diff --git a/beamable.cabal b/beamable.cabal
--- a/beamable.cabal
+++ b/beamable.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.1.0.0
+version:             0.1.0.1
 
 -- A short (one-line) description of the package.
 synopsis:            Generic serializer/deserializer with compact representation
@@ -63,7 +63,7 @@
 
   -- Other library packages from which modules are imported.
   build-depends:
-    base >= 4.5 && < 4.7,
+    base >= 4.5 && < 4.8,
     blaze-builder >= 0.3,
     bytestring >= 0.9,
     ghc-prim,
@@ -77,11 +77,11 @@
   type:           exitcode-stdio-1.0
 
   build-depends:
-    test-framework             >= 0.4 && < 0.7,
-    test-framework-quickcheck2 >= 0.2 && < 0.3,
+    test-framework             >= 0.4 && < 0.9,
+    test-framework-quickcheck2 >= 0.2 && < 0.4,
     QuickCheck                 >= 2.4 && < 2.6,
     -- Copied from regular dependencies...
-    base >= 4.5 && < 4.7,
+    base >= 4.5 && < 4.8,
     blaze-builder >= 0.3,
     bytestring >= 0.9,
     ghc-prim,
diff --git a/src/Data/Beamable/Integer.hs b/src/Data/Beamable/Integer.hs
--- a/src/Data/Beamable/Integer.hs
+++ b/src/Data/Beamable/Integer.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE CPP #-}
 {-# LANGUAGE MagicHash #-}
 {-# LANGUAGE UnboxedTuples #-}
 module Data.Beamable.Integer
@@ -30,7 +31,7 @@
 
 unbeamInteger :: ByteString -> (Integer, ByteString)
 unbeamInteger bs
-    | baSize# <# 0# = (S# x#, bs'')
+    | primTrue (baSize# <# 0#) = (S# x#, bs'')
     | otherwise  = runSTRep $ \s# ->
         let (# s'#, mba# #)  = newByteArray# baSize# s#
             s''#             = go mba# 0# s'#
@@ -42,9 +43,19 @@
     !(I# x#, bs'')     = first fromIntegral $ unbeamInt bs'
 
     go mba# i# s#
-        | i# >=# baSize# = s#
+        | primTrue (i# >=# baSize#) = s#
         | otherwise      =
             let !(W8# b#) = B.index bs'' (I# i#)
                 s'#       = writeWord8Array# mba# i# b# s#
             in go mba# (i# +# 1#) s'#
 {-# INLINE unbeamInteger #-}
+
+#if MIN_VERSION_base(4,7,0)
+primTrue :: Int# -> Bool
+primTrue x = tagToEnum# x
+-- could use isTrue#, but that will introduce extraneous error
+-- checking that we don't need.
+#else
+primTrue :: Bool -> Bool
+primTrue = id
+#endif