Resolving dependencies... Error: cabal: Could not resolve dependencies: [__0] next goal: pms-ui-notification (user goal) [__0] rejecting: pms-ui-notification-0.0.1.0 (unsupported spec-version 3.12) [__0] fail (backjumping, conflict set: pms-ui-notification) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: pms-ui-notification