diff --git a/plugins/plugin_mfs_wip.cpp b/plugins/plugin_mfs_wip.cpp
index 2ab024f..695568f 100644
--- a/plugins/plugin_mfs_wip.cpp
+++ b/plugins/plugin_mfs_wip.cpp
@@ -34,7 +34,7 @@ SOLANA_PLUGIN_EXPORT uint32_t solana_plugin_start(struct SolanaAPI* solana_api)
 	}
 
 	try {
-		auto* cr = PLUG_RESOLVE_INSTANCE_VERSIONED(Contact3Registry, "1");
+		auto* cs = PLUG_RESOLVE_INSTANCE(ContactStore4I);
 		auto* rmm = PLUG_RESOLVE_INSTANCE(RegistryMessageModelI);
 		auto* os = PLUG_RESOLVE_INSTANCE(ObjectStore2);
 		auto* msnj = PLUG_RESOLVE_INSTANCE(MessageSerializerNJ);
@@ -42,7 +42,7 @@ SOLANA_PLUGIN_EXPORT uint32_t solana_plugin_start(struct SolanaAPI* solana_api)
 		// static store, could be anywhere tho
 		// construct with fetched dependencies
 		g_fsb = std::make_unique<Backends::FilesystemStorage>(*os, "test2_message_store/"); // TODO: use config?
-		g_mfs = std::make_unique<MessageFragmentStore>(*cr, *rmm, *os, *g_fsb, *g_fsb, *msnj);
+		g_mfs = std::make_unique<MessageFragmentStore>(*cs, *rmm, *os, *g_fsb, *g_fsb, *msnj);
 
 		// register types
 		PLUG_PROVIDE_INSTANCE(MessageFragmentStore, plugin_name, g_mfs.get());
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 93cf2d6..f4d3c4f 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -28,6 +28,7 @@ add_executable(convert_message_object_store
 )
 
 target_link_libraries(convert_message_object_store PUBLIC
+	solanaceae_contact_impl
 	solanaceae_object_store
 	solanaceae_object_store_backend_filesystem
 	solanaceae_message_fragment_store
diff --git a/src/convert_frag_to_obj.cpp b/src/convert_frag_to_obj.cpp
index 8401890..43e539e 100644
--- a/src/convert_frag_to_obj.cpp
+++ b/src/convert_frag_to_obj.cpp
@@ -1,3 +1,4 @@
+#include <solanaceae/contact/contact_store_impl.hpp>
 #include <solanaceae/object_store/object_store.hpp>
 #include <solanaceae/object_store/backends/filesystem_storage.hpp>
 #include <solanaceae/object_store/meta_components.hpp>
@@ -35,14 +36,14 @@ int main(int argc, const char** argv) {
 	Backends::FilesystemStorage fsb_src(os_src, argv[1]);
 	Backends::FilesystemStorage fsb_dst(os_dst, argv[2]);
 
-	Contact3Registry cr; // dummy
-	RegistryMessageModelImpl rmm(cr); // dummy
+	ContactStore4Impl cs; // dummy
+	RegistryMessageModelImpl rmm(cs); // dummy
 	// they only exist for the serializers (for now)
 	// TODO: version
-	MessageSerializerNJ msnj_src{cr, os_src, {}, {}};
-	MessageFragmentStore mfs_src(cr, rmm, os_src, fsb_src, fsb_src, msnj_src);
-	MessageSerializerNJ msnj_dst{cr, os_dst, {}, {}};
-	MessageFragmentStore mfs_dst(cr, rmm, os_dst, fsb_dst, fsb_dst, msnj_dst);
+	MessageSerializerNJ msnj_src{cs, os_src, {}, {}};
+	MessageFragmentStore mfs_src(cs, rmm, os_src, fsb_src, fsb_src, msnj_src);
+	MessageSerializerNJ msnj_dst{cs, os_dst, {}, {}};
+	MessageFragmentStore mfs_dst(cs, rmm, os_dst, fsb_dst, fsb_dst, msnj_dst);
 
 	// add message fragment store too (adds meta?)
 
diff --git a/src/solanaceae/message_fragment_store/message_fragment_store.cpp b/src/solanaceae/message_fragment_store/message_fragment_store.cpp
index c2e1a43..cb3b943 100644
--- a/src/solanaceae/message_fragment_store/message_fragment_store.cpp
+++ b/src/solanaceae/message_fragment_store/message_fragment_store.cpp
@@ -9,6 +9,8 @@
 #include <solanaceae/util/utils.hpp>
 #include <solanaceae/util/time.hpp>
 
