ghcid

GHCi based bare bones IDE

Either "GHCi as a daemon" or "GHC + a bit of an IDE". A very simple Haskell development tool which shows you the errors in your project and updates them whenever you save. Run 'ghcid --topmost --command=ghci', where '--topmost' makes the window on top of all others (Windows only) and '--command' is the command to start GHCi on your project (defaults to 'ghci' if you have a '.ghci' file, or else to 'cabal repl').