diff --git a/System/Random/Mersenne/Pure64.hs b/System/Random/Mersenne/Pure64.hs
--- a/System/Random/Mersenne/Pure64.hs
+++ b/System/Random/Mersenne/Pure64.hs
@@ -56,6 +56,12 @@
 pureMT :: Word64 -> PureMT
 pureMT = mkPureMT . seedBlock . fromIntegral
 
+#if !MIN_VERSION_time(1,6,0)
+diffTimeToPicoseconds :: DiffTime -> Integer
+diffTimeToPicoseconds d =
+    round (1000 * 1000 * 1000 * 1000 * d)
+#endif
+
 -- | Create a new PureMT generator, using the clocktime as the base for the seed.
 newPureMT :: IO PureMT
 newPureMT = do
diff --git a/mersenne-random-pure64.cabal b/mersenne-random-pure64.cabal
--- a/mersenne-random-pure64.cabal
+++ b/mersenne-random-pure64.cabal
@@ -1,5 +1,5 @@
 name:            mersenne-random-pure64
-version:         0.2.1.0
+version:         0.2.2.0
 homepage:        http://code.haskell.org/~dons/code/mersenne-random-pure64/
 synopsis:        Generate high quality pseudorandom numbers purely using a Mersenne Twister
 description:
@@ -26,7 +26,7 @@
 maintainer:      Don Stewart <dons00@gmail.com>
 cabal-version:   >= 1.6.0
 build-type:      Simple
-tested-with:     GHC == 7.6.2, GHC == 7.7
+tested-with:     GHC == 7.6.2, GHC == 7.8.4, GHC == 7.10.3, GHC == 8.0.1
 
 source-repository head
   type: git