Resolving dependencies... cabal: Could not resolve dependencies: trying: concrete-haskell-0.1.0.9 (user goal) trying: vector-0.12.0.1 (dependency of concrete-haskell-0.1.0.9) next goal: thrift (dependency of concrete-haskell-0.1.0.9) rejecting: thrift-0.10.0 (conflict: vector==0.12.0.1, thrift => vector==0.10.12.2) rejecting: thrift-0.9.3, thrift-0.9.2, thrift-0.6.0 (conflict: concrete-haskell => thrift==0.10.0) Backjump limit reached (currently 2000, change with --max-backjumps or try to run with --reorder-goals).