Compatibility packages in 2026

Posted on 2026-05-07 by Oleg Grenrus engineering Seven years ago I wrote a post about compatibility packages. It is now highly outdated, so let us revisit the matter. Recently there have been a small push towards reinstallable base . While it's still far from being a thing, it made me remember that using impl(ghc >= 7.9) -like conditionals to guard against different base versions is semantically…