diff --git a/saltine.cabal b/saltine.cabal
--- a/saltine.cabal
+++ b/saltine.cabal
@@ -1,5 +1,5 @@
 name:                saltine
-version:             0.1.0.0
+version:             0.1.0.1
 synopsis:            Cryptography that's easy to digest (NaCl/libsodium bindings).
 description:
 
@@ -89,3 +89,4 @@
               , QuickCheck
               , test-framework-quickcheck2
               , test-framework
+              , semigroups
diff --git a/tests/Util.hs b/tests/Util.hs
--- a/tests/Util.hs
+++ b/tests/Util.hs
@@ -11,6 +11,7 @@
 import           Data.Monoid
 import           Data.Word (Word8)
 import           Data.Bits (xor)
+import           Data.Semigroup (Semigroup)
 import           Test.QuickCheck
 import           GHC.Exts (IsList(..))
 
@@ -30,7 +31,7 @@
         Just x  -> x
 
 newtype Perturb = Perturb [Word8]
-    deriving (Show,Monoid)
+    deriving (Show,Semigroup,Monoid)
 
 instance IsList Perturb where
     type Item Perturb = Word8