If you avoid circular refs and forward declarations by writing hierarchical code, you won't really need modules. In my current project I'm 20+ headers in and st

If you avoid circular refs and forward declarations by writing hierarchical code, you won't really need modules. In my current project I'm 20+ headers in and still haven't had a circular ref. Just refactor all the commonly used code, decouple with callbacks and you have yourself a nice clean header only library that you can amalgamate and/or precompile.