For people like me who would like to try out 7.8.2, but don't want to make new creative ways of making your system be able to handle multiple ghc/cabal/etc, I created a docker image. Source code, instructions how to build image yourself, or just pull/run it are here: https://bitbucket.org/k_bx/docker-ghc-7.8 Thanks. // I will make a github mirror once hg-git is fixed back by new dulwich lib release soon