest>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->field("String", &obj->String));
+	return ox::Error(0);
+}
+
+constexpr ox::Error model(auto *io, ox::CommonPtrWith<TestStruct> auto *obj) noexcept {
+	OX_RETURN_ERROR(io->template setTypeInfo<TestStruct>());
+	OX_RETURN_ERROR(io->field("Bool", &obj->Bool));
+	OX_RETURN_ERROR(io->field("Int", &obj->Int));
+	OX_RETURN_ERROR(io->field("Int1", &obj->Int1));
+	OX_RETURN_ERROR(io->field("Int2", &obj->Int2));
+	OX_RETURN_ERROR(io->field("Int3", &obj->Int3));
+	OX_RETURN_ERROR(io->field("Int4", &obj->Int4));
+	OX_RETURN_ERROR(io->field("Int5", &obj->Int5));
+	OX_RETURN_ERROR(io->field("Int6", &obj->Int6));
+	OX_RETURN_ERROR(io->field("Int7", &obj->Int7));
+	OX_RETURN_ERROR(io->field("Int8", &obj->Int8));
+	OX_RETURN_ERROR(io->field("unionIdx", &obj->unionIdx));
+	if (io->opType() == ox::OpType::Reflect) {
+		OX_RETURN_ERROR(io->field("Union", ox::UnionView{&obj->Union, 0}));
+	} else {
+		OX_RETURN_ERROR(io->field("Union", ox::UnionView{&obj->Union, obj->unionIdx}));
+	}
+	OX_RETURN_ERROR(io->field("String", &obj->String));
+	OX_RETURN_ERROR(io->field("List", obj->List, 4));
+	OX_RETURN_ERROR(io->field("Map", &obj->Map));
+	OX_RETURN_ERROR(io->field("EmptyStruct", &obj->EmptyStruct));
+	OX_RETURN_ERROR(io->field("Struct", &obj->Struct));
+	return ox::Error(0);
+}
+
+TestStruct::TestStruct(TestStruct &&other) noexcept {
+	ox::moveModel(this, &other);
+}
+
+constexpr TestStruct &TestStruct::operator=(TestStruct &&other) noexcept {
+	ox::moveModel(this, &other);
+	return *this;
+}
+
+const std::map<ox::StringView, ox::Error(*)()> tests = {
+	{
+		{
+			"OrganicClawWriter",
+			[] {
+				// This test doesn't confirm much, but it does show that the writer
+				// doesn't segfault
+				TestStruct ts;
+				return ox::writeOC(ts).error;
+			}
+		},
+		{
+			"OrganicClawReader",
+			[] {
+				TestStruct testIn;
+				testIn.Bool = true;
+				testIn.Int = 42;
+				testIn.Union.Int = 52;
+				testIn.String = "Test String 1";
+				testIn.List[0] = 1;
+				testIn.List[1] = 2;
+				testIn.List[2] = 3;
+				testIn.List[3] = 4;
+				testIn.Map["asdf"] = 93;
+				testIn.Map["aoeu"] = 94;
+				testIn.Struct.Bool = false;
+				testIn.Struct.Int = 300;
+				testIn.Struct.String = "Test String 2";
+
+				auto [oc, writeErr] = ox::writeOC(testIn);
+				oxAssert(writeErr, "writeOC failed");
+				oxOutf("{}\n", oc.data());
+				auto [testOut, readErr] = ox::readOC<TestStruct>(oc.data());
+				oxAssert(readErr, "readOC failed");
+
+				oxAssert(testIn.Bool               == testOut.Bool, "Bool value mismatch");
+				oxAssert(testIn.Int                == testOut.Int, "Int value mismatch");
+				oxAssert(testIn.Int1               == testOut.Int1, "Int1 value mismatch");
+				oxAssert(testIn.Int2               == testOut.Int2, "Int2 value mismatch");
+				oxAssert(testIn.Int3               == testOut.Int3, "Int3 value mismatch");
+				oxAssert(testIn.Int4               == testOut.Int4, "Int4 value mismatch");
+				oxAssert(testIn.Int5               == testOut.Int5, "Int5 value mismatch");
+				oxAssert(testIn.Int6               == testOut.Int6, "Int6 value mismatch");
+				oxAssert(testIn.Int7               == testOut.Int7, "Int7 value mismatch");
+				oxAssert(testIn.Int8               == testOut.Int8, "Int8 value mismatch");
+				oxAssert(testIn.Union.Int          == testOut.Union.Int, "Union.Int value mismatch");
+				oxAssert(testIn.String             == testOut.String, "String value mismatch");
+				oxAssert(testIn.List[0]            == testOut.List[0], "List[0] value mismatch");
+				oxAssert(testIn.List[1]            == testOut.List[1], "List[1] value mismatch");
+				oxAssert(testIn.List[2]            == testOut.List[2], "List[2] value mismatch");
+				oxAssert(testIn.List[3]            == testOut.List[3], "List[3] value mismatch");
+				oxAssert(testIn.Map["asdf"]        == testOut.Map["asdf"], "Map[\"asdf\"] value mismatch");
+				oxAssert(testIn.Map["aoeu"]        == testOut.Map["aoeu"], "Map[\"aoeu\"] value mismatch");
+				oxAssert(testIn.EmptyStruct.Bool   == testOut.EmptyStruct.Bool, "EmptyStruct.Bool value mismatch");
+				oxAssert(testIn.EmptyStruct.Int    == testOut.EmptyStruct.Int, "EmptyStruct.Int value mismatch");
+				oxAssert(testIn.EmptyStruct.String == testOut.EmptyStruct.String, "EmptyStruct.String value mismatch");
+				oxAssert(testIn.Struct.Int         == testOut.Struct.Int, "Struct.Int value mismatch");
+				oxAssert(testIn.Struct.String      == testOut.Struct.String, "Struct.String value mismatch");
+				oxAssert(testIn.Struct.Bool        == testOut.Struct.Bool, "Struct.Bool value mismatch");
+
+				return ox::Error(0);
+			}
+		},
+
+		{
+			"OrganicClawModelValue",
+			[] {
+		   ox::Buffer dataBuff;
+		   TestStruct testIn;
+		   testIn.Bool = true;
+		   testIn.Int = 42;
+		   testIn.String = "Test String 1";
+		   testIn.List[0] = 1;
+		   testIn.List[1] = 2;
+		   testIn.List[2] = 3;
+		   testIn.List[3] = 4;
+		   testIn.Struct.Bool = false;
+		   testIn.Struct.Int = 300;
+		   testIn.Struct.String = "Test String 2";
+		   testIn.unionIdx = 1;
+		   testIn.Union.Int = 93;
+		   oxAssert(ox::writeOC(testIn).moveTo(dataBuff), "Data generation failed");
+		   ox::TypeStore typeStore;
+		   auto type = ox::buildTypeDef(typeStore, testIn);
+		   oxAssert(type.error, "Descriptor write failed");
+		   ox::ModelObject testOut;
+		   OX_RETURN_ERROR(testOut.setType(type.value));
+		   oxAssert(ox::readOC(dataBuff, testOut), "Data read failed");
+		   oxAssert(testOut.get("Int").unwrap()->get<int>() == testIn.Int, "testOut.Int failed");
+		   oxAssert(testOut.get("Bool").unwrap()->get<bool>() == testIn.Bool, "testOut.Bool failed");
+		   oxAssert(testOut.get("String").unwrap()->get<ox::String>() == testIn.String, "testOut.String failed");
+		   auto &testOutStruct = testOut.get("Struct").unwrap()->get<ox::ModelObject>();
+		   auto &testOutUnion = testOut.get("Union").unwrap()->get<ox::ModelUnion>();
+		   auto &testOutList = testOut.get("List").unwrap()->get<ox::ModelValueVector>();
+		   auto testOutStructCopy = testOut.get("Struct").unwrap()->get<ox::ModelObject>();
+		   auto testOutUnionCopy = testOut.get("Union").unwrap()->get<ox::ModelUnion>();
+		   auto testOutListCopy = testOut.get("List").unwrap()->get<ox::ModelValueVector>();
+		   oxAssert(testOutStruct.typeName() == TestStructNest::TypeName, "ModelObject TypeName failed");
+		   oxAssert(testOutStruct.typeVersion() == TestStructNest::TypeVersion, "ModelObject TypeVersion failed");
+		   oxAssert(testOutStruct.get("Bool").unwrap()->get<bool>() == testIn.Struct.Bool, "testOut.Struct.Bool failed");
+		   oxAssert(testOutStruct.get("String").unwrap()->get<ox::String>() == testIn.Struct.String.c_str(), "testOut.Struct.String failed");
+		   oxAssert(testOut.get("unionIdx").unwrap()->get<int>() == testIn.unionIdx, "testOut.unionIdx failed");
+		   oxAssert(testOutUnion.unionIdx() == testIn.unionIdx, "testOut.Union idx wrong");
+		   oxAssert(testOutUnion.get("Int").unwrap()->get<uint32_t>() == testIn.Union.Int, "testOut.Union.Int failed");
+		   oxAssert(testOutList[0].get<uint32_t>() == testIn.List[0], "testOut.List[0] failed");
+		   oxAssert(testOutList[1].get<uint32_t>() == testIn.List[1], "testOut.Struct.List[1] failed");
+		   oxAssert(testOutStructCopy.get("Bool").unwrap()->get<bool>() == testIn.Struct.Bool, "testOut.Struct.Bool (copy) failed");
+		   oxAssert(testOutStructCopy.get("String").unwrap()->get<ox::String>() == testIn.Struct.String.c_str(), "testOut.Struct.String (copy) failed");
+		   oxAssert(testOutListCopy[0].get<uint32_t>() == testIn.List[0], "testOut.Struct.List[0] (copy) failed");
+		   oxAssert(testOutListCopy[1].get<uint32_t>() == testIn.List[1], "testOut.Struct.List[1] (copy) failed");
+		   return ox::Error(0);
+		   }
+		},
+
+		{
+			"OrganicClawDef",
+			[] {
+				TestStruct testIn, testOut;
+
+				testIn.Bool = true;
+				testIn.Int = 42;
+				testIn.String = "Test String 1";
+				testIn.List[0] = 1;
+				testIn.List[1] = 2;
+				testIn.List[2] = 3;
+				testIn.List[3] = 4;
+				testIn.Struct.Bool = false;
+				testIn.Struct.Int = 300;
+				testIn.Struct.String = "Test String 2";
+
+				auto [oc, ocErr] = ox::writeOC(testIn);
+				oxAssert(ocErr, "Data generation failed");
+				ox::TypeStore typeStore;
+				auto type = ox::buildTypeDef(typeStore, testIn);
+				oxAssert(type.error, "Descriptor write failed");
+				OX_RETURN_ERROR(ox::walkModel<ox::OrganicClawReader>(type.value, oc.data(), oc.size(),
+					[](const ox::Vector<ox::FieldName>&, const ox::Vector<ox::String>&, const ox::DescriptorField &f,
+					   ox::OrganicClawReader *rdr) -> ox::Error {
+						auto fieldName = f.fieldName.c_str();
+						switch (f.type->primitiveType) {
+							case ox::PrimitiveType::UnsignedInteger:
+								oxOutf("{}:\tuint{}_t:\t", fieldName, f.type->length * 8);
+								switch (f.type->length) {
+									case 1: {
+										uint8_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 2: {
+										uint16_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 4: {
+										uint32_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 8: {
+										uint64_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+								}
+								oxOut("\n");
+								break;
+							case ox::PrimitiveType::SignedInteger:
+								oxOutf("{}:\tint{}_t:\t", fieldName, f.type->length * 8);
+								switch (f.type->length) {
+									case 1: {
+										int8_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 2: {
+										int16_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 4: {
+										int32_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+									case 8: {
+										int64_t i = {};
+										oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+										oxOutf("{}", i);
+										break;
+									}
+								}
+								oxOut("\n");
+								break;
+							case ox::PrimitiveType::Bool: {
+								bool i = {};
+								oxAssert(rdr->field(fieldName, &i), "Walking model failed.");
+								oxOutf("{}:\tbool:\t{}\n", fieldName, i ? "true" : "false");
+								break;
+							}
+							case ox::PrimitiveType::String: {
+								ox::Vector<char> v(rdr->stringLength(fieldName) + 1);
+								oxAssert(rdr->fieldCString(fieldName, v.data(), v.size()), "Walking model failed.");
+								oxOutf("{}:\tstring:\t{}\n", fieldName, v.data());
+								break;
+							}
+							case ox::PrimitiveType::Struct:
+								break;
+							case ox::PrimitiveType::Union:
+								break;
+						}
+						return ox::Error(0);
+					}
+				));
+				return ox::Error(0);
+			}
+		},
+	}
+};
+
+int main(int argc, const char **args) {
+	if (argc < 2) {
+		oxError("Must specify test to run");
+	}
+	auto const testName = args[1];
+	auto const func = tests.find(testName);
+	if (func != tests.end()) {
+		oxAssert(func->second(), "Test returned Error");
+		return 0;
+	}
+	return -1;
+}

