--- a/irc-core.cabal
+++ b/irc-core.cabal
@@ -33,7 +33,7 @@
                        Irc.UserInfo
   other-modules:       View
 
-  build-depends:       base       >=4.9  && <4.11,
+  build-depends:       base       >=4.9  && <5,
                        base64-bytestring >= 1.0.0.1 && <1.1,
                        attoparsec >=0.13 && <0.14,
                        bytestring >=0.10 && <0.11,
