@@ -390,6 +390,7 @@ defaultStablePackages ghcVer requireHP = unPackageMap $ execWriter $ do
390390
391391 -- https://github.com/fpco/stackage/issues/217
392392 addRange "Michael Snoyman" "transformers" "< 0.4"
393+ addRange "Michael Snoyman" "mtl" "< 2.2"
393394
394395 -- Requires too new a version of text
395396 when (ghcVer == GhcMajorVersion 7 4 && requireHP) $ do