Hi, First off, being a windows user, having a configure/build separation seems a bit unusual. However, accepting that separation has been chosen, I was wondering what the design rationale for the following behaviour is: I download alex from darcs, runhaskell Setup configure checks for an absolute pile of things - such as alex, c2hs, cpphs - all things that are absolutely not required. In amongst all this waffle, it also checks for Happy - an absolute essential build dependancy. It doesn't find that, like it doesn't find plenty of other things, and continues straight along. Then when I try to buid, it fails. So the two points are: 1) Shouldn't configure check for what is required, rather than everything that any Haskell program might possibly require. 2) Shouldn't failing a configure check be an error, directing you to go get happy? Thanks Neil PS. I'm really liking this Cabal thing, its a very nice concept.