Resolving dependencies... cabal: Could not resolve dependencies: next goal: derive-trie (user goal) rejecting: derive-trie-0.2.1, derive-trie-0.2 (constraint from user target requires ==0.1.0) trying: derive-trie-0.1.0 trying: base-4.9.0.0/installed-4.9... (dependency of derive-trie-0.1.0) next goal: template-haskell (dependency of derive-trie-0.1.0) rejecting: template-haskell-2.11.0.0/installed-2.1..., template-haskell-2.11.0.0, template-haskell-2.10.0.0, template-haskell-2.9.0.0, template-haskell-2.8.0.0, template-haskell-2.7.0.0, template-haskell-2.6.0.0, template-haskell-2.5.0.0 (conflict: derive-trie => template-haskell==2.4.*) rejecting: template-haskell-2.4.0.1 (conflict: base==4.9.0.0/installed-4.9..., template-haskell => base==4.2.*) rejecting: template-haskell-2.4.0.0 (conflict: base==4.9.0.0/installed-4.9..., template-haskell => base>=3 && <4.3) rejecting: template-haskell-2.3.0.1, template-haskell-2.3.0.0, template-haskell-2.2.0.0 (conflict: derive-trie => template-haskell==2.4.*) Dependency tree exhaustively searched.