Hi David,
I'm sorry to say but the project is currently dead and is no longer maintained. However, if you still you want to contribute, you can go ahead and I'll merge your patches/pullreqs, maybe you'll be the one to encourage me to work on it again? ;-)
Moreover, if you're looking to contribute to Open Source in general you can check out my repositories on GitHub and see what suits you. If you do not want to contribute to csnippets anymore after reading this, you can go for contributing to ccan which is a better version for C code (
github.com/rustyrussell/ccan).
Thanks!