Resolving dependencies... cabal: Could not resolve dependencies: [__0] next goal: viewprof (user goal) [__0] rejecting: viewprof-0.0.0.33, viewprof-0.0.0.32, viewprof-0.0.0.31, viewprof-0.0.0.30, viewprof-0.0.0.29, viewprof-0.0.0.28, viewprof-0.0.0.27, viewprof-0.0.0.26, viewprof-0.0.0.25, viewprof-0.0.0.24, viewprof-0.0.0.23, viewprof-0.0.0.22, viewprof-0.0.0.21, viewprof-0.0.0.20, viewprof-0.0.0.19, viewprof-0.0.0.18, viewprof-0.0.0.17 (constraint from user target requires ==0.0.0.16) [__0] trying: viewprof-0.0.0.16 [__1] next goal: base (dependency of viewprof) [__1] rejecting: base-4.14.1.0/installed-4.14.1.0 (conflict: viewprof => base>=4.9 && <4.12) [__1] skipping: base-4.15.0.0, base-4.14.1.0, base-4.14.0.0, base-4.13.0.0, base-4.12.0.0 (has the same characteristics that caused the previous version to fail: excluded by constraint '>=4.9 && <4.12' from 'viewprof') [__1] rejecting: 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) [__1] fail (backjumping, conflict set: base, viewprof) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: base, viewprof