diff --git a/pipes-concurrency.cabal b/pipes-concurrency.cabal
--- a/pipes-concurrency.cabal
+++ b/pipes-concurrency.cabal
@@ -1,5 +1,5 @@
 Name: pipes-concurrency
-Version: 2.0.8
+Version: 2.0.9
 Cabal-Version: >=1.8.0.2
 Build-Type: Simple
 License: BSD3
@@ -32,7 +32,7 @@
     Hs-Source-Dirs: src
     Build-Depends:
         base          >= 4       && < 5  ,
-        async         >= 2.0.0.0 && < 2.2,
+        async         >= 2.0.0.0 && < 2.3,
         contravariant >= 1.3.3   && < 1.5,
         pipes         >= 4.0     && < 4.4,
         stm           >= 2.4.3   && < 2.5,
@@ -51,4 +51,4 @@
         pipes             >= 4.0.0 && < 4.4,
         pipes-concurrency                  ,
         stm               >= 2.4.3 && < 2.5,
-        async             >= 2.0   && < 2.2
+        async             >= 2.0   && < 2.3