diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 09d10aa..ffd0531 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -10,15 +10,16 @@ add_library(fragment_store
 	./fragment_store/types.hpp
 	./fragment_store/meta_components.hpp
 	./fragment_store/meta_components_id.inl
-	./fragment_store/serializer.hpp
 	./fragment_store/file2_stack.hpp
 	./fragment_store/file2_stack.cpp
 	#old
+	./fragment_store/serializer.hpp
 	./fragment_store/fragment_store_i.hpp
 	./fragment_store/fragment_store_i.cpp
 	./fragment_store/fragment_store.hpp
 	./fragment_store/fragment_store.cpp
 	#new
+	./fragment_store/serializer_json.hpp
 	./fragment_store/object_store.hpp
 	./fragment_store/object_store.cpp
 	./fragment_store/backends/filesystem_storage.hpp
diff --git a/src/fragment_store/backends/filesystem_storage.cpp b/src/fragment_store/backends/filesystem_storage.cpp
index 222a971..b5ae420 100644
--- a/src/fragment_store/backends/filesystem_storage.cpp
+++ b/src/fragment_store/backends/filesystem_storage.cpp
@@ -1,6 +1,7 @@
 #include "./filesystem_storage.hpp"
 
 #include "../meta_components.hpp"
+#include "../serializer_json.hpp"
 
 #include <solanaceae/util/utils.hpp>
 
@@ -38,60 +39,10 @@ static ByteSpan spanFromRead(const std::variant<ByteSpan, std::vector<uint8_t>>&
 	}
 }
 
-// TODO: move somewhere else
-static bool serl_json_data_enc_type(const ObjectHandle oh, nlohmann::json& out) {
-	if (!oh.all_of<ObjComp::DataEncryptionType>()) {
-		return false;
-	}
-
-	out = static_cast<std::underlying_type_t<Encryption>>(
-		oh.get<ObjComp::DataEncryptionType>().enc
-	);
-	return true;
-}
-
-static bool deserl_json_data_enc_type(ObjectHandle oh, const nlohmann::json& in) {
-	oh.emplace_or_replace<ObjComp::DataEncryptionType>(
-		static_cast<Encryption>(
-			static_cast<std::underlying_type_t<Encryption>>(in)
-		)
-	);
-	return true;
-}
-
-static bool serl_json_data_comp_type(const ObjectHandle oh, nlohmann::json& out) {
-	if (!oh.all_of<ObjComp::DataCompressionType>()) {
-		return false;
-	}
-
-	out = static_cast<std::underlying_type_t<Compression>>(
-		oh.get<ObjComp::DataCompressionType>().comp
-	);
-	return true;
-}
-
-static bool deserl_json_data_comp_type(ObjectHandle oh, const nlohmann::json& in) {
-	oh.emplace_or_replace<ObjComp::DataCompressionType>(
-		static_cast<Compression>(
-			static_cast<std::underlying_type_t<Compression>>(in)
-		)
-	);
-	return true;
-}
 
 namespace backend {
 
 FilesystemStorage::FilesystemStorage(ObjectStore2& os, std::string_view storage_path) : StorageBackendI::StorageBackendI(os), _storage_path(storage_path) {
-	_sc.registerSerializerJson<ObjComp::DataEncryptionType>(serl_json_data_enc_type);
-	_sc.registerDeSerializerJson<ObjComp::DataEncryptionType>(deserl_json_data_enc_type);
-	_sc.registerSerializerJson<ObjComp::DataCompressionType>(serl_json_data_comp_type);
-	_sc.registerDeSerializerJson<ObjComp::DataCompressionType>(deserl_json_data_comp_type);
-
-	// old stuff
-	_sc.registerSerializerJson<FragComp::DataEncryptionType>(serl_json_data_enc_type);
-	_sc.registerDeSerializerJson<FragComp::DataEncryptionType>(deserl_json_data_enc_type);
-	_sc.registerSerializerJson<FragComp::DataCompressionType>(serl_json_data_comp_type);
-	_sc.registerDeSerializerJson<FragComp::DataCompressionType>(deserl_json_data_comp_type);
 }
 
 FilesystemStorage::~FilesystemStorage(void) {
@@ -227,6 +178,8 @@ bool FilesystemStorage::write(Object o, std::function<write_to_storage_fetch_dat
 		nlohmann::json meta_data_j = nlohmann::json::object(); // metadata needs to be an object, null not allowed
 		// metadata file
 
+		auto& sjc = _os.registry().ctx().get<SerializerJsonCallbacks<Object>>();
+
 		// TODO: refactor extract to OS
 		for (const auto& [type_id, storage] : reg.storage()) {
 			if (!storage.contains(o)) {
@@ -236,8 +189,8 @@ bool FilesystemStorage::write(Object o, std::function<write_to_storage_fetch_dat
 			//std::cout << "storage type: type_id:" << type_id << " name:" << storage.type().name() << "\n";
 
