Resolving dependencies... cabal: Could not resolve dependencies: next goal: git-fmt (user goal) rejecting: git-fmt-0.4.1.0, git-fmt-0.4.0.0, git-fmt-0.3.1.2, git-fmt-0.3.1.1, git-fmt-0.3.1.0, git-fmt-0.3.0.5, git-fmt-0.3.0.4, git-fmt-0.3.0.3, git-fmt-0.3.0.2, git-fmt-0.3.0.1, git-fmt-0.3.0.0, git-fmt-0.2.2.1, git-fmt-0.2.2.0, git-fmt-0.2.1.2, git-fmt-0.2.1.1 (constraint from user target requires ==0.2.1.0) trying: git-fmt-0.2.1.0 next goal: base (dependency of git-fmt-0.2.1.0) rejecting: base-4.9.0.0/installed-4.9... (conflict: git-fmt => base==4.8.*) rejecting: base-4.9.0.0, base-4.8.2.0, base-4.8.1.0, base-4.8.0.0, base-4.7.0.2, base-4.7.0.1, base-4.7.0.0, base-4.6.0.1, base-4.6.0.0, base-4.5.1.0, base-4.5.0.0, base-4.4.1.0, base-4.4.0.0, base-4.3.1.0, base-4.3.0.0, base-4.2.0.2, base-4.2.0.1, base-4.2.0.0, base-4.1.0.0, base-4.0.0.0, base-3.0.3.2, base-3.0.3.1 (constraint from non-upgradeable package requires installed instance) Dependency tree exhaustively searched.