diff --git a/Network/Mail/Mime/SES.hs b/Network/Mail/Mime/SES.hs
--- a/Network/Mail/Mime/SES.hs
+++ b/Network/Mail/Mime/SES.hs
@@ -42,6 +42,7 @@
     , sesSecretKey :: ByteString
     , sesRegion    :: Text
     }
+  deriving Show
 
 renderSendMailSES :: MonadIO m => Manager -> SES -> Mail -> m ()
 renderSendMailSES m ses mail = liftIO (renderMail' mail) >>= sendMailSES m ses
diff --git a/mime-mail-ses.cabal b/mime-mail-ses.cabal
--- a/mime-mail-ses.cabal
+++ b/mime-mail-ses.cabal
@@ -1,5 +1,5 @@
 Name:                mime-mail-ses
-Version:             0.3.0
+Version:             0.3.1
 Synopsis:            Send mime-mail messages via Amazon SES
 Homepage:            http://github.com/snoyberg/mime-mail
 License:             MIT