diff --git a/include/luak/luak.h b/include/luak/luak.h
index 3a59ac5..0ca4fab 100644
--- a/include/luak/luak.h
+++ b/include/luak/luak.h
@@ -21,6 +21,7 @@ struct kiwmi_lua {
 };
 
 int luaK_callback_register_dispatch(lua_State *L);
+int luaK_usertype_ref_equal(lua_State *L);
 struct kiwmi_lua *luaK_create(struct kiwmi_server *server);
 bool luaK_dofile(struct kiwmi_lua *lua, const char *config_path);
 void luaK_destroy(struct kiwmi_lua *lua);
diff --git a/kiwmi/luak/kiwmi_cursor.c b/kiwmi/luak/kiwmi_cursor.c
index 9aaa788..8d30455 100644
--- a/kiwmi/luak/kiwmi_cursor.c
+++ b/kiwmi/luak/kiwmi_cursor.c
@@ -231,5 +231,8 @@ luaK_kiwmi_cursor_register(lua_State *L)
     luaL_newlib(L, kiwmi_cursor_events);
     lua_setfield(L, -2, "__events");
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
diff --git a/kiwmi/luak/kiwmi_keyboard.c b/kiwmi/luak/kiwmi_keyboard.c
index fbfd77a..3e56bad 100644
--- a/kiwmi/luak/kiwmi_keyboard.c
+++ b/kiwmi/luak/kiwmi_keyboard.c
@@ -191,5 +191,8 @@ luaK_kiwmi_keyboard_register(lua_State *L)
     luaL_newlib(L, kiwmi_keyboard_events);
     lua_setfield(L, -2, "__events");
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
diff --git a/kiwmi/luak/kiwmi_lua_callback.c b/kiwmi/luak/kiwmi_lua_callback.c
index b1f5dd6..0202d12 100644
--- a/kiwmi/luak/kiwmi_lua_callback.c
+++ b/kiwmi/luak/kiwmi_lua_callback.c
@@ -76,6 +76,9 @@ luaK_kiwmi_lua_callback_register(lua_State *L)
     lua_setfield(L, -2, "__index");
     luaL_setfuncs(L, kiwmi_lua_callback_methods, 0);
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
 
diff --git a/kiwmi/luak/kiwmi_output.c b/kiwmi/luak/kiwmi_output.c
index dbd8005..5347335 100644
--- a/kiwmi/luak/kiwmi_output.c
+++ b/kiwmi/luak/kiwmi_output.c
@@ -179,5 +179,8 @@ luaK_kiwmi_output_register(lua_State *L)
     luaL_newlib(L, kiwmi_output_events);
     lua_setfield(L, -2, "__events");
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
diff --git a/kiwmi/luak/kiwmi_server.c b/kiwmi/luak/kiwmi_server.c
index d953140..f27f4ae 100644
--- a/kiwmi/luak/kiwmi_server.c
+++ b/kiwmi/luak/kiwmi_server.c
@@ -273,5 +273,8 @@ luaK_kiwmi_server_register(lua_State *L)
     luaL_newlib(L, kiwmi_server_events);
     lua_setfield(L, -2, "__events");
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
diff --git a/kiwmi/luak/kiwmi_view.c b/kiwmi/luak/kiwmi_view.c
index 077fc82..4879ad1 100644
--- a/kiwmi/luak/kiwmi_view.c
+++ b/kiwmi/luak/kiwmi_view.c
@@ -267,5 +267,8 @@ luaK_kiwmi_view_register(lua_State *L)
     luaL_newlib(L, kiwmi_view_events);
     lua_setfield(L, -2, "__events");
 
+    lua_pushcfunction(L, luaK_usertype_ref_equal);
+    lua_setfield(L, -2, "__eq");
+
     return 0;
 }
diff --git a/kiwmi/luak/luak.c b/kiwmi/luak/luak.c
index 3552728..2f94fb7 100644
--- a/kiwmi/luak/luak.c
+++ b/kiwmi/luak/luak.c
@@ -47,6 +47,20 @@ luaK_callback_register_dispatch(lua_State *L)
     return 1;
 }
 
+int
+luaK_usertype_ref_equal(lua_State *L)
+{
+    luaL_checktype(L, 1, LUA_TUSERDATA);
+    luaL_checktype(L, 2, LUA_TUSERDATA);
+
+    void *a = *(void **)lua_touserdata(L, 1);
+    void *b = *(void **)lua_touserdata(L, 2);
+
+    lua_pushboolean(L, a == b);
+
+    return 1;
+}
+
 struct kiwmi_lua *
 luaK_create(struct kiwmi_server *server)
 {