diff --git a/.vimspector.json b/.vimspector.json
new file mode 100644
index 0000000..4265e7a
--- /dev/null
+++ b/.vimspector.json
@@ -0,0 +1,28 @@
+{
+	"configurations": {
+		"run_ctest_native": {
+			"default": true,
+			"adapter": "CodeLLDB",
+			"configuration": {
+				"request": "launch",
+				"stopOnEntry": true,
+				"console": "integratedTerminal",
+				"program": "ctest",
+				"cwd": "${workspaceRoot}/build"
+			}
+		},
+		"run_native": {
+			"adapter": "CodeLLDB",
+			"variables": {
+				"Executable": "s6zer_test"
+			},
+			"configuration": {
+				"request": "launch",
+				"stopOnEntry": true,
+				"console": "integratedTerminal",
+				"program": "${workspaceRoot}/build/bin/${Executable}",
+				"cwd": "${workspaceRoot}/build"
+			}
+		}
+	}
+}
diff --git a/framework/CMakeLists.txt b/framework/CMakeLists.txt
index 822919f..ecb3725 100644
--- a/framework/CMakeLists.txt
+++ b/framework/CMakeLists.txt
@@ -5,6 +5,7 @@ project(framework)
 add_subdirectory(engine)
 add_subdirectory(logger)
 add_subdirectory(resource_manager)
+add_subdirectory(s6zer)
 add_subdirectory(common_components)
 add_subdirectory(std_utils)
 add_subdirectory(random)
diff --git a/framework/s6zer/CMakeLists.txt b/framework/s6zer/CMakeLists.txt
new file mode 100644
index 0000000..7e195e7
--- /dev/null
+++ b/framework/s6zer/CMakeLists.txt
@@ -0,0 +1,23 @@
+cmake_minimum_required(VERSION 3.9 FATAL_ERROR)
+
+project(s6zer CXX)
+
+add_library(s6zer INTERFACE
+	#./src/s6zer/stream.hpp
+	#./src/s6zer/serialize.hpp
+)
+
+add_library(MM::s6zer ALIAS s6zer)
+
+target_include_directories(s6zer INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/src")
+
+target_compile_features(s6zer INTERFACE cxx_std_17)
+
+#target_link_libraries(s6zer
+	#INTERFACE
+#)
+
+if (BUILD_TESTING)
+	add_subdirectory(test)
+endif()
+
diff --git a/framework/s6zer/src/mm/s6zer/serialize.hpp b/framework/s6zer/src/mm/s6zer/serialize.hpp
new file mode 100644
index 0000000..71b27d4
--- /dev/null
+++ b/framework/s6zer/src/mm/s6zer/serialize.hpp
@@ -0,0 +1,33 @@
+#pragma once
+
+#include "./stream.hpp"
+
+namespace MM::s6zer {
+
+// serialize macros
+
+// TODO: make use of ADL, like nlohmann::json does.
+
+/*
+	defines mm_serialize functions for you.
+	a "stream" object is in scope (StreamWriter/StreamReader),
+	as well as the object of Type called "data".
+eg:
+MM_DEFINE_SERIALIZE(Test1,
+	MM_S6ZER_BAIL(stream.serializeBits(data.seq, 16))
+	MM_S6ZER_BAIL(stream.serializeBits(data.data1, 8))
+)
+*/
+// TODO: refine, so we dont have to do MM_S6ZER_BAIL() everytime
+#define MM_DEFINE_SERIALIZE(Type, ...) \
+inline bool mm_serialize(MM::s6zer::StreamWriter& stream, const Type& data) { \
+	__VA_ARGS__ \
+	return true; \
+} \
+inline bool mm_serialize(MM::s6zer::StreamReader& stream, Type& data) { \
+	__VA_ARGS__ \
+	return true; \
+}
+
+} // MM::s6zer
+
diff --git a/framework/s6zer/src/mm/s6zer/stream.hpp b/framework/s6zer/src/mm/s6zer/stream.hpp
new file mode 100644
index 0000000..e110c9a
--- /dev/null
+++ b/framework/s6zer/src/mm/s6zer/stream.hpp
@@ -0,0 +1,331 @@
+#pragma once
+
+#include <cstddef> // size_t
+#include <cstdint> // uint8_t, etc
+
+#include <type_traits>
+
+#include <cassert>
+
+// TODO: make asserts redefinable
+
+namespace MM::s6zer {
+
+// this is heavily inspired by Glenn Fiedler's (Gaffer On Games) serializers
+// https://www.gafferongames.com/post/reading_and_writing_packets/
+// https://www.gafferongames.com/post/serialization_strategies/
+
+// internal helpers
+namespace detail {
+	// TODO: ugly, replace when c++20
+	[[nodiscard]] constexpr size_t first_bit_set8(const uint8_t number) {
+		return
+			(number & 0b10000000) ? 8 :
+			(number & 0b01000000) ? 7 :
+			(number & 0b00100000) ? 6 :
+			(number & 0b00010000) ? 5 :
+			(number & 0b00001000) ? 4 :
+			(number & 0b00000100) ? 3 :
+			(number & 0b00000010) ? 2 :
+			(number & 0b00000001) ? 1 :
+			0
+		;
+	}
+
+	[[nodiscard]] constexpr size_t first_bit_set32(const uint32_t number) {
+		return
+			(number & 0xff000000) ? first_bit_set8((number >> 24) & 0xff) + 24 :
+			(number & 0x00ff0000) ? first_bit_set8((number >> 16) & 0xff) + 16 :
+			(number & 0x0000ff00) ? first_bit_set8((number >> 8) & 0xff) + 8 :
+			(number & 0x000000ff) ? first_bit_set8(number & 0xff) :
+			0
+		;
+	}
+
+	[[nodiscard]] constexpr uint32_t byte_swap(const uint32_t value) noexcept {
+		return
+			((value & 0xff000000) >> 24) |
