diff --git a/vault.cabal b/vault.cabal
--- a/vault.cabal
+++ b/vault.cabal
@@ -1,5 +1,5 @@
 Name:               vault
-Version:            0.2.0.0
+Version:            0.2.0.1
 Synopsis:           a persistent store for values of arbitrary types
 Description:
   A /vault/ is a persistent store for values of arbitrary types.
@@ -30,7 +30,7 @@
 
 Library
     hs-source-dirs:     src
-    build-depends:      base == 4.*, containers == 0.4.*
+    build-depends:      base == 4.*, containers >= 0.4 && < 0.6
     if impl(ghc)
         build-depends:  unordered-containers >= 0.2.1.0 && < 0.3,
                         hashable == 1.1.*