diff --git a/Yesod/Auth/HashDB.hs b/Yesod/Auth/HashDB.hs
--- a/Yesod/Auth/HashDB.hs
+++ b/Yesod/Auth/HashDB.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveDataTypeable         #-}
 {-# LANGUAGE QuasiQuotes                #-}
 {-# LANGUAGE ConstraintKinds            #-}
 {-# LANGUAGE FlexibleContexts           #-}
@@ -82,6 +83,7 @@
 
 import Control.Applicative         ((<$>), (<*>))
 import Control.Monad               (replicateM,liftM)
+import Data.Typeable
 
 import qualified Data.ByteString.Lazy.Char8 as BS (pack)
 import Data.Digest.Pure.SHA        (sha1, showDigest)
@@ -258,6 +260,7 @@
     password Text
     salt     Text
     UniqueUser username
+    deriving Typeable
 |]
 
 instance HashDBUser (UserGeneric backend) where
diff --git a/yesod-auth.cabal b/yesod-auth.cabal
--- a/yesod-auth.cabal
+++ b/yesod-auth.cabal
@@ -1,5 +1,5 @@
 name:            yesod-auth
-version:         1.2.5.0
+version:         1.2.5.1
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman, Patrick Brisbin