I use it for my own experiments and never -- sadly -- for work, where my boss thinks Scala is just syntax sugar over Java, which is in turn merely syntax sugar over C. I don't think he has ever heard of Haskell, and I don't have the energy to have that conversation with him, when he is already so dismissive of Scala.
But I still have ghci installed at work, and I find it surprisingly useful to use Haskell to prototype (pure) functions for Scala! This is something I truly didn't see coming, but now I often find myself starting ghci when I want to see if some combination of folds or maps works the way I think it should, and for some reason it feels way more convenient than trying it in Scala.
C is just portable assembler, ask him why he's got people wasting company time and cpu cycles on such a thing. I'm sure you're targeting x86, time to put on your big boy pants.
But I still have ghci installed at work, and I find it surprisingly useful to use Haskell to prototype (pure) functions for Scala! This is something I truly didn't see coming, but now I often find myself starting ghci when I want to see if some combination of folds or maps works the way I think it should, and for some reason it feels way more convenient than trying it in Scala.