Resolving dependencies... cabal: Could not resolve dependencies: next goal: LambdaShell (user goal) rejecting: LambdaShell-0.9.3 (global constraint requires ==0.9.1) trying: LambdaShell-0.9.1 trying: base-4.8.1.0/installed-4f7... (dependency of LambdaShell-0.9.1) trying: Shellac-0.9.5.2 (dependency of LambdaShell-0.9.1) trying: directory-1.2.2.0/installed-258... (dependency of Shellac-0.9.5.2) next goal: haskell98 (dependency of LambdaShell-0.9.1) rejecting: haskell98-2.0.0.3 (conflict: base==4.8.1.0/installed-4f7..., haskell98 => base>=4.7 && <4.8) rejecting: haskell98-2.0.0.2 (conflict: base==4.8.1.0/installed-4f7..., haskell98 => base==4.6.*) rejecting: haskell98-2.0.0.1, 2.0.0.0 (conflict: directory==1.2.2.0/installed-258..., haskell98 => directory>=1.1 && <1.2) rejecting: haskell98-1.1.0.1, 1.1.0.0, 1.0.1.1 (conflict: base==4.8.1.0/installed-4f7..., haskell98 => base>=3 && <4.6) rejecting: haskell98-1.0.1.0 (conflict: base==4.8.1.0/installed-4f7..., haskell98 => base<4.6) rejecting: haskell98-1.0 (conflict: base==4.8.1.0/installed-4f7..., haskell98 => base<4.3) Dependency tree exhaustively searched.