diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,7 @@
+1.5.5 [2021.07.27]
+------------------
+* Fix the build on old GHCs using `transformers-0.6.*`.
+
 1.5.4 [2021.07.25]
 ------------------
 * Allow building with `transformers-0.6.*`.
diff --git a/contravariant.cabal b/contravariant.cabal
--- a/contravariant.cabal
+++ b/contravariant.cabal
@@ -1,6 +1,6 @@
 name:          contravariant
 category:      Control, Data
-version:       1.5.4
+version:       1.5.5
 license:       BSD3
 cabal-version: >= 1.10
 license-file:  LICENSE
diff --git a/old-src/Data/Functor/Contravariant.hs b/old-src/Data/Functor/Contravariant.hs
--- a/old-src/Data/Functor/Contravariant.hs
+++ b/old-src/Data/Functor/Contravariant.hs
@@ -20,7 +20,9 @@
 {-# LANGUAGE Trustworthy #-}
 #endif
 
+#if !(MIN_VERSION_transformers(0,6,0))
 {-# OPTIONS_GHC -fno-warn-deprecations #-}
+#endif
 
 -----------------------------------------------------------------------------
 -- |
@@ -66,10 +68,8 @@
 
 import Control.Category
 
-import Control.Monad.Trans.Error
 import Control.Monad.Trans.Except
 import Control.Monad.Trans.Identity
-import Control.Monad.Trans.List
 import Control.Monad.Trans.Maybe
 import qualified Control.Monad.Trans.RWS.Lazy as Lazy
 import qualified Control.Monad.Trans.RWS.Strict as Strict
@@ -87,6 +87,11 @@
 import Data.Functor.Compose
 import Data.Functor.Reverse
 
+#if !(MIN_VERSION_transformers(0,6,0))
+import Control.Monad.Trans.Error
+import Control.Monad.Trans.List
+#endif
+
 #if MIN_VERSION_base(4,8,0)
 import Data.Monoid (Alt(..))
 #else
@@ -222,18 +227,12 @@
   contramap f (R1 ys) = R1 (contramap f ys)
 #endif
 
-instance Contravariant m => Contravariant (ErrorT e m) where
-  contramap f = ErrorT . contramap (fmap f) . runErrorT
-
 instance Contravariant m => Contravariant (ExceptT e m) where
   contramap f = ExceptT . contramap (fmap f) . runExceptT
 
 instance Contravariant f => Contravariant (IdentityT f) where
   contramap f = IdentityT . contramap f . runIdentityT
 
-instance Contravariant m => Contravariant (ListT m) where
-  contramap f = ListT . contramap (fmap f) . runListT
-
 instance Contravariant m => Contravariant (MaybeT m) where
   contramap f = MaybeT . contramap (fmap f) . runMaybeT
 
@@ -286,6 +285,14 @@
 instance Contravariant f => Contravariant (Reverse f) where
   contramap f = Reverse . contramap f . getReverse
   {-# INLINE contramap #-}
+
+#if !(MIN_VERSION_transformers(0,6,0))
+instance Contravariant m => Contravariant (ErrorT e m) where
+  contramap f = ErrorT . contramap (fmap f) . runErrorT
+
+instance Contravariant m => Contravariant (ListT m) where
+  contramap f = ListT . contramap (fmap f) . runListT
+#endif
 
 #ifdef MIN_VERSION_StateVar
 instance Contravariant SettableStateVar where