diff --git a/src/Weigh/GHCStats.hs b/src/Weigh/GHCStats.hs
--- a/src/Weigh/GHCStats.hs
+++ b/src/Weigh/GHCStats.hs
@@ -14,8 +14,12 @@
   ,maxBytesInUse)
   where
 
+#if __GLASGOW_HASKELL__ < 802
 import Data.Int
+#else
+import Data.Int
 import Data.Word
+#endif
 import GHC.Stats
 import System.Mem
 
@@ -59,14 +63,14 @@
 getGhcStatsSizeInBytes = do
   s1 <- oneGetStats
   s2 <- twoGetSTats
-  pure (fromIntegral (totalBytesAllocated s2 - totalBytesAllocated s1))
+  return (fromIntegral (totalBytesAllocated s2 - totalBytesAllocated s1))
   where
     oneGetStats = do
       performGC
       !s <- getStats
-      pure s
+      return s
     twoGetSTats = do
       performGC
       !_ <- getStats
       !s <- getStats
-      pure s
+      return s
diff --git a/weigh.cabal b/weigh.cabal
--- a/weigh.cabal
+++ b/weigh.cabal
@@ -1,5 +1,5 @@
 name:                weigh
-version:             0.0.6
+version:             0.0.7
 synopsis:            Measure allocations of a Haskell functions/values
 description:         Please see README.md
 homepage:            https://github.com/fpco/weigh#readme