I have a C app that I'd like to port to Squeak. I had this crazy idea that I wanted to incrementally replace parts of it bit by bit with Smalltalk, and was entertained by how that seemed roughly impossible. The first thought that crossed my mind was to try to bolt some sort of C-based RPC onto it, and use that as a way to get it to talk to Squeak. Then I thought about FFI, but what I'm reading about that talks specifically about libraries.