+			((value & 0x00ff0000) >> 8) |
+			((value & 0x0000ff00) << 8) |
+			((value & 0x000000ff) << 24)
+		;
+	}
+
+	[[nodiscard]] constexpr uint16_t byte_swap(const uint16_t value) noexcept {
+		return
+			((value & 0xff00) >> 8) |
+			((value & 0x00ff) << 8)
+		;
+	}
+
+	[[nodiscard]] constexpr uint8_t byte_swap(const uint8_t value) noexcept {
+		// noop
+		return value;
+	}
+
+	template<typename T>
+	[[nodiscard]] constexpr const T& max(const T& a, const T& b) noexcept {
+		return (a < b) ? b : a;
+	}
+
+} // detail
+
+// TODO: maybe 64bit?
+// TODO: is this detail?
+[[nodiscard]] constexpr size_t bits_required(const uint32_t numbers) {
+	return detail::first_bit_set32(numbers);
+}
+
+[[nodiscard]] constexpr uint32_t serialize_byte_order(const uint32_t value) {
+	// TODO: only works on little endian for now
+	if constexpr (true) { // native is little endian
+		return value;
+	} else { // native is big endian
+		return detail::byte_swap(value);
+	}
+}
+
+// helper for fake exceptions
+#ifndef MM_S6ZER_BAIL
+#define MM_S6ZER_BAIL(...) { \
+	if (! __VA_ARGS__) { \
+		return false; \
+	} \
+}
+#endif
+
+struct StreamWriter {
+	StreamWriter(void) = delete;
+	StreamWriter(uint32_t* data, size_t size) : _data(data), _data_size(size) {
+		assert(size != 0);
+		assert(size % sizeof(uint32_t) == 0);
+		assert(data != nullptr);
+	}
+
+	// do i still need them?
+	[[nodiscard]] static constexpr bool isWriting(void) noexcept { return true; }
+	[[nodiscard]] static constexpr bool isReading(void) noexcept { return false; }
+
+	[[nodiscard]] bool flush(void) noexcept {
+		if (_scratch_bits != 0) {
+			// check if space in buffer
+			if (_data_size < (_word_index + 1) * sizeof(uint32_t)) {
+				return false;
+			}
+
+			_data[_word_index] = serialize_byte_order(static_cast<uint32_t>(_scratch & 0xffffffff));
+			_scratch >>= 32; // new bits are allways unset, so we can just allways 32
+			// we dont like negative
+			_scratch_bits = detail::max(static_cast<int32_t>(_scratch_bits) - 32, 0);
+			_word_index++;
+		}
+
+		return true;
+	}
+
+	template<typename T>
+	[[nodiscard]] bool serializeBits(const T value, const size_t number_of_bits = sizeof(T)*8) noexcept {
+		static_assert(std::is_integral_v<T>, "type needs to be an integer");
+		static_assert(std::is_unsigned_v<T>, "type needs to be unsigned");
+		static_assert(sizeof(T) <= 4, "not yet defined for > 32bit");
+		assert(number_of_bits <= sizeof(T)*8);
+		assert(number_of_bits > 0);
+
+		// do scratching
+		_scratch |= static_cast<uint64_t>(value) << _scratch_bits;
+		_scratch_bits += number_of_bits;
+		_bits_written += number_of_bits;
+
+		if (_scratch_bits >= 32) {
+			return flush();
+		}
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeBool(const bool value) noexcept {
+		return serializeBits(static_cast<uint32_t>(value), 1);
+	}
+
+	template<typename T>
+	[[nodiscard]] bool serializeInt(const T value, const T min, const T max) noexcept {
+		static_assert(std::is_integral_v<T>, "type needs to be an integer");
+		static_assert(sizeof(T) <= 4, "not yet defined for > 32bit");
+		assert(max >= min);
+		assert(value >= min);
+		assert(value <= max);
+
+		const size_t bits = bits_required(max - min);
+
+		return serializeBits(static_cast<uint32_t>(value - min), bits);
+	}
+
+	[[nodiscard]] bool serializeFloat(const float value) noexcept {
+		// TODO: dont use loop
+		for (size_t i = 0; i < sizeof(float); i++) {
+			MM_S6ZER_BAIL(serializeBits(reinterpret_cast<const uint8_t*>(&value)[i], 8));
+		}
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeDouble(const double value) noexcept {
+		// TODO: dont use loop
+		for (size_t i = 0; i < sizeof(double); i++) {
+			MM_S6ZER_BAIL(serializeBits(reinterpret_cast<const uint8_t*>(&value)[i], 8));
+		}
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeFloatCompressed(const float value, const float min, const float max, const float resolution) noexcept {
+		assert(max >= min);
+		assert(value >= min);
+		assert(value <= max);
+
+		// TODO: handle those rounding errors
+
+		const float numbers = (max - min) / resolution;
+		const size_t bits = bits_required(static_cast<uint32_t>(numbers));
+
+		const uint32_t tmp_value = static_cast<uint32_t>((value - min) / resolution);
+
+		return serializeBits(tmp_value, bits);
+	}
+
+	[[nodiscard]] size_t bytesWritten(void) noexcept {
+		// TODO: is this assert valid?
