The new CoffeeScript self compiler uses Jison for generating the parser. The whole build script runs on Node.
Jeremy, the creator of CoffeeScript, spurred me to make some quick performance improvements (and bug fixes) to Jison so that the CoffeeScript grammar could build in a timely fashion. And while there are still many improvements to be made, handling such a large and complex grammar is quite a feat!
Jeremy also reported that parsing times are quick, though that's more of a testament to v8, I'm sure.