+#include <solanaceae/contact/contact_store_i.hpp>
+
 #include <solanaceae/contact/components.hpp>
 #include <solanaceae/message3/components.hpp>
 #include <solanaceae/message3/contact_components.hpp>
@@ -37,7 +39,7 @@ namespace ObjectStore::Components {
 
 		// cache the contact for faster lookups
 		struct MessagesContactEntity {
-			Contact3 e {entt::null};
+			Contact4 e {entt::null};
 		};
 	}
 } // ObjectStore::Component
@@ -83,8 +85,8 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 		return; // we only handle msg with ts
 	}
 
-	_potentially_dirty_contacts.emplace(m.registry()->ctx().get<Contact3>()); // always mark dirty here
-	_touched_contacts.emplace(m.registry()->ctx().get<Contact3>());
+	_potentially_dirty_contacts.emplace(m.registry()->ctx().get<Contact4>()); // always mark dirty here
+	_touched_contacts.emplace(m.registry()->ctx().get<Contact4>());
 	if (m.any_of<Message::Components::ViewCurserBegin, Message::Components::ViewCurserEnd>()) {
 		// not an actual message, but we probalby need to check and see if we need to load fragments
 		//std::cout << "MFS: new or updated curser\n";
@@ -206,9 +208,9 @@ void MessageFragmentStore::handleMessage(const Message3Handle& m) {
 			new_ts_range.end = msg_ts;
 
 			{
-				const auto msg_reg_contact = m.registry()->ctx().get<Contact3>();
-				if (_cr.all_of<Contact::Components::ID>(msg_reg_contact)) {
-					fh.emplace<ObjComp::MessagesContact>(_cr.get<Contact::Components::ID>(msg_reg_contact).data);
+				const auto msg_reg_contact = m.registry()->ctx().get<Contact4>();
+				if (_cs.registry().all_of<Contact::Components::ID>(msg_reg_contact)) {
+					fh.emplace<ObjComp::MessagesContact>(_cs.registry().get<Contact::Components::ID>(msg_reg_contact).data);
 				} else {
 					// ? rage quit?
 				}
@@ -364,10 +366,10 @@ void MessageFragmentStore::loadFragment(Message3Registry& reg, ObjectHandle fh)
 		Message3 dup_msg {entt::null};
 		{
 			// get comparator from contact
-			if (reg.ctx().contains<Contact3>()) {
-				const auto c = reg.ctx().get<Contact3>();
-				if (_cr.all_of<Contact::Components::MessageIsSame>(c)) {
-					auto& comp = _cr.get<Contact::Components::MessageIsSame>(c).comp;
+			if (reg.ctx().contains<Contact4>()) {
+				const auto c = reg.ctx().get<Contact4>();
+				if (_cs.registry().all_of<Contact::Components::MessageIsSame>(c)) {
+					auto& comp = _cs.registry().get<Contact::Components::MessageIsSame>(c).comp;
 					// walking EVERY existing message OOF
 					// this needs optimizing
 					for (const Message3 other_msg : reg.view<Message::Components::Timestamp, Message::Components::ContactFrom, Message::Components::ContactTo>()) {
@@ -504,13 +506,13 @@ bool MessageFragmentStore::syncFragToStorage(ObjectHandle fh, Message3Registry&
 }
 
 MessageFragmentStore::MessageFragmentStore(
-	Contact3Registry& cr,
+	ContactStore4I& cs,
 	RegistryMessageModelI& rmm,
 	ObjectStore2& os,
 	StorageBackendIMeta& sbm,
 	StorageBackendIAtomic& sba,
 	MessageSerializerNJ& scnj
-) : _cr(cr), _rmm(rmm), _rmm_sr(_rmm.newSubRef(this)), _os(os), _os_sr(_os.newSubRef(this)), _sbm(sbm), _sba(sba), _scnj(scnj) {
+) : _cs(cs), _rmm(rmm), _rmm_sr(_rmm.newSubRef(this)), _os(os), _os_sr(_os.newSubRef(this)), _sbm(sbm), _sba(sba), _scnj(scnj) {
 	_rmm_sr
 		.subscribe(RegistryMessageModel_Event::message_construct)
 		.subscribe(RegistryMessageModel_Event::message_updated)
@@ -867,17 +869,17 @@ bool MessageFragmentStore::onEvent(const ObjectStore::Events::ObjectConstruct& e
 
 	// TODO: are we sure it is a *new* fragment?
 
