diff --git a/Data/Git/Monad.hs b/Data/Git/Monad.hs
index 480af9f..27c3b3e 100644
--- a/Data/Git/Monad.hs
+++ b/Data/Git/Monad.hs
@@ -130 +130 @@ instance Resolvable Git.RefName where
-class (Functor m, Applicative m, Monad m) => GitMonad m where
+class (Functor m, Applicative m, Monad m, MonadFail m) => GitMonad m where
@@ -242,0 +243 @@ instance Monad GitM where
+instance MonadFail GitM where
@@ -315,0 +317 @@ instance Monad CommitAccessM where
+instance MonadFail CommitAccessM where
@@ -476,0 +479 @@ instance Monad CommitM where
+instance MonadFail CommitM where