Duetto is fully compatible with almost all C and C++ 11 code. You just need to add some tags to tell duetto if you want your methods compiled for the server or for the client. Everything else (including client to server and server to client remote procedure call, serialization and deserialization, etc.) will work automagically! The duetto compiler is based on the proven and robust LLVM stack.
So the current version is 0.9.3., so they are near the magic first stable release.
If you take a look into the example section, you get the picture pretty fast. A wiki page is also available. What its left to need, is some spare time :-).