diff --git a/Text/Blaze/Internal.hs b/Text/Blaze/Internal.hs
--- a/Text/Blaze/Internal.hs
+++ b/Text/Blaze/Internal.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE OverloadedStrings, GeneralizedNewtypeDeriving, Rank2Types,
-             FlexibleInstances, ExistentialQuantification #-}
+             FlexibleInstances, ExistentialQuantification, DeriveDataTypeable #-}
 -- | The BlazeHtml core, consisting of functions that offer the power to
 -- generate custom HTML elements. It also offers user-centric functions, which
 -- are exposed through 'Text.Blaze'.
@@ -63,6 +63,7 @@
 import qualified Data.Text.Encoding as T
 import qualified Data.Text.Lazy as LT
 import GHC.Exts (IsString (..))
+import Data.Typeable (Typeable)
 
 -- | A static string that supports efficient output to all possible backends.
 --
@@ -127,6 +128,7 @@
     | AddCustomAttribute ChoiceString ChoiceString ChoiceString (HtmlM a)
     -- | Empty HTML.
     | Empty
+    deriving (Typeable)
 
 -- | Simplification of the 'HtmlM' datatype.
 --
diff --git a/blaze-html.cabal b/blaze-html.cabal
--- a/blaze-html.cabal
+++ b/blaze-html.cabal
@@ -7,7 +7,7 @@
 -- The package version. See the Haskell package versioning policy
 -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for
 -- standards guiding when and how versions should be incremented.
-Version:             0.3.2.0
+Version:             0.3.2.1
 
 -- A short (one-line) description of the package.
 Synopsis:            A blazingly fast HTML combinator library.