src/preloader/CMakeLists.txt

@@ -0,0 +1,36 @@
+
+add_library(
+	OxPreloader
+		src/preloader.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxPreloader PRIVATE -Wsign-conversion)
+	target_compile_options(OxPreloader PRIVATE -Wconversion)
+endif()
+
+target_link_libraries(
+	OxPreloader PUBLIC
+		OxClaw
+		OxModel
+		OxStd
+)
+
+target_include_directories(
+	OxPreloader PUBLIC
+		include
+)
+
+install(
+	DIRECTORY
+		include/ox
+	DESTINATION
+		include
+)
+
+install(
+	TARGETS
+		OxPreloader
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)

src/preloader/include/ox/preloader/alignmentcatcher.hpp

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+
+namespace ox {
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t alignOf(const T &v) noexcept;
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t sizeOf(const T *t) noexcept;
+
+template<typename PlatSpec>
+struct AlignmentCatcher: public ModelHandlerBase<AlignmentCatcher<PlatSpec>, OpType::Reflect> {
+	std::size_t biggestAlignment = 1;
+
+	template<typename T>
+	constexpr ox::Error setTypeInfo(
+			const char* = T::TypeName,
+			int = T::TypeVersion) noexcept {
+		return {};
+	}
+
+	template<typename T>
+	constexpr ox::Error setTypeInfo(
+			const char*,
+			int,
+			const Vector<String>&,
+			std::size_t) noexcept {
+		return {};
+	}
+
+	template<typename T, bool force>
+	constexpr ox::Error field(StringViewCR name, const UnionView<T, force> val) noexcept {
+		return field(name, val.get());
+	}
+
+	template<typename T>
+	constexpr ox::Error field(StringViewCR, const T *val) noexcept {
+		if constexpr(ox::is_pointer_v<T> || ox::is_integer_v<T>) {
+			biggestAlignment = ox::max(biggestAlignment, PlatSpec::alignOf(*val));
+		} else {
+			biggestAlignment = ox::max(biggestAlignment, alignOf<PlatSpec>(*val));
+		}
+		return {};
+	}
+
+	template<typename T>
+	constexpr ox::Error field(StringViewCR, const T *val, std::size_t cnt) noexcept {
+		for (std::size_t i = 0; i < cnt; ++i) {
+			OX_RETURN_ERROR(field(nullptr, &val[i]));
+		}
+		return {};
+	}
+
+};
+
+}

