diff --git a/snap-core.cabal b/snap-core.cabal
--- a/snap-core.cabal
+++ b/snap-core.cabal
@@ -1,5 +1,5 @@
 name:           snap-core
-version:        0.5.1.3
+version:        0.5.1.4
 synopsis:       Snap: A Haskell Web Framework (Core)
 
 description:
@@ -127,7 +127,7 @@
 
 
   build-depends:
-    attoparsec >= 0.8.0.2 && < 0.9,
+    attoparsec >= 0.8.0.2 && < 0.10,
     attoparsec-enumerator >= 0.2.0.3,
     base >= 4 && < 5,
     blaze-builder >= 0.2.1.4 && <0.4,
diff --git a/test/snap-core-testsuite.cabal b/test/snap-core-testsuite.cabal
--- a/test/snap-core-testsuite.cabal
+++ b/test/snap-core-testsuite.cabal
@@ -21,7 +21,7 @@
 
   build-depends:
     QuickCheck >= 2.3.0.2,
-    attoparsec >= 0.8.1 && < 0.9,
+    attoparsec >= 0.8.1 && < 0.10,
     attoparsec-enumerator >= 0.2.0.3,
     base >= 4 && < 5,
     base16-bytestring == 0.1.*,