It's not a fork of CoffeeScript (though there are a lot of similarities). I'd initially tried doing that but I really couldn't get things to work the way I wanted. Mostly, it's a pretty major rearchitecture to get coffee to parse a function block that way.
I think syntax highlighting helps a lot in this case, so try out the tmbundle in Sublime or TextMate (https://github.com/rzimmerman/kal.tmbundle) if you can.