diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,8 +1,17 @@
 # ChangeLog / ReleaseNotes
 
 
+## Version 0.1.0.1
+
+* Bugfix release.
+* Bugfix: Unable to compile with transformers >= 0.4.
+* Uploaded to [Hackage][]:
+  <http://hackage.haskell.org/package/endo-0.1.0.1>
+
+
 ## Version 0.1.0.0
 
+* **This version doesn't work with transformers >= 0.4.**
 * First public release.
 * Uploaded to [Hackage][]:
   <http://hackage.haskell.org/package/endo-0.1.0.0>
diff --git a/endo.cabal b/endo.cabal
--- a/endo.cabal
+++ b/endo.cabal
@@ -1,5 +1,5 @@
 name:                   endo
-version:                0.1.0.0
+version:                0.1.0.1
 synopsis:               Endomorphism utilities.
 description:
   Package defines extra functions for 'Data.Monoid.Endo' data type, and also
@@ -113,4 +113,4 @@
 source-repository this
   type:                 git
   location:             git://github.com/trskop/endo.git
-  tag:                  0.1.0.0
+  tag:                  0.1.0.1
diff --git a/src/Data/Monoid/Endo/Fold.hs b/src/Data/Monoid/Endo/Fold.hs
--- a/src/Data/Monoid/Endo/Fold.hs
+++ b/src/Data/Monoid/Endo/Fold.hs
@@ -70,7 +70,7 @@
 import Data.Typeable (Typeable)
 #endif
 
-#if HAVE_EXCEPTT
+#ifdef HAVE_EXCEPTT
 import Control.Monad.Trans.Except (ExceptT)
 #endif
 import Control.Monad.Trans.Identity (IdentityT)
@@ -217,8 +217,15 @@
     foldEndoArgs     = pure . foldEndoArgs
     dualFoldEndoArgs = pure . dualFoldEndoArgs
 
-#if HAVE_EXCEPTT
-instance (Applicative f, FoldEndoArgs r) => FoldEndoArgs (ExceptT e f r) where
+#ifdef HAVE_EXCEPTT
+instance
+    ( Monad m
+#ifndef APPLICATIVE_MONAD
+    , Functor m
+#endif
+    , FoldEndoArgs r
+    ) => FoldEndoArgs (ExceptT e m r)
+  where
     type ResultOperatesOn (ExceptT e f r) = ResultOperatesOn r
     foldEndoArgs     = pure . foldEndoArgs
     dualFoldEndoArgs = pure . dualFoldEndoArgs