diff --git a/utf8-string.cabal b/utf8-string.cabal
index a0b6d7e38a35fde2f341326dbcdfaf3877af0b26..87aaa8f5ff1aed427cc74ed8fdb003174f757e44 100644
--- a/utf8-string.cabal
+++ b/utf8-string.cabal
@@ -18,7 +18,7 @@ Extra-Source-Files: CHANGELOG.markdown
 library
   Ghc-options:        -W -O2
 
-  build-depends: base >= 4.3, bytestring >= 0.9
+  build-depends: base >= 4.3 && < 4.9, bytestring >= 0.9
 
   Extensions:         CPP
   Exposed-modules:    Codec.Binary.UTF8.String