+		assert(_scratch_bits == 0);
+
+		//return _bits_written/8 + ((_bits_written % 8) ? 1 : 0);
+		return (_bits_written+7) / 8;
+	}
+
+	uint32_t* _data {nullptr};
+	size_t _data_size {0};
+
+	uint64_t _scratch {0};
+	size_t _scratch_bits {0};
+	size_t _word_index {0};
+	size_t _bits_written {0}; // includes bits still in scratch
+};
+
+struct StreamReader {
+	StreamReader(void) = delete;
+	// !! StreamReader assumes the data buffer has whole uint32_t,
+	// so at the end, even though data_size might be less then 4 bytes,
+	// here is actually a full, empty uint32
+	// !! enable AddressSanitzier during development and testing
+	StreamReader(const uint32_t* data, size_t size) : _data(data), _data_size(size) {
+		assert(size != 0);
+		//assert(size % sizeof(uint32_t) == 0);
+		assert(data != nullptr);
+	}
+
+	// do i still need them?
+	[[nodiscard]] static constexpr bool isWriting(void) noexcept { return false; }
+	[[nodiscard]] static constexpr bool isReading(void) noexcept { return true; }
+
+	template<typename T>
+	[[nodiscard]] bool serializeBits(T& value, const size_t number_of_bits = sizeof(T)*8) noexcept {
+		static_assert(std::is_integral_v<T>, "type needs to be an integer");
+		static_assert(std::is_unsigned_v<T>, "type needs to be unsigned");
+		static_assert(sizeof(T) <= 4, "not yet defined for > 32bit");
+		assert(number_of_bits <= sizeof(T)*8);
+		assert(number_of_bits > 0);
+
+		if (_scratch_bits < number_of_bits) {
+			if (_bits_read + number_of_bits > _data_size*8) {
+				// would read past end
+				return false;
+			}
+
+			_scratch |= static_cast<uint64_t>(serialize_byte_order(_data[_word_index])) << _scratch_bits;
+			_word_index++;
+			_scratch_bits += 32;
+		}
+
+		value = _scratch & ((uint64_t(1) << number_of_bits) - 1);
+
+		_scratch >>= number_of_bits;
+		_scratch_bits -= number_of_bits;
+		_bits_read += number_of_bits;
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeBool(bool& value) noexcept {
+		uint32_t tmp_value {0};
+		MM_S6ZER_BAIL(serializeBits(tmp_value, 1));
+
+		// :)
+		value = tmp_value != 0;
+
+		return true;
+	}
+
+	template<typename T>
+	[[nodiscard]] bool serializeInt(T& value, const T min, const T max) noexcept {
+		static_assert(std::is_integral_v<T>, "type needs to be an integer");
+		static_assert(sizeof(T) <= 4, "not yet defined for > 32bit");
+		assert(max >= min);
+
+		const size_t bits = bits_required(max - min);
+
+		uint32_t tmp_val {0};
+		MM_S6ZER_BAIL(serializeBits(tmp_val, bits));
+
+		value = static_cast<T>(tmp_val) + min;
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeFloat(float& value) noexcept {
+		// TODO: dont use loop
+		for (size_t i = 0; i < sizeof(float); i++) {
+			MM_S6ZER_BAIL(serializeBits(reinterpret_cast<uint8_t*>(&value)[i], 8));
+		}
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeDouble(double& value) noexcept {
+		// TODO: dont use loop
+		for (size_t i = 0; i < sizeof(double); i++) {
+			MM_S6ZER_BAIL(serializeBits(reinterpret_cast<uint8_t*>(&value)[i], 8));
+		}
+
+		return true;
+	}
+
+	[[nodiscard]] bool serializeFloatCompressed(float& value, const float min, const float max, const float resolution) noexcept {
+		assert(max >= min);
+
+		// TODO: use rounding, rn it snaps (floor)
+
+		const float numbers = (max - min) / resolution;
+		const size_t bits = bits_required(static_cast<uint32_t>(numbers));
+
+		uint32_t tmp_value {0};
+		MM_S6ZER_BAIL(serializeBits(tmp_value, bits));
+
+		value = static_cast<float>(tmp_value) * resolution + min;
+
+		return true;
+	}
+
+	[[nodiscard]] size_t bytesRead(void) noexcept {
+		return (_bits_read+7) / 8;
+	}
+
+	const uint32_t* _data {nullptr};
+	size_t _data_size {0};
+
+	uint64_t _scratch {0};
+	size_t _scratch_bits {0};
+	size_t _word_index {0};
+	size_t _bits_read {0};
+};
+
+} // MM::s6zer
+
diff --git a/framework/s6zer/test/CMakeLists.txt b/framework/s6zer/test/CMakeLists.txt
new file mode 100644
index 0000000..120b3a7
--- /dev/null
+++ b/framework/s6zer/test/CMakeLists.txt
@@ -0,0 +1,18 @@
+add_executable(s6zer_test
+	test.cpp
+)
+
+target_include_directories(s6zer_test PRIVATE ".")