-	Contact3 frag_contact = entt::null;
+	Contact4 frag_contact = entt::null;
 	{ // get contact
 		const auto& frag_contact_id = e.e.get<ObjComp::MessagesContact>().id;
 		// TODO: id lookup table, this is very inefficent
-		for (const auto& [c_it, id_it] : _cr.view<Contact::Components::ID>().each()) {
+		for (const auto& [c_it, id_it] : _cs.registry().view<Contact::Components::ID>().each()) {
 			if (frag_contact_id == id_it.data) {
 				frag_contact = c_it;
 				break;
 			}
 		}
-		if (!_cr.valid(frag_contact)) {
+		if (!_cs.registry().valid(frag_contact)) {
 			// unkown contact
 			return false;
 		}
@@ -917,23 +919,23 @@ bool MessageFragmentStore::onEvent(const ObjectStore::Events::ObjectUpdate& e) {
 	// its also possible it was tagged as empty
 	e.e.remove<ObjComp::Ephemeral::MessagesEmptyTag>();
 
-	Contact3 frag_contact = entt::null;
+	Contact4 frag_contact = entt::null;
 	{ // get contact
 		// probably cached already
 		if (e.e.all_of<ObjComp::Ephemeral::MessagesContactEntity>()) {
 			frag_contact = e.e.get<ObjComp::Ephemeral::MessagesContactEntity>().e;
 		}
 
-		if (!_cr.valid(frag_contact)) {
+		if (!_cs.registry().valid(frag_contact)) {
 			const auto& frag_contact_id = e.e.get<ObjComp::MessagesContact>().id;
 			// TODO: id lookup table, this is very inefficent
-			for (const auto& [c_it, id_it] : _cr.view<Contact::Components::ID>().each()) {
+			for (const auto& [c_it, id_it] : _cs.registry().view<Contact::Components::ID>().each()) {
 				if (frag_contact_id == id_it.data) {
 					frag_contact = c_it;
 					break;
 				}
 			}
-			if (!_cr.valid(frag_contact)) {
+			if (!_cs.registry().valid(frag_contact)) {
 				// unkown contact
 				return false;
 			}
diff --git a/src/solanaceae/message_fragment_store/message_fragment_store.hpp b/src/solanaceae/message_fragment_store/message_fragment_store.hpp
index f883920..614e5d2 100644
--- a/src/solanaceae/message_fragment_store/message_fragment_store.hpp
+++ b/src/solanaceae/message_fragment_store/message_fragment_store.hpp
@@ -12,7 +12,7 @@
 #include <entt/container/dense_map.hpp>
 #include <entt/container/dense_set.hpp>
 
-#include <solanaceae/contact/contact_model3.hpp>
+#include <solanaceae/contact/fwd.hpp>
 #include <solanaceae/message3/registry_message_model.hpp>
 
 #include <deque>
@@ -50,7 +50,7 @@ class MessageFragmentStore : public RegistryMessageModelEventI, public ObjectSto
 		static constexpr const char* version {"3"};
 
 	protected:
-		Contact3Registry& _cr;
+		ContactStore4I& _cs;
 		RegistryMessageModelI& _rmm;
 		RegistryMessageModelI::SubscriptionReference _rmm_sr;
 		ObjectStore2& _os;
@@ -78,21 +78,21 @@ class MessageFragmentStore : public RegistryMessageModelEventI, public ObjectSto
 
 		struct ECQueueEntry final {
 			ObjectHandle fid;
-			Contact3 c;
+			Contact4 c;
 		};
 		std::deque<ECQueueEntry> _event_check_queue;
 
 		// range changed or fragment loaded.
 		// we only load a limited number of fragments at once,
 		// so we need to keep them dirty until nothing was loaded.
-		entt::dense_set<Contact3> _potentially_dirty_contacts;
+		entt::dense_set<Contact4> _potentially_dirty_contacts;
 
 		// for cleaning up the ctx vars we create
-		entt::dense_set<Contact3> _touched_contacts;
+		entt::dense_set<Contact4> _touched_contacts;
 
 	public:
 		MessageFragmentStore(
-			Contact3Registry& cr,
+			ContactStore4I& cr,
 			RegistryMessageModelI& rmm,
 			ObjectStore2& os,
 			StorageBackendIMeta& sbm,