diff --git a/enumset.cabal b/enumset.cabal
--- a/enumset.cabal
+++ b/enumset.cabal
@@ -1,5 +1,5 @@
 Name:             enumset
-Version:          0.1
+Version:          0.1.0.1
 License:          BSD3
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
@@ -25,7 +25,7 @@
 Build-Type:       Simple
 
 Source-Repository this
-  Tag:         0.1
+  Tag:         0.1.0.1
   Type:        darcs
   Location:    http://code.haskell.org/~thielema/enumset/
 
@@ -38,7 +38,7 @@
   Build-Depends:
     data-accessor >=0.2.1 && <0.3,
     storable-record >=0.0.1 && <0.1,
-    semigroups >=0.1 && <1.0,
+    semigroups >=0.1 && <1,
     base >=4 && <5
 
   GHC-Options:      -Wall
diff --git a/src/Data/EnumBitSet.hs b/src/Data/EnumBitSet.hs
--- a/src/Data/EnumBitSet.hs
+++ b/src/Data/EnumBitSet.hs
@@ -69,7 +69,7 @@
 -}
 instance (Enum a, Bits w) => Monoid (T w a) where
    mempty = empty
-   mappend = (.|.)
+   mappend = (<>)
 
 
 fromEnum :: (Enum a, Bits w) => a -> T w a