src/preloader/include/ox/preloader/platspecs.hpp

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/serialize.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/typetraits.hpp>
+
+#include "alignmentcatcher.hpp"
+#include "sizecatcher.hpp"
+
+namespace ox {
+
+struct NativePlatSpec {
+	static constexpr std::size_t RomStart = 1024;
+	using PtrType = uintptr_t;
+	using size_t = std::size_t;
+
+	template<typename T>
+	[[nodiscard]]
+	static constexpr std::size_t alignOf(const T &v) noexcept {
+		if constexpr(ox::is_integral_v<T>) {
+			return alignof(T);
+		} else if constexpr(ox::is_pointer_v<T>) {
+			const PtrType p = 0;
+			return alignOf(p);
+		} else {
+			AlignmentCatcher<NativePlatSpec> c;
+			oxAssert(model(c.interface(), &v), "Could not get alignment for type");
+			return c.biggestAlignment;
+		}
+	}
+
+	[[nodiscard]]
+	static constexpr auto correctEndianness(auto v) noexcept {
+		return v;
+	}
+};
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t alignOf(const T &v) noexcept {
+	if constexpr(ox::is_integral_v<T>) {
+		return alignof(T);
+	} else if constexpr(ox::is_pointer_v<T>) {
+		typename PlatSpec::PtrType p = 0;
+		return PlatSpec::alignOf(p);
+	} else {
+		AlignmentCatcher<PlatSpec> c;
+		oxAssert(model(c.interface(), &v), "Could not get alignment for type");
+		return c.biggestAlignment;
+	}
+}
+
+}