+
+target_compile_features(s6zer_test PRIVATE cxx_std_17)
+
+target_link_libraries(s6zer_test
+	gtest_main
+
+	s6zer
+
+	random
+)
+
+add_test(NAME s6zer_test COMMAND s6zer_test)
+
diff --git a/framework/s6zer/test/test.cpp b/framework/s6zer/test/test.cpp
new file mode 100644
index 0000000..bcac55c
--- /dev/null
+++ b/framework/s6zer/test/test.cpp
@@ -0,0 +1,553 @@
+#include <mm/s6zer/serialize.hpp>
+
+#include <array>
+#include <ostream>
+
+#include <mm/random/srng.hpp>
+#include <mm/scalar_range2.hpp>
+
+#include <gtest/gtest.h>
+
+namespace MM {
+	template<typename Char, typename T>
+	std::basic_ostream<Char>& operator<<(std::basic_ostream<Char>& out, const MM::ScalarRange2<T>& range) {
+		return out << "{ min: " << static_cast<int64_t>(range.min()) << ", max: " << static_cast<int64_t>(range.max()) << " }";
+	}
+} // MM
+
+TEST(s6zer, bits_required_static) {
+	static_assert(MM::s6zer::bits_required(0)== 0);
+	static_assert(MM::s6zer::bits_required(1)== 1);
+	static_assert(MM::s6zer::bits_required(2)== 2);
+	static_assert(MM::s6zer::bits_required(3)== 2);
+	static_assert(MM::s6zer::bits_required(4)== 3);
+	static_assert(MM::s6zer::bits_required(32)== 6);
+	static_assert(MM::s6zer::bits_required(0xffffffff)== 32);
+	static_assert(MM::s6zer::bits_required(0xffffff00)== 32);
+	static_assert(MM::s6zer::bits_required(0xf0000a00)== 32);
+	static_assert(MM::s6zer::bits_required(0x0f000000)== 28);
+	static_assert(MM::s6zer::bits_required(0x0000f000)== 16);
+}
+
+TEST(s6zer, byte_swap) {
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint8_t>(0x00)) == 0x00);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint8_t>(0xff)) == 0xff);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint8_t>(0x10)) == 0x10);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint8_t>(0xfe)) == 0xfe);
+
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint16_t>(0x0000)) == 0x0000);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint16_t>(0xffff)) == 0xffff);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint16_t>(0x00fe)) == 0xfe00);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint16_t>(0xfefe)) == 0xfefe);
+
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint32_t>(0x00000000)) == 0x00000000);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint32_t>(0xffffffff)) == 0xffffffff);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint32_t>(0xf0f00000)) == 0x0000f0f0);
+	static_assert(MM::s6zer::detail::byte_swap(static_cast<uint32_t>(0xfe0000ef)) == 0xef0000fe);
+}
+
+TEST(s6zer, stream_normalcase1) {
+	const uint32_t num1_orig {0b111};
+	const uint32_t num1_orig_bits {3};
+	const uint32_t num2_orig {0b1111111111};
+	const uint32_t num2_orig_bits {10};
+	const uint32_t num3_orig {0b111111111111111111111111};
+	const uint32_t num3_orig_bits {24};
+
+	std::array<uint32_t, 2> buffer;
+	size_t buffer_size = buffer.size()*sizeof(uint32_t);
+	{
+		MM::s6zer::StreamWriter writer{buffer.data(), buffer_size};
+
+		bool r = false;
+		ASSERT_EQ(writer._scratch, 0x0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, 0);
+		ASSERT_EQ(writer.bytesWritten(), 0);
+
+		r = writer.serializeBits(num1_orig, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b0000000000000000000000000000000000000000000000000000000000000'111);
+		ASSERT_EQ(writer._scratch_bits, 3);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits);
+
+		r = writer.serializeBits(num2_orig, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b000000000000000000000000000000000000000000000000000'111'1111111111);
+		ASSERT_EQ(writer._scratch_bits, 3+10);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits);
+
+		r = writer.serializeBits(num3_orig, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b00000000000000000000000000000000000000000000000000000000000'11111);
+		ASSERT_EQ(writer._scratch_bits, (3+10+24)-32);
+		ASSERT_EQ(writer._word_index, 1);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits);
+
