Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: slack-notify-haskell (user goal)
rejecting: slack-notify-haskell-0.2.3, slack-notify-haskell-0.2.2,
slack-notify-haskell-0.2.1 (constraint from user target requires ==0.2)
rejecting: slack-notify-haskell-0.2 (conflict: slack-notify-haskell =>
slack-notify-haskell==0.1)
rejecting: slack-notify-haskell-0.1 (constraint from user target requires
==0.2)
Dependency tree exhaustively searched.