diff --git a/lua/ubus.c b/lua/ubus.c
index e2bb081..208da7d 100644
--- a/lua/ubus.c
+++ b/lua/ubus.c
@@ -51,6 +51,22 @@ struct ubus_lua_subscriber {
 static int
 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table);
 
+#if LUA_VERSION_NUM >= 503
+/* one can simply enable LUA_COMPAT_5_2 to be backward compatible.
+However, this does not work when we are trying to use system-installed lua,
+hence these redefines
+*/
+#define luaL_optlong(L,n,d)     ((long)luaL_optinteger(L, (n), (d)))
+#define luaL_optint(L,n,d)  	((int)luaL_optinteger(L, (n), (d)))
+#define luaL_checklong(L,n)     ((long)luaL_checkinteger(L, (n)))
+#define luaL_checkint(L,n)      ((int)luaL_checkinteger(L, (n)))
+
+#define lua_objlen(L,i)         (lua_rawlen(L, (i)))
+#define luaL_register(L,n,l)    (luaL_setfuncs(L,(l),0))
+
+#endif
+
+
 static int
 ubus_lua_parse_blob_array(lua_State *L, struct blob_attr *attr, size_t len, bool table)
 {