Well, I mention Racket because it has extensive tooling for new language creation (I've seen C-like, Java-like, and SQL-like languages implemented in it), and they've done so much work in creating a very extensive standard library that compiles and optimizes down to relatively simple Scheme base language. You basically get tools and libraries and optimizations and other languages "for free" if you use Racket, much like with the CLR, but in a completely open-source, could-be-statically-compiled-if-you-want way.