i've pushed a state that is pretty functional, i'd call it a v1.0 beta:
https://github.com/attila-lendvai/cffi
and here's an example project that uses it:
https://github.com/attila-lendvai/hu.dwim.bluez
the ASDF part probably needs some care, espcially the recompilation dependency checking, but it's beyond me. the shared ASDF parts of cffi-grovel should also be factored out. i'm hoping to convince Fare with something to deal with it.