src/preloader/include/ox/preloader/preloader.hpp

@@ -0,0 +1,414 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/std/array.hpp>
+#include <ox/std/buffer.hpp>
+#include <ox/std/byteswap.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/memops.hpp>
+#include <ox/std/memory.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+#include <ox/std/typetraits.hpp>
+#include <ox/std/units.hpp>
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/modelvalue.hpp>
+
+#include "platspecs.hpp"
+
+namespace ox {
+
+template<typename PlatSpec>
+class Preloader;
+
+template<typename PlatSpec>
+class Preloader: public ModelHandlerBase<Preloader<PlatSpec>, OpType::Reflect> {
+	private:
+		using PtrType = typename PlatSpec::PtrType;
+		static constexpr auto PtrSize = sizeof(PtrType);
+		class UnionIdxTracker {
+			private:
+				int m_unionIdx = -1;
+				int m_it = 0;
+			public:
+				constexpr UnionIdxTracker() noexcept = default;
+				constexpr explicit UnionIdxTracker(int idx) noexcept: m_unionIdx(idx) {}
+				constexpr auto checkAndIterate() noexcept {
+					return m_unionIdx == -1 || m_it++ == m_unionIdx;
+				}
+		};
+		ox::Buffer m_buff;
+		ox::BufferWriter m_writer;
+		// list of all the places where ptrs were written to buffer
+		struct PtrPair {
+			std::size_t loc = 0;
+			typename PlatSpec::PtrType value = 0;
+			constexpr PtrPair() noexcept = default;
+			constexpr PtrPair(std::size_t pLoc, typename PlatSpec::PtrType pValue) noexcept:
+				loc(pLoc), value(pValue) {}
+		};
+		ox::Vector<PtrPair> m_ptrs;
+		ox::Vector<UnionIdxTracker, 8> m_unionIdx = {{}};
+		class AllocStackItem {
+			public:
+				PtrType restore = 0;
+				ox::ios_base::seekdir seekdir = ox::ios_base::end;
+				constexpr AllocStackItem(PtrType pRestore, ox::ios_base::seekdir pSeekdir = ox::ios_base::end) noexcept:
+						restore(pRestore), seekdir(pSeekdir) {}
+		};
+		ox::Vector<AllocStackItem, 8> m_allocStack;
+		ox::Vector<size_t> m_allocStart{};
+
+		constexpr Preloader() noexcept: m_writer(&m_buff) {}
+
+	public:
+		Preloader(const Preloader &src) = delete;
+		Preloader(Preloader &&src) = delete;
+		const Preloader &operator=(const Preloader &src) = delete;
+		const Preloader &operator=(Preloader &&src) = delete;
+
+		constexpr static ox::Result<ox::UPtr<Preloader>> make(ox::ios_base::seekdir anchor = ox::ios_base::cur,
+		                                                           std::size_t sz = 0) noexcept;
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion) noexcept {
+			return {};
+		}
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char*,
+				int,
+				const Vector<String>&,
+				std::size_t) noexcept {
+			return {};
+		}
+
+		template<typename U, bool force>
+		constexpr ox::Error field(StringViewCR, ox::UnionView<U, force> val) noexcept;
+
+		template<typename T>
+		constexpr ox::Error field(StringViewCR, const T *val) noexcept;
+
+		template<std::size_t SmallStringSize>
+		constexpr ox::Error field(StringViewCR, const ox::BasicString<SmallStringSize> *val) noexcept;
+
+		template<typename T, std::size_t sz>
+		constexpr ox::Error field(StringViewCR, const ox::Array<T, sz> *valArray) noexcept;
+
+		template<typename T>
+		constexpr ox::Error field(StringViewCR, const T **val, std::size_t cnt) noexcept;
+
+		constexpr ox::Result<std::size_t> startAlloc(size_t sz, size_t align) noexcept;
+
+		constexpr ox::Result<std::size_t> startAlloc(size_t sz, size_t align, std::size_t restore) noexcept;
+
+		constexpr ox::Error endAlloc() noexcept;
+
+		constexpr ox::Error offsetPtrs(std::size_t offset) noexcept;
+
+		[[nodiscard]]
+		constexpr auto &buff() const noexcept {
+			return m_buff;
+		}
+
+		template<typename T>
+		constexpr ox::Error pad(const T*) noexcept;
+
+	private:
+		constexpr ox::Error fieldVector(StringViewCR name, const ox::ModelValueVector *val) noexcept;
+
+		template<typename T, std::size_t SmallVectorSize, typename Allocator>
+		constexpr ox::Error fieldVector(StringViewCR, const ox::Vector<T, SmallVectorSize, Allocator> *val) noexcept;
+
+		constexpr ox::Error fieldVector(StringViewCR, const auto *val, ox::VectorMemMap<PlatSpec> vecVal) noexcept;
+
+		constexpr ox::Error fieldArray(StringViewCR name, ox::ModelValueArray const*val) noexcept;
+
+		constexpr bool unionCheckAndIt() noexcept;
+
+		[[nodiscard]]
+		constexpr size_t calcPadding(size_t align) const noexcept;
+};
+
+template<typename PlatSpec>
+constexpr ox::Result<ox::UPtr<Preloader<PlatSpec>>>
+Preloader<PlatSpec>::make(ox::ios_base::seekdir anchor, std::size_t sz) noexcept {
+	auto p = ox::UPtr<Preloader>(new Preloader);
+	if (const auto err = p->m_writer.seekp(0, anchor)) {
+		return {std::move(p), err};
+	}
+	if (const auto err = p->m_writer.write(nullptr, sz)) {
+		return {std::move(p), err};
+	}
+	if (const auto err = p->m_writer.seekp(p->m_writer.tellp() - sz)) {
+		return {std::move(p), err};
+	}
+	return p;
+}
+
+template<typename PlatSpec>
+template<typename U, bool force>
+constexpr ox::Error Preloader<PlatSpec>::field(StringViewCR, const ox::UnionView<U, force> val) noexcept {
+	if (!unionCheckAndIt()) {
+		return {};
+	}
+	OX_RETURN_ERROR(pad(val.get()));
+	m_unionIdx.emplace_back(val.idx());
+	const auto err = preload<PlatSpec, U>(this, val.get());
+	m_unionIdx.pop_back();
+	return err;
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error Preloader<PlatSpec>::field(StringViewCR name, const T *val) noexcept {
+	if (!unionCheckAndIt()) {
+		return {};
+	}
+	OX_RETURN_ERROR(pad(val));
+	if constexpr(ox::is_integral_v<T>) {
+		return ox::serialize(m_writer, PlatSpec::correctEndianness(*val));
+	} else if constexpr(ox::is_pointer_v<T>) {
+		const PtrType a = startAlloc(sizeOf<PlatSpec>(val), alignOf<PlatSpec>(*val), m_writer.tellp()) + PlatSpec::RomStart;
+		OX_RETURN_ERROR(field(name, *val));
+		OX_RETURN_ERROR(endAlloc());
+		return ox::serialize(m_writer, PlatSpec::correctEndianness(a));
+	} else if constexpr(ox::isVector_v<T>) {
+		return fieldVector(name, val);
+	} else if constexpr(ox::is_same_v<T, ox::ModelValueVector>) {
+		val->types();
+		return fieldVector(name, val);
+	} else if constexpr(ox::is_same_v<T, ox::ModelValueArray>) {
+		return fieldArray(name, val);
+	} else {
+		m_unionIdx.emplace_back(-1);
+		const auto out = preload<PlatSpec, T>(this, val);
+		m_unionIdx.pop_back();
+		return out;
+	}
+}
+
+template<typename PlatSpec>
+template<std::size_t SmallStringSize>
+constexpr ox::Error Preloader<PlatSpec>::field(StringViewCR, const ox::BasicString<SmallStringSize> *val) noexcept {
+	if (!unionCheckAndIt()) {
+		return {};
+	}
+	using VecMap = ox::VectorMemMap<PlatSpec>;
+	const auto sz = val->bytes();
+	VecMap vecVal{
+		.smallVecSize = SmallStringSize,
+		.size = PlatSpec::correctEndianness(static_cast<typename PlatSpec::size_t>(sz)),
+		.cap = PlatSpec::correctEndianness(static_cast<typename PlatSpec::size_t>(sz)),
+	};
+	OX_RETURN_ERROR(pad(&vecVal));
+	const auto restore = m_writer.tellp();
+	std::size_t a = 0;
+	if (sz && sz >= SmallStringSize) {
+		OX_RETURN_ERROR(ox::allocate(m_writer, sz).moveTo(a));
+	} else {
+		a = restore;
+	}
+	vecVal.items = PlatSpec::correctEndianness(static_cast<PtrType>(a) + PlatSpec::RomStart);
+	OX_RETURN_ERROR(m_writer.seekp(a));
+	OX_RETURN_ERROR(m_writer.write(val->data(), sz));
+	OX_RETURN_ERROR(m_writer.seekp(restore));
+	OX_RETURN_ERROR(serialize(m_writer, vecVal));
+	m_ptrs.emplace_back(restore + offsetof(VecMap, items), vecVal.items);
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T, std::size_t sz>
+constexpr ox::Error Preloader<PlatSpec>::field(StringViewCR name, const ox::Array<T, sz> *val) noexcept {
+	if (!unionCheckAndIt()) {
+		return {};
+	}
+	OX_RETURN_ERROR(pad(&(*val)[0]));
+	// serialize the Array elements
+	if constexpr(sz) {
+		m_unionIdx.emplace_back(-1);
+		for (std::size_t i = 0; i < val->size(); ++i) {
+			OX_RETURN_ERROR(this->interface()->field(name, &(*val)[i]));
+		}
+		m_unionIdx.pop_back();
+	}
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error Preloader<PlatSpec>::field(StringViewCR, const T **val, std::size_t cnt) noexcept {
+	if (!unionCheckAndIt()) {
+		return {};
+	}
+	if (cnt) {
+		OX_RETURN_ERROR(pad(*val));
+		// serialize the array
+		m_unionIdx.emplace_back(-1);
+		for (std::size_t i = 0; i < cnt; ++i) {
+			OX_RETURN_ERROR(this->interface()->field(nullptr, &val[i]));
+		}
+		m_unionIdx.pop_back();
+	}
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr ox::Result<std::size_t> Preloader<PlatSpec>::startAlloc(size_t sz, size_t align) noexcept {
+	m_allocStack.emplace_back(static_cast<typename PlatSpec::PtrType>(m_writer.tellp()));
+	OX_RETURN_ERROR(m_writer.seekp(0, ox::ios_base::end));
+	auto const padding = calcPadding(align);
+	OX_REQUIRE_M(a, ox::allocate(m_writer, sz + padding));
+	a += padding;
+	OX_RETURN_ERROR(m_writer.seekp(a));
+	m_allocStart.push_back(a);
+	return a;
+}
+
+template<typename PlatSpec>
+constexpr ox::Result<std::size_t> Preloader<PlatSpec>::startAlloc(
+		std::size_t sz, size_t align, std::size_t restore) noexcept {
+	m_allocStack.emplace_back(restore, ox::ios_base::beg);
+	OX_RETURN_ERROR(m_writer.seekp(0, ox::ios_base::end));
+	auto const padding = calcPadding(align);
+	OX_REQUIRE_M(a, ox::allocate(m_writer, sz + padding));
+	a += padding;
+	OX_RETURN_ERROR(m_writer.seekp(a));
+	m_allocStart.push_back(a);
+	return a;
+}
+
+template<typename PlatSpec>
+constexpr ox::Error Preloader<PlatSpec>::endAlloc() noexcept {
+	if (m_allocStack.empty()) {
+		return m_writer.seekp(0, ox::ios_base::end);
+	}
+	const auto &si = *m_allocStack.back().unwrap();
+	OX_RETURN_ERROR(m_writer.seekp(static_cast<ox::ssize_t>(si.restore), si.seekdir));
+	m_allocStack.pop_back();
+	m_allocStart.pop_back();
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr ox::Error Preloader<PlatSpec>::offsetPtrs(std::size_t offset) noexcept {
+	for (const auto &p : m_ptrs) {
+		OX_RETURN_ERROR(m_writer.seekp(p.loc));
+		const auto val = PlatSpec::template correctEndianness<typename PlatSpec::PtrType>(
+				static_cast<typename PlatSpec::PtrType>(p.value + offset));
+		OX_RETURN_ERROR(ox::serialize(m_writer, val));
+	}
+	OX_RETURN_ERROR(m_writer.seekp(0, ox::ios_base::end));
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error Preloader<PlatSpec>::pad(const T *v) noexcept {
+	const auto a = alignOf<PlatSpec>(*v);
+	const auto excess = m_writer.tellp() % a;
+	if (excess) {
+		return m_writer.write(nullptr, a - excess);
+	} else {
+		return {};
+	}
+}
+
+template<typename PlatSpec>
+constexpr ox::Error Preloader<PlatSpec>::fieldVector(
+		StringViewCR name, const ox::ModelValueVector *val) noexcept {
+	// serialize the Vector
+	ox::VectorMemMap<PlatSpec> vecVal{
+			.size = PlatSpec::correctEndianness(static_cast<typename PlatSpec::size_t>(val->size())),
+			.cap = PlatSpec::correctEndianness(static_cast<typename PlatSpec::size_t>(val->size())),
+	};
+	return fieldVector(name, val, vecVal);
+}
+
+template<typename PlatSpec>
+template<typename T, std::size_t SmallVectorSize, typename Allocator>
+constexpr ox::Error Preloader<PlatSpec>::fieldVector(
+		StringViewCR name, const ox::Vector<T, SmallVectorSize, Allocator> *val) noexcept {
+	// serialize the Vector
+	ox::VectorMemMap<PlatSpec> vecVal{
+		.smallVecSize = SmallVectorSize * sizeOf<PlatSpec>(static_cast<T*>(nullptr)),
+		.size = PlatSpec::correctEndianness(
+				static_cast<typename PlatSpec::size_t>(val->size())),
+		.cap = PlatSpec::correctEndianness(
+				static_cast<typename PlatSpec::size_t>(val->size())),
+	};
+	return fieldVector(name, val, vecVal);
+}
+
+template<typename PlatSpec>
+constexpr ox::Error Preloader<PlatSpec>::fieldVector(
+		StringViewCR, const auto *val, ox::VectorMemMap<PlatSpec> vecVal) noexcept {
+	OX_RETURN_ERROR(pad(&vecVal));
+	const auto vecValPt = m_writer.tellp();
+	// serialize the Vector elements
+	if (val->size()) {
+		const auto sz = sizeOf<PlatSpec>(&(*val)[0]) * val->size();
+		const auto align = alignOf<PlatSpec>((*val)[0]);
+		OX_RETURN_ERROR(m_writer.seekp(0, ox::ios_base::end));
+		auto const padding = calcPadding(align);
+		OX_REQUIRE_M(p, ox::allocate(m_writer, sz + padding));
+		p += padding;
+		OX_RETURN_ERROR(m_writer.seekp(p));
+		m_unionIdx.emplace_back(-1);
+		for (std::size_t i = 0; i < val->size(); ++i) {
+			OX_RETURN_ERROR(this->interface()->field(nullptr, &val->operator[](i)));
+		}
+		m_unionIdx.pop_back();
+		vecVal.items = PlatSpec::correctEndianness(
+				static_cast<typename PlatSpec::size_t>(p + PlatSpec::RomStart));
+		OX_RETURN_ERROR(m_writer.seekp(vecValPt));
+	} else {
+		vecVal.items = 0;
+	}
+	// serialize the Vector
+	OX_RETURN_ERROR(serialize(m_writer, vecVal));
+	m_ptrs.emplace_back(m_writer.tellp() - PtrSize, vecVal.items);
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr ox::Error Preloader<PlatSpec>::fieldArray(StringViewCR, ox::ModelValueArray const*val) noexcept {
+	OX_RETURN_ERROR(pad(&(*val)[0]));
+	for (auto const&v : *val) {
+		OX_RETURN_ERROR(this->interface()->field({}, &v));
+	}
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr bool Preloader<PlatSpec>::unionCheckAndIt() noexcept {
+	auto &u = *m_unionIdx.back().unwrap();
+	return u.checkAndIterate();
+}
+
+template<typename PlatSpec>
+constexpr size_t Preloader<PlatSpec>::calcPadding(size_t align) const noexcept {
+	auto const excess = m_writer.tellp() % align;
+	return (align * (excess != 0)) - excess;
+}
+
+template<typename PlatSpec, typename T>
+constexpr ox::Error preload(Preloader<PlatSpec> *pl, ox::CommonPtrWith<T> auto *obj) noexcept {
+	OX_RETURN_ERROR(model(pl->interface(), obj));
+	return pl->pad(obj);
+}
+
+extern template class Preloader<NativePlatSpec>;
+
+}

