Have a look at Jonathan Worthington's slides (http://www.jnthn.net/papers/2011-yapc-russia-compiler.pdf). The code is next door on his web site. But as this was a public talk, there may be a recording of it on YAPC.tv. My spies tell me that the talk was outstanding, writing a complete language (well, almost) from next to nothing in under an hour.

Regards,

John Davies