diff --git a/mustache2hs.cabal b/mustache2hs.cabal
--- a/mustache2hs.cabal
+++ b/mustache2hs.cabal
@@ -1,5 +1,5 @@
 name:            mustache2hs
-version:         0.2.1
+version:         0.2.1.1
 cabal-version:   >= 1.8
 license:         OtherLicense
 license-file:    COPYING
@@ -39,13 +39,13 @@
         other-modules: ParseRecords
 
         build-depends:
-                base == 4.*,
+                base >= 4.2.0.0 && < 5.0.0.0,
                 text,
                 parsec >= 3.1.2,
                 haskell-src,
                 utf8-string,
                 bytestring,
-                blaze-builder,
+                blaze-builder >= 0.2.0.0,
                 transformers,
                 filepath
 
diff --git a/mustache2hs.hs b/mustache2hs.hs
--- a/mustache2hs.hs
+++ b/mustache2hs.hs
@@ -10,7 +10,7 @@
 import Data.Char
 import Data.Word
 import Data.List
-import Control.Monad
+import Control.Monad (when, join)
 import Control.Arrow
 import Control.Monad.Trans.Class (lift)
 import Control.Monad.Trans.State (get, modify, evalState, State, StateT, evalStateT)
@@ -30,6 +30,10 @@
 import qualified Data.ByteString.UTF8 as BS
 
 import ParseRecords
+
+-- | Available as of base-4.3.0.0 in Control.Monad
+void :: Functor f => f a -> f ()
+void = fmap (const ())
 
 data Flag = Help | RecordModule String deriving (Show, Read, Eq)