src/preloader/include/ox/preloader/sizecatcher.hpp

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+
+#include "unionsizecatcher.hpp"
+
+namespace ox {
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t alignOf(const T &t) noexcept;
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t sizeOf(const T *t) noexcept;
+
+template<typename PlatSpec>
+class SizeCatcher: public ModelHandlerBase<SizeCatcher<PlatSpec>, OpType::Reflect> {
+	private:
+		std::size_t m_size = 0;
+
+	public:
+		constexpr explicit SizeCatcher() noexcept = default;
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion) noexcept {
+			return {};
+		}
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char*,
+				int,
+				const Vector<String>&,
+				std::size_t) noexcept {
+			return {};
+		}
+
+		template<typename T, bool force>
+		constexpr ox::Error field(const char*, UnionView<T, force>) noexcept;
+
+		template<typename T>
+		constexpr ox::Error field(const char*, const T *val) noexcept;
+
+		template<typename T>
+		constexpr ox::Error field(const char*, const T **val, std::size_t cnt) noexcept;
+
+		[[nodiscard]]
+		constexpr auto size() const noexcept {
+			return m_size;
+		}
+
+	private:
+		constexpr void pad(const auto *val) noexcept;
+};
+
+template<typename PlatSpec>
+template<typename T, bool force>
+constexpr ox::Error SizeCatcher<PlatSpec>::field(const char*, const UnionView<T, force> val) noexcept {
+	pad(val.get());
+	UnionSizeCatcher<PlatSpec> sc;
+	OX_RETURN_ERROR(model(sc.interface(), val.get()));
+	m_size += sc.size();
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error SizeCatcher<PlatSpec>::field(const char*, const T *val) noexcept {
+	pad(val);
+	m_size += sizeOf<PlatSpec>(val);
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error SizeCatcher<PlatSpec>::field(const char*, const T **val, std::size_t cnt) noexcept {
+	for (std::size_t i = 0; i < cnt; ++i) {
+		OX_RETURN_ERROR(field("", &val[i]));
+	}
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr void SizeCatcher<PlatSpec>::pad(const auto *val) noexcept {
+	const auto a = alignOf<PlatSpec>(*val);
+	const auto excess = m_size % a;
+	if (excess) {
+		m_size += a - excess;
+	}
+}
+
+template<typename PlatSpec, typename T>
+[[nodiscard]]
+constexpr std::size_t sizeOf(const T *t) noexcept {
+	if constexpr(ox::is_integral_v<T>) {
+		return sizeof(T);
+	} else if constexpr(ox::is_pointer_v<T>) {
+		return sizeof(typename PlatSpec::PtrType);
+	} else {
+		SizeCatcher<PlatSpec> sc;
+		const auto err = model(sc.interface(), t);
+		oxAssert(err, "Could not get size of type");
+		return sc.size();
+	}
+}
+
+}

