Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: Spock-api-ghcjs-0.14.0.0 (user goal)
[__1] next goal: ghcjs-base (dependency of Spock-api-ghcjs)
[__1] rejecting: ghcjs-base-0.2.0.0 (conflict: requires JavaScriptFFI)
[__1] fail (backjumping, conflict set: Spock-api-ghcjs, ghcjs-base)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: Spock-api-ghcjs, ghcjs-base