In order to address #3003 https://github.com/haskell/cabal/issues/3003 a new release of Cabal library has been made off of the 1.22, 1.20 and 1.18 branches. This is now available on hackage.haskell.org and the downloads page. The travis-ci tests for the 1.18 branch are currently failing as they are unable to contact the GCE ubuntu mirrors, once this is resolved and they pass I will close #3003. Further updates on this issue will be available there also. Cheers, Ryan