haskell@gentoo.org Gentoo Haskell @base-orphans@ defines orphan instances that mimic instances available in later versions of @base@ to a wider (older) range of compilers. @base-orphans@ does not export anything except the orphan instances themselves and complements @<http://hackage.haskell.org/package/base-compat base-compat>@. See the README for what instances are covered: <https://github.com/haskell-compat/base-orphans#readme> haskell-compat/base-orphans#readme