Interesting, I'm planning to implement a translator from a subset of Scheme to Rust. The source code will be Scheme plus extraneous forms for declaring types and borrow checker information / referencing, minus support for call/cc and other difficult to translate Scheme features. I want to develop a program in a Scheme interpreter then be able to compile it as a Rust program. Contact me if interested (and meet me in London via http://rustaceans.uk).