 			// use type_id to find serializer
-			auto s_cb_it = _sc._serl_json.find(type_id);
-			if (s_cb_it == _sc._serl_json.end()) {
+			auto s_cb_it = sjc._serl.find(type_id);
+			if (s_cb_it == sjc._serl.end()) {
 				// could not find serializer, not saving
 				continue;
 			}
@@ -527,6 +480,8 @@ size_t FilesystemStorage::scanPath(std::string_view path) {
 		}
 	}
 
+	auto& sjc = _os.registry().ctx().get<SerializerJsonCallbacks<Object>>();
+
 	std::vector<Object> scanned_objs;
 	// step 3: parse meta and insert into reg of non preexising
 	// main thread
@@ -637,8 +592,8 @@ size_t FilesystemStorage::scanPath(std::string_view path) {
 		for (const auto& [k, v] : j.items()) {
 			// type id from string hash
 			const auto type_id = entt::hashed_string(k.data(), k.size());
-			const auto deserl_fn_it = _sc._deserl_json.find(type_id);
-			if (deserl_fn_it != _sc._deserl_json.cend()) {
+			const auto deserl_fn_it = sjc._deserl.find(type_id);
+			if (deserl_fn_it != sjc._deserl.cend()) {
 				// TODO: check return value
 				deserl_fn_it->second(oh, v);
 			} else {
diff --git a/src/fragment_store/backends/filesystem_storage.hpp b/src/fragment_store/backends/filesystem_storage.hpp
index ef5c111..626f000 100644
--- a/src/fragment_store/backends/filesystem_storage.hpp
+++ b/src/fragment_store/backends/filesystem_storage.hpp
@@ -26,11 +26,6 @@ struct FilesystemStorage : public StorageBackendI {
 	private:
 		size_t scanPath(std::string_view path);
 		void scanPathAsync(std::string path);
-
-	public: // TODO: private?
-		// this thing needs to change and be facilitated over the OS
-		// but the json serializer are specific to the backend
-		SerializerCallbacks<Object> _sc;
 };
 
 } // backend
diff --git a/src/fragment_store/convert_frag_to_obj.cpp b/src/fragment_store/convert_frag_to_obj.cpp
index 0329212..7d36bfa 100644
--- a/src/fragment_store/convert_frag_to_obj.cpp
+++ b/src/fragment_store/convert_frag_to_obj.cpp
@@ -1,6 +1,7 @@
 #include "./object_store.hpp"
 #include "./backends/filesystem_storage.hpp"
 #include "./meta_components.hpp"
+#include "./serializer_json.hpp"
 
 #include <solanaceae/util/utils.hpp>
 
@@ -97,7 +98,7 @@ int main(int argc, const char** argv) {
 					oh.emplace_or_replace<ObjComp::Ephemeral::MetaCompressionType>(e.e.get_or_emplace<ObjComp::Ephemeral::MetaCompressionType>());
 
 					// serializable
-					for (const auto& [type, fn] : _fsb_src._sc._serl_json) {
+					for (const auto& [type, fn] : _os_src.registry().ctx().get<SerializerJsonCallbacks<Object>>()._serl) {
 						//if (!e.e.registry()->storage(type)->contains(e.e)) {
 							//continue;
 						//}
@@ -106,7 +107,7 @@ int main(int argc, const char** argv) {
 						// raw copy might be better in the future
 						nlohmann::json tmp_j;
 						if (fn(e.e, tmp_j)) {
-							_fsb_dst._sc._deserl_json.at(type)(oh, tmp_j);
+							_os_dst.registry().ctx().get<SerializerJsonCallbacks<Object>>()._deserl.at(type)(oh, tmp_j);
 						}
 					}
 				}
diff --git a/src/fragment_store/object_store.cpp b/src/fragment_store/object_store.cpp
index 663d1f9..d5e2dae 100644
--- a/src/fragment_store/object_store.cpp
+++ b/src/fragment_store/object_store.cpp
@@ -2,10 +2,53 @@
 
 #include "./meta_components.hpp"
 
+#include "./serializer_json.hpp"
+
 #include <nlohmann/json.hpp> // this sucks
 
 #include <iostream>
 
+// TODO: move somewhere else
+static bool serl_json_data_enc_type(const ObjectHandle oh, nlohmann::json& out) {
+	if (!oh.all_of<ObjComp::DataEncryptionType>()) {
+		return false;
+	}
+
+	out = static_cast<std::underlying_type_t<Encryption>>(
+		oh.get<ObjComp::DataEncryptionType>().enc
+	);
+	return true;
+}
+
+static bool deserl_json_data_enc_type(ObjectHandle oh, const nlohmann::json& in) {
+	oh.emplace_or_replace<ObjComp::DataEncryptionType>(
+		static_cast<Encryption>(
+			static_cast<std::underlying_type_t<Encryption>>(in)
+		)
+	);
+	return true;
+}
+
+static bool serl_json_data_comp_type(const ObjectHandle oh, nlohmann::json& out) {
+	if (!oh.all_of<ObjComp::DataCompressionType>()) {
+		return false;
+	}
+
+	out = static_cast<std::underlying_type_t<Compression>>(
+		oh.get<ObjComp::DataCompressionType>().comp
+	);
+	return true;
+}
+
+static bool deserl_json_data_comp_type(ObjectHandle oh, const nlohmann::json& in) {
+	oh.emplace_or_replace<ObjComp::DataCompressionType>(
+		static_cast<Compression>(
+			static_cast<std::underlying_type_t<Compression>>(in)
+		)
+	);
+	return true;
+}
+
 StorageBackendI::StorageBackendI(ObjectStore2& os) : _os(os) {
 }
 