+		r = writer.flush();
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._word_index, 2);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits); // flush does not change bits written
+		ASSERT_EQ(writer.bytesWritten(), 5); // 4.625 , so ceil
+
+		buffer_size = writer.bytesWritten();
+	}
+
+	std::cout << "buffer_size: " << buffer_size << "\n";
+
+	ASSERT_EQ(buffer[0], 0xffffffff);
+	ASSERT_EQ(buffer[1], 0b000000000000000000000000000'11111);
+
+	{
+		MM::s6zer::StreamReader reader{buffer.data(), buffer_size};
+
+		bool r = false;
+		ASSERT_EQ(reader._scratch, 0x0);
+		ASSERT_EQ(reader._scratch_bits, 0);
+		ASSERT_EQ(reader._word_index, 0);
+
+		uint32_t num1 {0};
+		r = reader.serializeBits(num1, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num1, num1_orig);
+		ASSERT_EQ(reader._scratch, 0b00000000'00000000'00000000'00000000'000'11111111111111111111111111111);
+		ASSERT_EQ(reader._scratch_bits, 29);
+		ASSERT_EQ(reader._word_index, 1); // index refers to next dword
+
+		uint32_t num2 {0};
+		r = reader.serializeBits(num2, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num2, num2_orig);
+		ASSERT_EQ(reader._scratch, 0b00000000'00000000'00000000'00000000'000'00000'00000'1111111111111111111);
+		ASSERT_EQ(reader._scratch_bits, 19);
+		ASSERT_EQ(reader._word_index, 1); // <=32, so should not yet have read next dword
+
+		uint32_t num3 {0};
+		r = reader.serializeBits(num3, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num3, num3_orig);
+		ASSERT_EQ(reader._scratch, 0x0); // no data left
+		ASSERT_EQ(reader._scratch_bits, 27);
+		ASSERT_EQ(reader._word_index, 2);
+
+		// error case
+		uint32_t num4 {0};
+		r = reader.serializeBits(num4, 32);
+		ASSERT_FALSE(r);
+	}
+}
+
+TEST(s6zer, stream_normalcase1_1) {
+	const uint32_t num1_orig {0b101};
+	const uint32_t num1_orig_bits {3};
+	const uint32_t num2_orig {0b1010101010};
+	const uint32_t num2_orig_bits {10};
+	const uint32_t num3_orig {0b101010101010101010101010};
+	const uint32_t num3_orig_bits {24};
+
+	std::array<uint32_t, 2> buffer;
+	size_t buffer_size = buffer.size()*sizeof(uint32_t);
+	{
+		MM::s6zer::StreamWriter writer{buffer.data(), buffer_size};
+
+		bool r = false;
+		ASSERT_EQ(writer._scratch, 0x0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, 0);
+		ASSERT_EQ(writer.bytesWritten(), 0);
+
+		r = writer.serializeBits(num1_orig, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b0000000000000000000000000000000000000000000000000000000000000'101);
+		ASSERT_EQ(writer._scratch_bits, 3);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits);
+
+		r = writer.serializeBits(num2_orig, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b000000000000000000000000000000000000000000000000000'1010101010'101);
+		ASSERT_EQ(writer._scratch_bits, 3+10);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits);
+
+		r = writer.serializeBits(num3_orig, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0b00000000000000000000000000000000000000000000000000000000000'10101); // the high bits of the 24
+		ASSERT_EQ(writer._scratch_bits, (3+10+24)-32);
+		ASSERT_EQ(writer._word_index, 1);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits);
+
+		r = writer.flush();
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._word_index, 2);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits); // flush does not change bits written
+		ASSERT_EQ(writer.bytesWritten(), 5); // 4.625 , so ceil
+
+		buffer_size = writer.bytesWritten();
+	}
+
+	std::cout << "buffer_size: " << buffer_size << "\n";
+
+	ASSERT_EQ(buffer[0], 0b0101010101010101010'1010101010'101);
+	ASSERT_EQ(buffer[1], 0b000000000000000000000000000'10101);
+
+	{
+		MM::s6zer::StreamReader reader{buffer.data(), buffer_size};
+
+		bool r = false;
+		ASSERT_EQ(reader._scratch, 0x0);
+		ASSERT_EQ(reader._scratch_bits, 0);
+		ASSERT_EQ(reader._word_index, 0);
+
+		uint32_t num1 {0};
+		r = reader.serializeBits(num1, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num1, num1_orig);
