[racket] Creating a #lang language, and modifying contract system

> Can someone please point me to documentation on how to create a language
> module so it can be used with #lang? I copied some module and hacked it
> until it worked, but I'm curious to know more details.


Sure!  Have you seen this section in the Guide?

    http://docs.racket-lang.org/guide/languages.html


If you'd like a whimsical, worked-out example, you can take a look at:

    http://hashcollision.org/brainfudge/


I hope this helps!