Warning: The install command is a part of the legacy v1 style of cabal usage. Please switch to using either the new project style and the new-install command or the legacy v1-install alias as new-style projects will become the default in the next version of cabal-install. Please file a bug if you cannot replicate a working v1- use case with the new-style commands. For more information, see: https://wiki.haskell.org/Cabal/NewBuild Resolving dependencies... Downloading pidfile-0.1.0.4 Downloaded pidfile-0.1.0.4 Starting pidfile-0.1.0.4 Building pidfile-0.1.0.4 Completed pidfile-0.1.0.4