+		ASSERT_EQ(reader._scratch, 0b00000000'00000000'00000000'00000000'000'0101010101010101010'1010101010);
+		ASSERT_EQ(reader._scratch_bits, 29);
+		ASSERT_EQ(reader._word_index, 1); // index refers to next dword
+
+		uint32_t num2 {0};
+		r = reader.serializeBits(num2, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num2, num2_orig);
+		ASSERT_EQ(reader._scratch, 0b00000000'00000000'00000000'00000000'000'00000'00000'0101010101010101010);
+		ASSERT_EQ(reader._scratch_bits, 19);
+		ASSERT_EQ(reader._word_index, 1); // <=32, so should not yet have read next dword
+
+		uint32_t num3 {0};
+		r = reader.serializeBits(num3, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num3, num3_orig);
+		ASSERT_EQ(reader._scratch, 0x0); // no data left
+		ASSERT_EQ(reader._scratch_bits, 27);
+		ASSERT_EQ(reader._word_index, 2);
+
+		// error case
+		uint32_t num4 {0};
+		r = reader.serializeBits(num4, 32);
+		ASSERT_FALSE(r);
+	}
+}
+
+TEST(s6zer, stream_normalcase2) {
+	// we now take each number as its maximum, synthetic for testing
+	const uint32_t num1_orig {17};
+	const uint32_t num1_orig_bits {MM::s6zer::bits_required(num1_orig)};
+	const uint32_t num2_orig {1};
+	const uint32_t num2_orig_bits {MM::s6zer::bits_required(num2_orig)};
+	const uint32_t num3_orig {1298989};
+	const uint32_t num3_orig_bits {MM::s6zer::bits_required(num3_orig)};
+
+	std::array<uint32_t, 2> buffer;
+	size_t buffer_size = buffer.size()*sizeof(uint32_t);
+	{
+		MM::s6zer::StreamWriter writer{buffer.data(), buffer_size};
+
+		// fewer asserts
+		bool r = false;
+		ASSERT_EQ(writer._scratch, 0x0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._word_index, 0);
+		ASSERT_EQ(writer._bits_written, 0);
+		ASSERT_EQ(writer.bytesWritten(), 0);
+
+		r = writer.serializeBits(num1_orig, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits);
+
+		r = writer.serializeBits(num2_orig, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits);
+
+		r = writer.serializeBits(num3_orig, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits);
+
+		r = writer.flush();
+		ASSERT_TRUE(r);
+		ASSERT_EQ(writer._scratch, 0);
+		ASSERT_EQ(writer._scratch_bits, 0);
+		ASSERT_EQ(writer._bits_written, num1_orig_bits+num2_orig_bits+num3_orig_bits); // flush does not change bits written
+
+		buffer_size = writer.bytesWritten();
+	}
+
+	std::cout << "buffer_size: " << buffer_size << "\n";
+
+	{
+		MM::s6zer::StreamReader reader{buffer.data(), buffer_size};
+
+		bool r = false;
+		ASSERT_EQ(reader._scratch, 0x0);
+		ASSERT_EQ(reader._scratch_bits, 0);
+		ASSERT_EQ(reader._word_index, 0);
+		ASSERT_EQ(reader._bits_read, 0);
+
+		uint32_t num1 {0};
+		r = reader.serializeBits(num1, num1_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num1, num1_orig);
+
+		uint32_t num2 {0};
+		r = reader.serializeBits(num2, num2_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num2, num2_orig);
+
+		uint32_t num3 {0};
+		r = reader.serializeBits(num3, num3_orig_bits);
+		ASSERT_TRUE(r);
+		ASSERT_EQ(num3, num3_orig);
+
+		// error case
+		uint32_t num4 {0};
+		r = reader.serializeBits(num4, 32);
+		ASSERT_FALSE(r);
+	}
+}
+
+// emscripten cant do this
+#ifndef __EMSCRIPTEN__
+bool serialize_int_death_fn(void) {
+		std::array<uint32_t, 32> dummy_buffer;
+		MM::s6zer::StreamReader reader{dummy_buffer.data(), dummy_buffer.size()*sizeof(uint32_t)};
+		int32_t value{0};
+
+		MM_S6ZER_BAIL(reader.serializeInt(value, 20, -20)); // wrong order
+
+	return true;
+}
+
+TEST(s6zer, serialize_int_death) {
+	ASSERT_DEATH({
+		[[maybe_unused]] bool ret = serialize_int_death_fn();
+	}, "failed");
+}
+#endif
+
+TEST(s6zer, reader_bits_bug1) {
+	const std::array<uint32_t, 2> buffer {
+		0x27'5c'19'a1,
+		0x00'00'3a'c3
+	};
+	const size_t buffer_size {6};
+
+	MM::s6zer::StreamReader reader{buffer.data(), buffer_size};
+
+	uint8_t value_0 {0};
+	ASSERT_TRUE(reader.serializeBits(value_0));
+	ASSERT_EQ(value_0, 0xa1);
+
+	ASSERT_EQ(reader._scratch_bits, 24);
