diff --git a/data-ref.cabal b/data-ref.cabal
--- a/data-ref.cabal
+++ b/data-ref.cabal
@@ -1,6 +1,7 @@
+Cabal-Version:    2.2
 Name:             data-ref
-Version:          0.0.2
-License:          BSD3
+Version:          0.1
+License:          BSD-3-Clause
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
 Maintainer:       Henning Thielemann <haskell@henning-thielemann.de>
@@ -18,24 +19,24 @@
   .
   Similar packages: @reference@, @ref-mtl@, @ref-fd@, @ref-tf@.
 Tested-With:       GHC==7.4.2, GHC==8.0.1
-Cabal-Version:     >=1.6
 Build-Type:        Simple
 Source-Repository head
   type:     darcs
-  location: http://hub.darcs.net/thielema/data-ref/
+  location: https://hub.darcs.net/thielema/data-ref/
 
 Source-Repository this
   type:     darcs
-  location: http://hub.darcs.net/thielema/data-ref/
-  tag:      0.0.2
+  location: https://hub.darcs.net/thielema/data-ref/
+  tag:      0.1
 
 Library
   Build-Depends:
-    transformers >=0.4 && <0.6,
+    transformers >=0.4 && <0.7,
     data-accessor >=0.2.2 && <0.3,
     stm >=2.2 && <2.6,
     base >=2 && <5
 
+  Default-Language: Haskell98
   GHC-Options:      -Wall
   Hs-Source-Dirs:   src
   Exposed-Modules:
diff --git a/src/Data/Ref.hs b/src/Data/Ref.hs
--- a/src/Data/Ref.hs
+++ b/src/Data/Ref.hs
@@ -29,7 +29,6 @@
 import qualified Control.Monad.Trans.Writer.Lazy as MWL
 import qualified Control.Monad.Trans.Writer.Strict as MWS
 import qualified Control.Monad.Trans.Cont as MC
-import qualified Control.Monad.Trans.Error as ME
 import qualified Control.Monad.Trans.Except as MEx
 import qualified Control.Monad.Trans.Maybe as MM
 import qualified Control.Monad.Trans.Reader as MR
@@ -89,7 +88,6 @@
 instance C m => C (MI.IdentityT m) where new = newLifted
 
 instance C m => C (MM.MaybeT m) where new = newLifted
-instance (ME.Error e, C m) => C (ME.ErrorT e m) where new = newLifted
 instance (C m) => C (MEx.ExceptT e m) where new = newLifted
 
 instance C m => C (MC.ContT r m) where new = newLifted