Resolving dependencies... cabal: Could not resolve dependencies: trying: vinyl-operational-0.1.1 (user goal) trying: base-4.9.0.0/installed-4.9... (dependency of vinyl-operational-0.1.1) next goal: vinyl-plus (dependency of vinyl-operational-0.1.1) rejecting: vinyl-plus-0.1.1, vinyl-plus-0.1.0.0 (conflict: base==4.9.0.0/installed-4.9..., vinyl-plus => base>=4.8 && <4.9) Dependency tree exhaustively searched.