GHC 8.2 includes a new -fhide-source-paths command-line flag that can be used to reduce line noise (disclaimer: I’m the author of the GHC patch introducing it).

To use it, just add the following in your stack.yaml file:

ghc-options:
   "$locals": -fhide-source-paths

Here is an example with one project of mine (first without the flag, second with the flag):

If you wonder why it isn’t enabled by default or where the flag name comes from, read the related tickets (#12807 and #12851) and the discussion on Phabricator (Phab:D2679, Phab:D2728).