Feh. It's going to require COORDINATION. Which is why I say the bulk of your functions should be in external files, for instance, if I made a new file for g_ code, I'd call it g_wu_whatever.c - and I'd have some step by step code pastes for hooking it up to the main codebase. It's the least ugly way to go about it.
Every other way, checking, single code-base, etc - they just seem too problematic and klunky. I just want to code.
I made a silly little program called Dragon, which is an animation tool for the GLA format, used in Jedi Outcast, Jedi Academy and Krakatoa.