diff --git a/ghc-hedgehog.spec b/ghc-hedgehog.spec
index 9617df0..acae0a7 100644
--- a/ghc-hedgehog.spec
+++ b/ghc-hedgehog.spec
@@ -77,6 +77,7 @@ This package provides the Haskell %{pkg_name} library development files.
 
 %prep
 %autosetup -n %{pkg_name}-%{version}
+cabal-tweak-dep-ver mmorph '< 1.2' '< 1.3'
 
 %build
 %ghc_lib_build