diff --git a/pkgs/development/haskell-modules/configuration-common.nix b/pkgs/development/haskell-modules/configuration-common.nix
index 901c4d387661..06f1ecd5ed0c 100644
--- a/pkgs/development/haskell-modules/configuration-common.nix
+++ b/pkgs/development/haskell-modules/configuration-common.nix
@@ -720,6 +720,9 @@ self: super: {
     '';
   });
 
+  # A simple MonadFail patch would do too, but not doing the tests is easier
+  megaparsec_6_5_0 = dontCheck super.megaparsec_6_5_0;
+
   # The standard libraries are compiled separately
   idris = generateOptparseApplicativeCompletion "idris" (
     doJailbreak (dontCheck super.idris)