+	ASSERT_EQ(reader._scratch, 0x0000000000'27'5c'19);
+
+	uint32_t value_1 {0};
+	ASSERT_TRUE(reader.serializeBits(value_1));
+	ASSERT_EQ(value_1, 0xc3'27'5c'19);
+
+	ASSERT_EQ(reader._scratch_bits, 24);
+	ASSERT_EQ(reader._scratch, 0x00000000000000'3a);
+
+	uint8_t value_2 {0};
+	ASSERT_TRUE(reader.serializeBits(value_2));
+	ASSERT_EQ(value_2, 0x3a);
+
+	ASSERT_EQ(reader._scratch, 0x0000000000000000);
+}
+
+struct TestStruct {
+	// integers bits
+	uint8_t		u8 {0};
+	uint16_t	u16 {0};
+	uint32_t	u32 {0};
+	//uint64_t	u64 {0};
+
+	bool		b1 {false};
+
+	// integers ranges
+	uint8_t		r_u8 {0};
+	constexpr static MM::ScalarRange2<uint8_t> r_u8_r{10, 60};
+	int8_t		r_i8 {0};
+	constexpr static MM::ScalarRange2<int8_t> r_i8_r{-10, 5};
+	uint16_t	r_u16 {0};
+	constexpr static MM::ScalarRange2<uint16_t> r_u16_r{1, 1026};
+	int16_t		r_i16 {0};
+	constexpr static MM::ScalarRange2<int16_t> r_i16_r{-1, 1026};
+	uint32_t	r_u32 {0};
+	constexpr static MM::ScalarRange2<uint32_t> r_u32_r{0, 12341234};
+	int32_t		r_i32 {0};
+	constexpr static MM::ScalarRange2<int32_t> r_i32_r{-12341234, 10};
+
+	// floats
+	float		f32 {0.f};
+	double		f64 {0.};
+
+	// float compressed [0; 1] range
+	constexpr static float c0_f32_resolution = 0.001;
+	constexpr static MM::ScalarRange2<float> c0_f32_r{0.f, 1.f};
+	float		c0_f32_0 {0.f};
+	float		c0_f32_1 {0.f};
+	float		c0_f32_2 {0.f};
+	float		c0_f32_3 {0.f};
+
+	// float compressed [-1; 1] range
+	constexpr static float c1_f32_resolution = 0.05;
+	constexpr static MM::ScalarRange2<float> c1_f32_r{-1.f, 1.f};
+	float		c1_f32_0 {0.f};
+	float		c1_f32_1 {0.f};
+	float		c1_f32_2 {0.f};
+	float		c1_f32_3 {0.f};
+
+	// float compressed [-1000; 1000] range
+	constexpr static float c2_f32_resolution = 0.01;
+	constexpr static MM::ScalarRange2<float> c2_f32_r{-1000.f, 1000.f};
+	float		c2_f32_0 {0.f};
+	float		c2_f32_1 {0.f};
+	float		c2_f32_2 {0.f};
+	float		c2_f32_3 {0.f};
+};
+
+MM_DEFINE_SERIALIZE(TestStruct,
+	MM_S6ZER_BAIL(stream.serializeBits(data.u8))
+	MM_S6ZER_BAIL(stream.serializeBits(data.u16))
+	MM_S6ZER_BAIL(stream.serializeBits(data.u32))
+
+	MM_S6ZER_BAIL(stream.serializeBool(data.b1))
+
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_u8, data.r_u8_r.min(), data.r_u8_r.max()))
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_i8, data.r_i8_r.min(), data.r_i8_r.max()))
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_u16, data.r_u16_r.min(), data.r_u16_r.max()))
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_i16, data.r_i16_r.min(), data.r_i16_r.max()))
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_u32, data.r_u32_r.min(), data.r_u32_r.max()))
+	MM_S6ZER_BAIL(stream.serializeInt(data.r_i32, data.r_i32_r.min(), data.r_i32_r.max()))
+
+	MM_S6ZER_BAIL(stream.serializeFloat(data.f32))
+	MM_S6ZER_BAIL(stream.serializeDouble(data.f64))
+
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c0_f32_0, data.c0_f32_r.min(), data.c0_f32_r.max(), data.c0_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c0_f32_1, data.c0_f32_r.min(), data.c0_f32_r.max(), data.c0_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c0_f32_2, data.c0_f32_r.min(), data.c0_f32_r.max(), data.c0_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c0_f32_3, data.c0_f32_r.min(), data.c0_f32_r.max(), data.c0_f32_resolution))
+
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c1_f32_0, data.c1_f32_r.min(), data.c1_f32_r.max(), data.c1_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c1_f32_1, data.c1_f32_r.min(), data.c1_f32_r.max(), data.c1_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c1_f32_2, data.c1_f32_r.min(), data.c1_f32_r.max(), data.c1_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c1_f32_3, data.c1_f32_r.min(), data.c1_f32_r.max(), data.c1_f32_resolution))
+
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c2_f32_0, data.c2_f32_r.min(), data.c2_f32_r.max(), data.c2_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c2_f32_1, data.c2_f32_r.min(), data.c2_f32_r.max(), data.c2_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c2_f32_2, data.c2_f32_r.min(), data.c2_f32_r.max(), data.c2_f32_resolution))
