haskell-updater : Rebuild Haskell dependencies in Gentoo ( https://github.com/gentoo-haskell/haskell-updater#readme )
propellor : property-based host configuration management in haskell ( https://propellor.branchable.com/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a haskell
For Paludis use this rsync : rsync://gentoo.zugaina.org/haskell-portage
If you have a problem : ycarus(-at-)zugaina.org