> And null pointer exceptions? They only happen to me very rarely, when I quickly hack something together and then it is a "oh forgot - and fixed" problem.

And you never run into NPEs in production? It's something you always discover during development? How?

> The problems I do struggle with are non reproducable race condition fun etc. and I doubt haskell could help me with them.

In a pure system, thread race conditions are impossible. You can still get race conditions for your external effects, which is unavoidable.