> in a business setting where the very nature of what you build has to be arbitrarily mutable— I just don't use Haskell there. I personally use OCaml for my da

> in a business setting where the very nature of what you build has to be arbitrarily mutable— I just don't use Haskell there. I personally use OCaml for my data in, data out problems (compilers, generators…), but for inherently interactive and mutable stuff I just do imperative programming. Of course the type system (and the performance characteristics of the runtime!) must be suited to the problem domain. > burying details deep in type class patterns, relying on dozens of special case compiler directives to enhance Haskell... Looks like someone went overboard. I think you (your team?) should have been more conservative with the compiler directives, and less abstraction loving with the type classes.