diff --git a/Dangerous.cabal b/Dangerous.cabal
--- a/Dangerous.cabal
+++ b/Dangerous.cabal
@@ -1,5 +1,5 @@
 Name:          Dangerous
-Version:       0.3.0
+Version:       0.3.1
 License:       MIT
 License-file:  LICENSE
 Category:      Error Handling
@@ -20,6 +20,7 @@
 Library
     Hs-Source-Dirs:   src
     Build-Depends:    base >= 4 && < 5,
+                      MaybeT >= 0.1.2,
                       mtl >= 1.0
     Exposed-modules:  Control.Dangerous, Control.Dangerous.Extensions
     Ghc-Options:      -Wall