I am looking for a solution for my C++/lua engine. I would like my game to become multiplayer, but without making an entirely new server codebase. (code for client and server should be the same). I am thinking internal server, but how it this implemented and what challenges should I expect? The most important thing is that it would be easy to use and expand on. I know Minecraft / space enginers and some other games can sync the data of objects and so on without hosting a server. Has anyone got an idea for how to do something like this? maybe some articles?