src/preloader/include/ox/preloader/unionsizecatcher.hpp

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include <ox/model/modelhandleradaptor.hpp>
+#include <ox/model/optype.hpp>
+#include <ox/model/types.hpp>
+#include <ox/std/error.hpp>
+#include <ox/std/string.hpp>
+#include <ox/std/types.hpp>
+
+namespace ox {
+
+template<typename PlatSpec>
+class UnionSizeCatcher: public ModelHandlerBase<UnionSizeCatcher<PlatSpec>, OpType::Reflect> {
+	private:
+		std::size_t m_size = 0;
+
+	public:
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char* = T::TypeName,
+				int = T::TypeVersion) noexcept {
+			return {};
+		}
+
+		template<typename T>
+		constexpr ox::Error setTypeInfo(
+				const char*,
+				int,
+				const Vector<String>&,
+				std::size_t) noexcept {
+			return {};
+		}
+
+		template<typename T, bool force>
+		constexpr ox::Error field(StringViewCR, const UnionView<T, force> val) noexcept {
+			UnionSizeCatcher<PlatSpec> sc;
+			OX_RETURN_ERROR(model(sc.interface(), val.get()));
+			m_size += sc.size();
+			return {};
+		}
+
+		template<typename T>
+		constexpr ox::Error field(StringViewCR, const T *val) noexcept;
+
+		template<typename T>
+		constexpr ox::Error field(StringViewCR, const T **val, std::size_t cnt) noexcept;
+
+		[[nodiscard]]
+		constexpr auto size() const noexcept {
+			return m_size;
+		}
+
+	private:
+		template<typename T, std::size_t SmallVecSize>
+		constexpr ox::Error fieldStr(StringViewCR, const ox::BasicString<SmallVecSize> *val) noexcept;
+
+		template<typename T, std::size_t SmallVecSize>
+		constexpr ox::Error fieldVector(StringViewCR, const ox::Vector<T, SmallVecSize> *val) noexcept;
+
+		constexpr void setSize(std::size_t sz) noexcept;
+};
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error UnionSizeCatcher<PlatSpec>::field(StringViewCR, const T *val) noexcept {
+	setSize(sizeOf<PlatSpec>(val));
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T>
+constexpr ox::Error UnionSizeCatcher<PlatSpec>::field(StringViewCR, const T **val, std::size_t cnt) noexcept {
+	for (std::size_t i = 0; i < cnt; ++i) {
+		OX_RETURN_ERROR(field("", &val[i]));
+	}
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T, std::size_t SmallStrSize>
+constexpr ox::Error UnionSizeCatcher<PlatSpec>::fieldStr(StringViewCR, const ox::BasicString<SmallStrSize>*) noexcept {
+	ox::VectorMemMap<PlatSpec> v;
+	setSize(sizeOf<PlatSpec>(v));
+	return {};
+}
+
+template<typename PlatSpec>
+template<typename T, std::size_t SmallVecSize>
+constexpr ox::Error UnionSizeCatcher<PlatSpec>::fieldVector(StringViewCR, const ox::Vector<T, SmallVecSize>*) noexcept {
+	ox::VectorMemMap<PlatSpec> v;
+	setSize(sizeOf<PlatSpec>(v));
+	return {};
+}
+
+template<typename PlatSpec>
+constexpr void UnionSizeCatcher<PlatSpec>::setSize(std::size_t sz) noexcept {
+	m_size = ox::max(m_size, sz);
+}
+
+}

src/preloader/src/preloader.cpp

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <ox/preloader/preloader.hpp>
+
+namespace ox {
+
+template class Preloader<NativePlatSpec>;
+
+}

src/std/CMakeLists.txt

@@ -0,0 +1,119 @@
+if(CMAKE_CXX_COMPILER_ID MATCHES ".*Clang")
+	# enable warnings
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wunsafe-buffer-usage")
+endif()
+
+
+if(OX_USE_STDLIB AND OX_ENABLE_TRACEHOOK)
+	add_library(
+		OxTraceHook SHARED
+			src/tracehook.cpp
+	)
+else()
+	add_library(
+		OxTraceHook
+			src/tracehook.cpp
+	)
+endif()
+
+target_compile_definitions(
+	OxTraceHook PUBLIC
+		$<$<BOOL:${OX_BARE_METAL}>:OX_BARE_METAL>
+		$<$<BOOL:${OX_USE_STDLIB}>:OX_USE_STDLIB>
+		$<$<BOOL:${OX_NODEBUG}>:OX_NODEBUG>
+)
+
+add_library(
+	OxStd
+		src/assert.cpp
+		src/bit.cpp
+		src/buffer.cpp
+		src/buildinfo.cpp
+		src/byteswap.cpp
+		src/concepts.cpp
+		src/fmt.cpp
+		src/heapmgr.cpp
+		src/istreamreader.cpp
+		src/math.cpp
+		src/memops.cpp
+		src/random.cpp
+		src/reader.cpp
+		src/substitutes.cpp
+		src/stacktrace.cpp
+		src/string.cpp
+		src/stringview.cpp
+		src/strops.cpp
+		src/trace.cpp
+		src/typetraits.cpp
+		src/uuid.cpp
+		src/vec.cpp
+)
+
+if(NOT MSVC)
+	target_compile_options(OxStd PRIVATE -Wsign-conversion)
+	target_compile_options(OxStd PRIVATE -Wconversion)
+	if(${OX_OS_LINUX} AND NOT CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+		target_compile_options(OxStd PUBLIC -export-dynamic)
+		#target_link_options(OxStd PUBLIC -W1,-E)
+	elseif(${OX_OS_FREEBSD})
+		target_link_libraries(
+			OxStd PUBLIC
+				execinfo
+		)
+	endif()
+endif()
+
+if(NOT OX_BARE_METAL)
+	set_property(
+		TARGET
+			OxStd
+		PROPERTY
+			POSITION_INDEPENDENT_CODE ON
+	)
+endif()
+
+target_compile_definitions(
+	OxStd PUBLIC
+		$<$<BOOL:${OX_USE_STDLIB}>:OX_USE_STDLIB>
+		$<$<BOOL:${OX_NODEBUG}>:OX_NODEBUG>
+)
+
+if(NOT WIN32)
+	target_link_libraries(
+		OxStd PUBLIC
+			$<$<CXX_COMPILER_ID:GNU>:$<$<BOOL:${OX_USE_STDLIB}>:dl>>
+	)
+endif()
+target_link_libraries(
+	OxStd PUBLIC
+		$<$<CXX_COMPILER_ID:GNU>:gcc>
+		OxTraceHook
+		CityHash
+)
+
+target_include_directories(
+	OxStd PUBLIC
+		include
+)
+
+target_include_directories(
+	OxTraceHook PUBLIC
+		include
+)
+
+install(
+    DIRECTORY
+        include/ox
+    DESTINATION
+        include
+)
+
+install(
+	TARGETS OxStd OxTraceHook
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib
+)
+
+if(OX_RUN_TESTS)
+	add_subdirectory(test)
+endif()

src/std/include/ox/std/algorithm.hpp

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "def.hpp"
+#include "error.hpp"
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+template<typename It, typename T>
+constexpr ox::Result<size_t> findIdx(It begin, It end, T const&value) {
+	auto it = begin;
+	for (; it != end; ++it) {
+		if (*it == value) {
+			return it.offset();
+		}
+	}
+	return ox::Error{1, "item not found"};
+}
+
+template<typename It, typename T>
+constexpr It find(It begin, It end, T const&value) {
+	for (; begin != end; ++begin) {
+		if (*begin == value) {
+			return begin;
+		}
+	}
+	return end;
+}
+
+template<typename It>
+constexpr It find_if(It begin, It end, auto predicate) {
+	for (; begin != end; ++begin) {
+		if (predicate(*begin)) {
+			return begin;
+		}
+	}
+	return end;
+}
+
+template<typename It, typename Size, typename OutIt>
+constexpr OutIt copy_n(It in, Size cnt, OutIt out) {
+	for (Size i = 0; i < cnt; ++i) {
+		*out = *in;
+		++out;
+		++in;
+	}
+	return out;
+}
+
+}
+
+OX_CLANG_NOWARN_END

