Resolving dependencies... cabal: Could not resolve dependencies: next goal: yesod-pnotify (user goal) rejecting: yesod-pnotify-1.1.2, 1.1.1, 1.1.0, 1.0.2, 1.0.1, 1.0.0, 0.6.0, 0.5.0, 0.4.4.1, 0.4.4.0, 0.4.3.0, 0.4.2.0, 0.4.1.0, 0.4.0.1, 0.4.0.0, 0.3.0.0, 0.2.0.0 (global constraint requires ==0.1.0.0) trying: yesod-pnotify-0.1.0.0 next goal: base (dependency of yesod-pnotify-0.1.0.0) rejecting: base-4.8.1.0/installed-4f7... (conflict: yesod-pnotify => base==4.5.*) rejecting: base-4.8.1.0, 4.8.0.0, 4.7.0.2, 4.7.0.1, 4.7.0.0, 4.6.0.1, 4.6.0.0, 4.5.1.0, 4.5.0.0, 4.4.1.0, 4.4.0.0, 4.3.1.0, 4.3.0.0, 4.2.0.2, 4.2.0.1, 4.2.0.0, 4.1.0.0, 4.0.0.0, 3.0.3.2, 3.0.3.1 (global constraint requires installed instance) Dependency tree exhaustively searched.