+	MM_S6ZER_BAIL(stream.serializeFloatCompressed(data.c2_f32_3, data.c2_f32_r.min(), data.c2_f32_r.max(), data.c2_f32_resolution))
+)
+
+TEST(s6zer, stream_normalfull) {
+	std::array<uint32_t, 128> buffer;
+	size_t buffer_size = buffer.size()*sizeof(uint32_t);
+
+	MM::Random::SRNG rng{1337, 0};
+
+	const TestStruct data_in{
+		static_cast<uint8_t>(rng()),
+		static_cast<uint16_t>(rng()),
+		static_cast<uint32_t>(rng()),
+
+		rng.roll(0.5f),
+
+		rng.range(TestStruct::r_u8_r),
+		rng.range(TestStruct::r_i8_r),
+		rng.range(TestStruct::r_u16_r),
+		rng.range(TestStruct::r_i16_r),
+		rng.range(TestStruct::r_u32_r),
+		rng.range(TestStruct::r_i32_r),
+
+		rng.negOneToOne() * 10000000.f,
+		rng.negOneToOne() * 10000000.,
+
+		rng.range(TestStruct::c0_f32_r),
+		rng.range(TestStruct::c0_f32_r),
+		rng.range(TestStruct::c0_f32_r),
+		rng.range(TestStruct::c0_f32_r),
+
+		rng.range(TestStruct::c1_f32_r),
+		rng.range(TestStruct::c1_f32_r),
+		rng.range(TestStruct::c1_f32_r),
+		rng.range(TestStruct::c1_f32_r),
+
+		rng.range(TestStruct::c2_f32_r),
+		rng.range(TestStruct::c2_f32_r),
+		rng.range(TestStruct::c2_f32_r),
+		rng.range(TestStruct::c2_f32_r),
+	};
+
+	std::cout << "struct size: " << sizeof(TestStruct) << "\n";
+
+	{
+		MM::s6zer::StreamWriter writer{buffer.data(), buffer_size};
+
+		ASSERT_TRUE(mm_serialize(writer, data_in));
+
+		ASSERT_TRUE(writer.flush());
+		buffer_size = writer.bytesWritten();
+	}
+
+	std::cout << "buffer_size: " << buffer_size << "\n";
+
+	TestStruct data_out{}; // all zero
+
+	{
+		MM::s6zer::StreamReader reader{buffer.data(), buffer_size};
+
+		ASSERT_TRUE(mm_serialize(reader, data_out));
+
+		ASSERT_EQ(reader._scratch, 0x0000000000000000);
+	}
+
+	std::cout << "buffer: ";
+	for (size_t i = 0; i < buffer_size; i++) {
+		std::cout << std::hex << static_cast<uint32_t>(reinterpret_cast<uint8_t*>(buffer.data())[i]) << "'";
+	}
+	std::cout << "\n";
+
+	//std::cout << "data_out: \n" << data_out;
+
+	ASSERT_EQ(data_in.u8, data_out.u8);
+	ASSERT_EQ(data_in.u16, data_out.u16);
+	ASSERT_EQ(data_in.u32, data_out.u32);
+
+	ASSERT_EQ(data_in.b1, data_out.b1);
+
+	ASSERT_EQ(data_in.r_u8, data_out.r_u8) << "value range: " << TestStruct::r_u8_r;
+	ASSERT_EQ(data_in.r_i8, data_out.r_i8) << "value range: " << TestStruct::r_i8_r;
+	ASSERT_EQ(data_in.r_u16, data_out.r_u16) << "value range: " << TestStruct::r_u16_r;
+	ASSERT_EQ(data_in.r_i16, data_out.r_i16) << "value range: " << TestStruct::r_i16_r;
+	ASSERT_EQ(data_in.r_u32, data_out.r_u32) << "value range: " << TestStruct::r_u32_r;
+	ASSERT_EQ(data_in.r_i32, data_out.r_i32) << "value range: " << TestStruct::r_i32_r;
+
+	// bit perfect copies, can have wrong results for special values <.<
+	ASSERT_EQ(data_in.f32, data_out.f32);
+	ASSERT_EQ(data_in.f64, data_out.f64);
+
+	ASSERT_NEAR(data_in.c0_f32_0, data_out.c0_f32_0, TestStruct::c0_f32_resolution);
+	ASSERT_NEAR(data_in.c0_f32_1, data_out.c0_f32_1, TestStruct::c0_f32_resolution);
+	ASSERT_NEAR(data_in.c0_f32_2, data_out.c0_f32_2, TestStruct::c0_f32_resolution);
+	ASSERT_NEAR(data_in.c0_f32_3, data_out.c0_f32_3, TestStruct::c0_f32_resolution);
+
+	ASSERT_NEAR(data_in.c1_f32_0, data_out.c1_f32_0, TestStruct::c1_f32_resolution);
+	ASSERT_NEAR(data_in.c1_f32_1, data_out.c1_f32_1, TestStruct::c1_f32_resolution);
+	ASSERT_NEAR(data_in.c1_f32_2, data_out.c1_f32_2, TestStruct::c1_f32_resolution);
+	ASSERT_NEAR(data_in.c1_f32_3, data_out.c1_f32_3, TestStruct::c1_f32_resolution);
+
+	ASSERT_NEAR(data_in.c2_f32_0, data_out.c2_f32_0, TestStruct::c2_f32_resolution);
+	ASSERT_NEAR(data_in.c2_f32_1, data_out.c2_f32_1, TestStruct::c2_f32_resolution);
+	ASSERT_NEAR(data_in.c2_f32_2, data_out.c2_f32_2, TestStruct::c2_f32_resolution);
+	ASSERT_NEAR(data_in.c2_f32_3, data_out.c2_f32_3, TestStruct::c2_f32_resolution);
+}
+