-
Use official bindists, except for Debian 9/Stretch http://downloads.haskell.org/debian/ is used. (There are no recent GHC/cabal-install for Debian 8/Jessie there) Use v2-update/v2-install to install Haskell tools. Try to unify structure of the different Dockerfiles, including installing GHC in one step (this will prevent sublayers from existing, making final image slightly smaller)
9103ff17