diff --git a/int-multimap.cabal b/int-multimap.cabal
--- a/int-multimap.cabal
+++ b/int-multimap.cabal
@@ -1,7 +1,7 @@
 name:
   int-multimap
 version:
-  0.1.1
+  0.1.1.1
 synopsis:
   A data structure that associates each Int key with a set of values
 category:
diff --git a/library/IntMultiMap.hs b/library/IntMultiMap.hs
--- a/library/IntMultiMap.hs
+++ b/library/IntMultiMap.hs
@@ -33,6 +33,7 @@
 import qualified Data.HashSet as B
 import qualified Data.Foldable as C
 import qualified GHC.Exts as G
+import GHC.Generics
 import Prelude hiding (map, null)
 import Data.Int
 import Data.Hashable
@@ -45,7 +46,7 @@
 -}
 newtype IntMultiMap a =
   IntMultiMap (A.IntMap (B.HashSet a))
-  deriving(Foldable)
+  deriving(Foldable, Eq, Show, Generic)
 
 {--------------------------------------------------------------------
   Transformations