Resolving dependencies... cabal: Could not resolve dependencies: [__0] trying: spatial-rotations-0.1.0.1 (user goal) [__1] next goal: vector-space (dependency of spatial-rotations) [__1] rejecting: vector-space-0.14, vector-space-0.13 (conflict: spatial-rotations => vector-space>=0.12 && <0.13) [__1] trying: vector-space-0.12 [__2] next goal: base (dependency of spatial-rotations) [__2] rejecting: base-4.11.1.0/installed-4.1... (conflict: vector-space => base>=4.6 && <4.11) [__2] rejecting: base-4.12.0.0, base-4.11.1.0, base-4.11.0.0, base-4.10.1.0, base-4.10.0.0, base-4.9.1.0, 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) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: spatial-rotations, vector-space, base