Resolving dependencies... cabal: Could not resolve dependencies: [__0] trying: poke-0.0.0.1 (user goal) [__1] next goal: text (dependency of poke) [__1] rejecting: text-1.2.3.2/installed-1.2.3.2 (conflict: poke => text>=1.2.4.0 && <1.2.5) [__1] trying: text-1.2.4.0 [__2] next goal: base (dependency of poke) [__2] rejecting: base-4.14.1.0/installed-4.14.1.0 (conflict: text => ghc-prim>=0.2 && <0.6, base => ghc-prim==0.6.1/installed-0.6.1) [__2] rejecting: base-4.14.0.0, base-4.13.0.0, 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) [__2] fail (backjumping, conflict set: base, poke, text) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: poke, text, base