Resolving dependencies... cabal: Could not resolve dependencies: next goal: bio (user goal) rejecting: bio-0.5.3, 0.5.2, 0.5.1, 0.5.0.1, 0.5, 0.4.8, 0.4.7, 0.4.6, 0.4.5, 0.4.4, 0.4, 0.3.5, 0.3.3.4, 0.3.3.2 (global constraint requires ==0.3.3.1) trying: bio-0.3.3.1 trying: base-4.8.1.0/installed-4f7... (dependency of bio-0.3.3.1) next goal: QuickCheck (dependency of bio-0.3.3.1) rejecting: QuickCheck-2.8.1, 2.8, 2.7.6, 2.7.5, 2.7.4, 2.7.3, 2.7.2, 2.7.1, 2.7, 2.6, 2.5.1.1, 2.5.1, 2.5, 2.4.2, 2.4.1.1, 2.4.1, 2.4.0.1, 2.4, 2.3.0.2, 2.3.0.1, 2.3, 2.2, 2.1.2, 2.1.1.1, 2.1.1, 2.1.0.3, 2.1.0.2, 2.1.0.1, 2.1 (conflict: bio => QuickCheck<2) trying: QuickCheck-1.2.0.1 rejecting: QuickCheck-1.2.0.1:+base3 (conflict: base==4.8.1.0/installed-4f7..., QuickCheck-1.2.0.1:base3 => base>=3 && <4) trying: QuickCheck-1.2.0.1:-base3 rejecting: QuickCheck-1.2.0.1:+base4 (conflict: base==4.8.1.0/installed-4f7..., QuickCheck-1.2.0.1:base4 => base>=4 && <4.8) rejecting: QuickCheck-1.2.0.1:-base4 (conflict: base==4.8.1.0/installed-4f7..., QuickCheck-1.2.0.1:base4 => base<3) Dependency tree exhaustively searched.