Resolving dependencies... cabal: Could not resolve dependencies: next goal: machines (user goal) rejecting: machines-0.5.1, 0.4.1, 0.4.0.1, 0.4, 0.2.5, 0.2.4, 0.2.3.1, 0.2.3, 0.2.2, 0.2.1.3, 0.2.1.2, 0.2.1.1, 0.2.1, 0.1.2, 0.1.1 (global constraint requires ==0.1) trying: machines-0.1 next goal: base (dependency of machines-0.1) rejecting: base-4.8.1.0/installed-4f7... (conflict: machines => base<0) 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.