Compiling haskell for the JVM has been done before, several times. Sometimes even inside GHC. See for instance http://portal.acm.org/citation.cfm?id=968549 http://www.springerlink.com/content/w81yd3fljbrevuje/ http://wwwmail-archive.com/haskell@haskell.org/msg06673.html Regards, Malcolm Even if tail recursion is not properly supported, I've never really understood why this is an *total* impediment to getting it working on the JVM. I mean, yes it sucks, but there are ways to do it anyway (trampolining for one). They are usually _slow_ methods (which trampoline is), but if it's the difference between being able to run on the JVM and not, you would think that someone would think running on JVM slowly is better than not running on it at all... Maybe that's not the case though, maybe it would actually be bad for Haskell's rep to run slowly on JVM compared to other languages.