src/std/include/ox/std/anyptr.hpp

@@ -0,0 +1,202 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "assert.hpp"
+#include "array.hpp"
+#include "def.hpp"
+#include "span.hpp"
+
+namespace ox {
+
+namespace detail {
+
+template<bool unique>
+class AnyPtrT {
+	private:
+		struct WrapBase {
+			virtual constexpr ~WrapBase() = default;
+			virtual constexpr WrapBase *copyTo(Span<char> s) const noexcept = 0;
+			virtual constexpr operator bool() const noexcept = 0;
+			virtual void free() noexcept = 0;
+		};
+
+		template<typename T>
+		struct Wrap final: WrapBase {
+			T *data{};
+			explicit constexpr Wrap(T *pData) noexcept: data(pData) {
+			}
+			constexpr WrapBase *copyTo(Span<char> s) const noexcept override {
+				oxAssert(s.size() >= sizeof(Wrap), "too small buffer");
+				if (std::is_constant_evaluated()) {
+					return new Wrap(data);
+				} else {
+					return new(s.data()) Wrap(data);
+				}
+			}
+			constexpr operator bool() const noexcept override {
+				return data != nullptr;
+			}
+			constexpr void free() noexcept override {
+				safeDelete(data);
+				data = {};
+			}
+		};
+
+		union {
+			WrapBase *m_wrapPtr{};
+			AllocAlias<Wrap<void*>> m_wrapData;
+		} m_data;
+
+	public:
+		constexpr AnyPtrT() noexcept = default;
+
+		template<typename T>
+		constexpr AnyPtrT(T *ptr) noexcept {
+			if (std::is_constant_evaluated()) {
+				setWrapPtr(new Wrap<T>(ptr));
+			} else {
+				new(m_data.m_wrapData.data()) Wrap<T>(ptr);
+			}
+		}
+
+		constexpr AnyPtrT(AnyPtrT const &other) noexcept requires(!unique) {
+			if (other) {
+				setWrapPtr(other.getWrapPtr()->copyTo(m_data.m_wrapData.buff));
+			}
+		}
+
+		constexpr AnyPtrT(AnyPtrT &&other) noexcept {
+			if (other) {
+				setWrapPtr(other.getWrapPtr()->copyTo(m_data.m_wrapData.buff));
+				if (std::is_constant_evaluated()) {
+					ox::safeDelete(m_data.m_wrapPtr);
+				}
+				m_data.m_wrapData = {};
+			}
+		}
+
+		constexpr ~AnyPtrT() noexcept {
+			if constexpr(unique) {
+				free();
+			}
+			if (std::is_constant_evaluated()) {
+				ox::safeDelete(m_data.m_wrapPtr);
+			}
+		}
+
+		template<typename T>
+		constexpr AnyPtrT &operator=(T *ptr) noexcept {
+			if constexpr(unique) {
+				free();
+			} else if (std::is_constant_evaluated()) {
+				ox::safeDelete(m_data.m_wrapPtr);
+			}
+			if (std::is_constant_evaluated()) {
+				setWrapPtr(new Wrap(ptr));
+			} else {
+				new(m_data.m_wrapData.data()) Wrap(ptr);
+			}
+			return *this;
+		}
+
+		constexpr AnyPtrT &operator=(AnyPtrT const &ptr) noexcept requires(!unique) {
+			if (this != &ptr) {
+				if (std::is_constant_evaluated()) {
+					ox::safeDelete(m_data.m_wrapPtr);
+				}
+				if (std::is_constant_evaluated()) {
+					if (ptr) {
+						ptr.getWrapPtr()->copyTo(m_data.m_wrapData.buff);
+					}
+				} else {
+					if (ptr) {
+						setWrapPtr(ptr.getWrapPtr()->copyTo(m_data.m_wrapData.buff));
+					} else {
+						setWrapPtr(nullptr);
+					}
+				}
+			}
+			return *this;
+		}
+
+		constexpr AnyPtrT &operator=(AnyPtrT &&ptr) noexcept {
+			if (this != &ptr) {
+				if constexpr(unique) {
+					free();
+				} else if (std::is_constant_evaluated()) {
+					ox::safeDelete(m_data.m_wrapPtr);
+				}
+				if (ptr) {
+					setWrapPtr(ptr.getWrapPtr()->copyTo(m_data.m_wrapData.buff));
+					if (std::is_constant_evaluated()) {
+						ox::safeDelete(ptr.m_data.m_wrapPtr);
+						setWrapPtr(nullptr);
+					}
+				} else {
+					m_data = {};
+				}
+			}
+			return *this;
+		}
+
+		constexpr operator bool() const noexcept {
+			return getWrapPtr() && *getWrapPtr();
+		}
+
+		constexpr void free() noexcept {
+			if (auto p = getWrapPtr()) {
+				p->free();
+			}
+			if (std::is_constant_evaluated()) {
+				ox::safeDelete(m_data.m_wrapPtr);
+			}
+			m_data.m_wrapData = {};
+		}
+
+		template<typename T>
+		[[nodiscard]]
+		constexpr T *get() const noexcept {
+			if constexpr(defines::HasRTTI) {
+				return dynamic_cast<Wrap<T> const*>(getWrapPtr())->data;
+			}
+			return static_cast<Wrap<T> const*>(getWrapPtr())->data;
+		}
+
+	private:
+		constexpr void setWrapPtr(WrapBase *ptr) noexcept {
+			if (std::is_constant_evaluated()) {
+				m_data.m_wrapPtr = ptr;
+			}
+		}
+
+		constexpr WrapBase *getWrapPtr() noexcept {
+			if (std::is_constant_evaluated()) {
+				return m_data.m_wrapPtr;
+			} else {
+				return std::launder(reinterpret_cast<WrapBase*>(m_data.m_wrapData.data()));
+			}
+		}
+
+		constexpr WrapBase const *getWrapPtr() const noexcept {
+			if (std::is_constant_evaluated()) {
+				return m_data.m_wrapPtr;
+			} else {
+				return std::launder(reinterpret_cast<WrapBase const*>(m_data.m_wrapData.data()));
+			}
+		}
+
+};
+
+}
+
+using AnyPtr = detail::AnyPtrT<false>;
+using UAnyPtr = detail::AnyPtrT<true>;
+
+}

