Resolving dependencies... cabal: Could not resolve dependencies: next goal: eventloop (user goal) rejecting: eventloop-0.8.2.0, eventloop-0.8.1.2, eventloop-0.8.1.1, eventloop-0.8.1.0, eventloop-0.8.0.1, eventloop-0.8.0.0, eventloop-0.7.0.1, eventloop-0.7.0.0 (constraint from user target requires ==0.6.0.0) trying: eventloop-0.6.0.0 next goal: base (dependency of eventloop-0.6.0.0) rejecting: base-4.9.0.0/installed-4.9... (conflict: eventloop => base>=4.8 && <4.9) rejecting: 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) Dependency tree exhaustively searched.