diff --git a/nondeterminism.cabal b/nondeterminism.cabal
--- a/nondeterminism.cabal
+++ b/nondeterminism.cabal
@@ -1,5 +1,5 @@
 Name:                nondeterminism
-Version:             1.2
+Version:             1.4
 Description:         Nondeterministic computations
 License:             LGPL
 License-file:        LICENSE
@@ -7,7 +7,7 @@
 Maintainer:          Andrei Barbu <andrei@0xab.com>
 Category:            Control, AI, Constraints, Failure, Monads
 Build-Type:          Simple
-cabal-version:       >= 1.8
+cabal-version:       >= 1.10
 Synopsis:
     A monad and monad transformer for nondeterministic computations.
 extra-source-files:  README.md
@@ -21,9 +21,12 @@
   Exposed-modules:   Control.Monad.Amb
   Hs-Source-Dirs:    src
   ghc-options:       -Wall
+  default-extensions: CPP
+  default-language:    Haskell2010
 
 test-suite AmbTests
   type:           exitcode-stdio-1.0
   hs-source-dirs: tests
   main-is:        test.hs
   build-depends:  base >= 4 && < 5, tasty, tasty-hunit, nondeterminism
+  default-language:    Haskell2010
diff --git a/src/Control/Monad/Amb.hs b/src/Control/Monad/Amb.hs
--- a/src/Control/Monad/Amb.hs
+++ b/src/Control/Monad/Amb.hs
@@ -43,6 +43,9 @@
 import Control.Monad.State.Lazy
 import Control.Monad.Identity
 import Control.Applicative
+#if __GLASGOW_HASKELL__ < 709
+import Data.Monoid
+#endif
 
 -- $overview
 --