Data.List.Utils is part of the missingh library. If your app can't find it, it is probably not installed. cabal install missingh. To find out where a random import comes from, go to hackage.haskell.org, click on hayoo, and search for "Data.List.Utils". The ambiguous module name is totally different and doesn't happen very often anymore. Monads-fd used to be an improved version of mtl, and it exported roughly the same interface, but monads-fd is now deprecated and shouldn't be used. Sometimes when you load a file it ends up choosing it anyways, because it has to choose something. You can avoid that by typing ghci -hide-package=monads-fd. Alternatively you can use ghc-pkg hide to hide it permanently, so that nothing tries to use that, that should work.