Where did I see it…there it is! Since you’re interested in Haskell2010:
https://downloads.haskell.org/~ghc/7.0.1/docs/html/users_guide/release-7-0-1.html
So gather some friends together, make a private fork of GHC 7.0.1 and have some fun!
…oh wait - it’s New “Haskell Compiler Group”, not New Haskell Compiler Group (darn).