I've had a lot of problems with Stack whenever I'm doing non-trivial (that is, beyond just "build this executable the standard way") kinds of tasks—in particular, it tends to corrupt its package DB after a while for mysterious reasons, and you have to blow it away and rebuild, and it can be a nightmare to do certain bits of configuration where the UI is undocumented or nonexistant—but it's a pretty big step up from historical Cabal.

There's also an already-working-but-still-not-quite-finished alternative system within Cabal which is eventually gonna become the default one, and which does builds in a Nix-inspired way. I've been using that for the better part of a year now, and I like it far better than either historical Cabal or Stack: http://blog.ezyang.com/2016/05/announcing-cabal-new-build-ni...