As far as I'm aware Chez Scheme will become the language engine for the Racket family of languages replacing the current language engine. I mean, Racket used to

As far as I'm aware Chez Scheme will become the language engine for the Racket family of languages replacing the current language engine. I mean, Racket used to be PLT Scheme, we're not talking a huge leap language-wise here, it's that the Chez Scheme back-end implementation is of very high quality. Racket has a lot of front-end stuff going on that Chez Scheme doesn't. I'm totally open to correction here from those with more familiarity. I am far from an expert on these matters. If you dig into the repos and docs that have been linked and read around for a bit you'll have as much knowledge as me :)