src/std/include/ox/std/array.hpp

@@ -0,0 +1,211 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "bit.hpp"
+#include "def.hpp"
+#include "error.hpp"
+#include "initializerlist.hpp"
+#include "iterator.hpp"
+#include "math.hpp"
+#include "new.hpp"
+#include "types.hpp"
+#include "utility.hpp"
+
+OX_CLANG_NOWARN_BEGIN(-Wunsafe-buffer-usage)
+
+namespace ox {
+
+template<typename T, std::size_t ArraySize>
+class Array {
+
+	public:
+		using value_type = T;
+		using size_type = std::size_t;
+
+		template<typename RefType = T&, typename PtrType = T*, bool reverse = false>
+		using iterator = SpanIterator<T, RefType, PtrType, reverse>;
+
+	private:
+		T m_items[ArraySize]{};
+
+	public:
+		constexpr Array() noexcept = default;
+
+		template<typename ...Args>
+		constexpr Array(Args ...list) noexcept: m_items{std::move(list)...} {
+		}
+
+		constexpr Array(std::initializer_list<T> list) noexcept;
+
+		constexpr Array(const Array &other);
+
+		constexpr Array(Array &&other) noexcept;
+
+		constexpr ~Array() = default;
+
+		constexpr iterator<> begin() noexcept {
+			return iterator<>(&m_items[0], 0, ArraySize);
+		}
+
+		constexpr iterator<> end() noexcept {
+			return iterator<>(&m_items[0], ArraySize, ArraySize);
+		}
+
+		constexpr iterator<const T&, const T*> begin() const noexcept {
+			return iterator<const T&, const T*>(&m_items[0], 0, ArraySize);
+		}
+
+		constexpr iterator<const T&, const T*> end() const noexcept {
+			return iterator<const T&, const T*>(&m_items[0], ArraySize, ArraySize);
+		}
+
+		constexpr iterator<T&, T*, true> rbegin() noexcept {
+			return iterator<T&, T*, true>(&m_items[0], ArraySize - 1, ArraySize);
+		}
+
+		constexpr iterator<T&, T*, true> rend() noexcept {
+			return iterator<T&, T*, true>(&m_items[0], MaxValue<size_type>, ArraySize);
+		}
+
+		constexpr iterator<const T&, const T*, true> rbegin() const noexcept {
+			return iterator<const T&, const T*, true>(m_items, ArraySize - 1, ArraySize);
+		}
+
+		constexpr iterator<const T&, const T*, true> rend() const noexcept {
+			return iterator<const T&, const T*, true>(m_items, MaxValue<size_type>, ArraySize);
+		}
+
+		constexpr bool operator==(const Array &other) const;
+
+		constexpr Array &operator=(const Array &other);
+
+		constexpr Array &operator=(Array &&other) noexcept;
+
+		[[nodiscard]]
+		constexpr T &operator[](std::size_t i) noexcept;
+
+		[[nodiscard]]
+		constexpr const T &operator[](std::size_t i) const noexcept;
+
+		[[nodiscard]]
+		constexpr std::size_t size() const noexcept;
+
+		[[nodiscard]]
+		constexpr T *data() noexcept {
+			return m_items;
+		}
+
+		[[nodiscard]]
+		constexpr const T *data() const noexcept {
+			return m_items;
+		}
+
+		[[nodiscard]]
+		constexpr bool contains(const T&) const;
+
+};
+
+template<typename T, std::size_t ArraySize, typename RefType, bool reverse>
+using ArrayIt = typename Array<T, ArraySize>::template iterator<RefType, reverse>;
+
+template<typename T, std::size_t ArraySize, typename RefType, bool reverse>
+constexpr ArrayIt<T, ArraySize, RefType, reverse> operator+(std::size_t n, const ArrayIt<T, ArraySize, RefType, reverse> &a) {
+	return a + n;
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr Array<T, ArraySize>::Array(std::initializer_list<T> list) noexcept {
+	for (auto i = 0ul; auto &item : list) {
+		this->operator[](i) = item;
+		++i;
+	}
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr Array<T, ArraySize>::Array(const Array &other) {
+	for (std::size_t i = 0; i < ArraySize; ++i) {
+		m_items[i] = T(other.m_items[i]);
+	}
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr Array<T, ArraySize>::Array(Array &&other) noexcept {
+	if (this != &other) {
+		for (std::size_t i = 0; i < ArraySize; ++i) {
+			m_items[i] = T(std::move(other.m_items[i]));
+		}
+	}
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr bool Array<T, ArraySize>::operator==(const Array &other) const {
+	if (std::is_constant_evaluated()) {
+		for (std::size_t i = 0; i < ArraySize; i++) {
+			if (!(m_items[i] == other.m_items[i])) {
+				return false;
+			}
+		}
+		return true;
+	} else {
+		return memcmp(this, &other, sizeof(*this)) == 0;
+	}
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr Array<T, ArraySize> &Array<T, ArraySize>::operator=(const Array &other) {
+	if (this != &other) {
+		for (std::size_t i = 0; i < ArraySize; ++i) {
+			m_items[i] = other.m_items[i];
+		}
+	}
+	return *this;
+	return *this;
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr Array<T, ArraySize> &Array<T, ArraySize>::operator=(Array &&other) noexcept {
+	if (this != &other) {
+		for (std::size_t i = 0; i < ArraySize; ++i) {
+			m_items[i] = std::move(other.m_items[i]);
+		}
+	}
+	return *this;
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr T &Array<T, ArraySize>::operator[](std::size_t i) noexcept {
+	boundsCheck(i, size(), "Array access overflow");
+	return m_items[i];
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr const T &Array<T, ArraySize>::operator[](std::size_t i) const noexcept {
+	boundsCheck(i, size(), "Array access overflow");
+	return m_items[i];
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr std::size_t Array<T, ArraySize>::size() const noexcept {
+	return ArraySize;
+}
+
+template<typename T, std::size_t ArraySize>
+constexpr bool Array<T, ArraySize>::contains(const T &v) const {
+	for (std::size_t i = 0; i < ArraySize; i++) {
+		if (m_items[i] == v) {
+			return true;
+		}
+	}
+	return false;
+}
+
+}
+
+OX_CLANG_NOWARN_END

src/std/include/ox/std/assert.hpp

@@ -0,0 +1,118 @@
+/*
+ * Copyright 2015 - 2025 gary@drinkingtea.net
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "def.hpp"
+#include "defines.hpp"
+#include "error.hpp"
+#include "realstd.hpp"
+#include "stacktrace.hpp"
+#include "trace.hpp"
+#include "typetraits.hpp"
+
+namespace ox {
+
+[[noreturn]]
+void panic(
+	Error const&err,
+	StringViewCR panicMsg,
+	std::source_location const &src = std::source_location::current()) noexcept;
+
+[[noreturn]]
+inline void panic(
+	StringViewCR panicMsg,
+	std::source_location const &src = std::source_location::current()) noexcept {
+	panic(Error{1}, panicMsg, src);
+}
+
+[[noreturn]]
+constexpr void constexprPanic(
+	StringViewCR panicMsg,
+	Error const &err = {},
+	std::source_location const &src = std::source_location::current()) noexcept {
+	if (!std::is_constant_evaluated()) {
+		panic(err, panicMsg, src);
+	} else {
+		while (true);
+	}
+}
+
+void assertFailFuncRuntime(
+	StringViewCR assertTxt,
+	StringViewCR msg,
+	std::source_location const &src = std::source_location::current()) noexcept;
+
+void assertFailFuncRuntime(
+	Error const &err,
+	StringViewCR,
+	StringViewCR assertMsg,
+	std::source_location const &src = std::source_location::current()) noexcept;
+
+constexpr void assertFunc(
+	bool const pass,
+	[[maybe_unused]]StringViewCR assertTxt,
+	[[maybe_unused]]StringViewCR msg,
+	std::source_location const &src = std::source_location::current()) noexcept {
+	if (!pass) {
+		if (!std::is_constant_evaluated()) {
+			assertFailFuncRuntime(assertTxt, msg, src);
+		} else {
+			while (true);
+		}
+	}
+}
+
+constexpr void assertFunc(
+	Error const &err,
+	StringViewCR,
+	StringViewCR assertMsg,
+	std::source_location const &src = std::source_location::current()) noexcept {
+	if (err) {
+		if (!std::is_constant_evaluated()) {
+			assertFailFuncRuntime(err, {}, assertMsg, src);
+		} else {
+			while (true);
+		}
+	}
+}
+
+constexpr void expect(
+	auto const &actual,
+	auto const &expected,
+	std::source_location const &src = std::source_location::current()) noexcept {
+	if (actual != expected) {
+		 if (!std::is_constant_evaluated()) {
+#if defined(OX_USE_STDLIB)
+			oxErrf(
+				"\n\033[31;1;1mASSERT FAILURE:\033[0m [{}:{}]: {}\n",
+				src.file_name(),
+				src.line(),
+				"Value incorrect");
+			oxErrf(
+				"expected: {}\nactual:   {}\n",
+				detail::toStringView<true>(expected),
+				detail::toStringView<true>(actual));
+			printStackTrace(2);
+			oxTracef(
+				"assert.expect", "Failed assert: {} == {} [{}:{}]",
+				detail::toStringView<true>(actual),
+				detail::toStringView<true>(expected),
+				src.file_name(),
+				src.line());
+			std::abort();
+#else
+			constexprPanic("Comparison failed", {}, src);
+#endif
+		} else {
+			while (true);
+		}
+	}
+}
+
+}