@@ -23,6 +66,18 @@ bool StorageBackendI::write(Object o, const ByteSpan data) {
 }
 
 ObjectStore2::ObjectStore2(void) {
+	// HACK: set them up independently
+	auto& sjc = _reg.ctx().emplace<SerializerJsonCallbacks<Object>>();
+	sjc.registerSerializer<ObjComp::DataEncryptionType>(serl_json_data_enc_type);
+	sjc.registerDeSerializer<ObjComp::DataEncryptionType>(deserl_json_data_enc_type);
+	sjc.registerSerializer<ObjComp::DataCompressionType>(serl_json_data_comp_type);
+	sjc.registerDeSerializer<ObjComp::DataCompressionType>(deserl_json_data_comp_type);
+
+	// old stuff
+	sjc.registerSerializer<FragComp::DataEncryptionType>(serl_json_data_enc_type);
+	sjc.registerDeSerializer<FragComp::DataEncryptionType>(deserl_json_data_enc_type);
+	sjc.registerSerializer<FragComp::DataCompressionType>(serl_json_data_comp_type);
+	sjc.registerDeSerializer<FragComp::DataCompressionType>(deserl_json_data_comp_type);
 }
 
 ObjectStore2::~ObjectStore2(void) {
diff --git a/src/fragment_store/object_store.hpp b/src/fragment_store/object_store.hpp
index fcc4456..03bac9b 100644
--- a/src/fragment_store/object_store.hpp
+++ b/src/fragment_store/object_store.hpp
@@ -3,8 +3,6 @@
 #include <solanaceae/util/event_provider.hpp>
 #include <solanaceae/util/span.hpp>
 
-#include "./serializer.hpp" // TODO: get rid of the tight nljson integration
-
 #include <entt/entity/registry.hpp>
 #include <entt/entity/handle.hpp>
 
diff --git a/src/fragment_store/serializer_json.hpp b/src/fragment_store/serializer_json.hpp
new file mode 100644
index 0000000..cd74540
--- /dev/null
+++ b/src/fragment_store/serializer_json.hpp
@@ -0,0 +1,67 @@
+#pragma once
+
+#include <entt/core/type_info.hpp>
+#include <entt/container/dense_map.hpp>
+#include <entt/entity/handle.hpp>
+
+#include <nlohmann/json_fwd.hpp>
+
+// nlohmann
+template<typename EntityType = entt::entity>
+struct SerializerJsonCallbacks {
+	using Registry = entt::basic_registry<EntityType>;
+	using Handle = entt::basic_handle<Registry>;
+
+	using serialize_fn = bool(*)(const Handle h, nlohmann::json& out);
+	entt::dense_map<entt::id_type, serialize_fn> _serl;
+
+	using deserialize_fn = bool(*)(Handle h, const nlohmann::json& in);
+	entt::dense_map<entt::id_type, deserialize_fn> _deserl;
+
+	template<typename T>
+	static bool component_get_json(const Handle h, nlohmann::json& j) {
+		if (h.template all_of<T>()) {
+			if constexpr (!std::is_empty_v<T>) {
+				j = h.template get<T>();
+			}
+			return true;
+		}
+
+		return false;
+	}
+
+	template<typename T>
+	static bool component_emplace_or_replace_json(Handle h, const nlohmann::json& j) {
+		if constexpr (std::is_empty_v<T>) {
+			h.template emplace_or_replace<T>(); // assert empty json?
+		} else {
+			h.template emplace_or_replace<T>(static_cast<T>(j));
+		}
+		return true;
+	}
+
+	void registerSerializer(serialize_fn fn, const entt::type_info& type_info) {
+		_serl[type_info.hash()] = fn;
+	}
+
+	template<typename CompType>
+	void registerSerializer(
+		serialize_fn fn = component_get_json<CompType>,
+		const entt::type_info& type_info = entt::type_id<CompType>()
+	) {
+		registerSerializer(fn, type_info);
+	}
+
+	void registerDeSerializer(deserialize_fn fn, const entt::type_info& type_info) {
+		_deserl[type_info.hash()] = fn;
+	}
+
+	template<typename CompType>
+	void registerDeSerializer(
+		deserialize_fn fn = component_emplace_or_replace_json<CompType>,
+		const entt::type_info& type_info = entt::type_id<CompType>()
+	) {
+		registerDeSerializer(fn, type_info);
+	}
+};
+