One of the things I love Haskell for, and there are many reasons, is that it's great at building compilers and interpreters. Monadic transformers for effects, pattern matching in functions, strong types, polymorphic typeclasses, the list goes on and on.

Finally, if anyone is interested in building something like this, there is a great tutorial that, which I believe the author used but am not sure: http://www.stephendiehl.com/llvm/