diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+## 1.4.16
+
+* Fix email provider [#1330](https://github.com/yesodweb/yesod/issues/1330)
+
 ## 1.4.15
 
 * Add JSON endpoints to Yesod.Auth.Email module
diff --git a/Yesod/Auth/Email.hs b/Yesod/Auth/Email.hs
--- a/Yesod/Auth/Email.hs
+++ b/Yesod/Auth/Email.hs
@@ -28,6 +28,60 @@
 --     * logout and sign in
 --     * reset their password
 --
+-- = Using JSON Endpoints
+--
+-- We are assuming that you have declared auth route as follows
+-- 
+-- @
+--    /auth AuthR Auth getAuth
+-- @
+-- 
+-- If you are using a different route, then you have to adjust the
+-- endpoints accordingly.
+--
+--     * Registration
+-- 
+-- @
+--       Endpoint: \/auth\/page\/email\/register
+--       Method: POST
+--       JSON Data: { "email": "myemail@domain.com" }
+-- @
+-- 
+--     * Forgot password
+--  
+-- @
+--       Endpoint: \/auth\/page\/email\/forgot-password
+--       Method: POST
+--       JSON Data: { "email": "myemail@domain.com" }
+-- @
+--
+--     * Login
+--  
+-- @
+--       Endpoint: \/auth\/page\/email\/login
+--       Method: POST
+--       JSON Data: { 
+--                      "email": "myemail@domain.com",
+--                      "password": "myStrongPassword"
+--                  }
+-- @
+-- 
+--     * Set new password
+--
+-- @
+--       Endpoint: \/auth\/page\/email\/set-password
+--       Method: POST
+--       JSON Data: {
+--                       "new": "newPassword",
+--                       "confirm": "newPassword",
+--                       "current": "currentPassword"
+--                  }
+-- @
+--
+--  Note that in the set password endpoint, the presence of the key
+--  "current" is dependent on how the 'needOldPassword' is defined in
+--  the instance for 'YesodAuthEmail'.
+
 module Yesod.Auth.Email
     ( -- * Plugin
       authEmail
@@ -184,7 +238,7 @@
     -- | Generate a random alphanumeric string.
     --
     -- @since 1.1.0
-    randomKey :: site -> IO Text
+    randomKey :: site -> IO VerKey
     randomKey _ = Nonce.nonce128urlT defaultNonceGen
 
     -- | Route to send user to after password has been set correctly.
@@ -401,12 +455,11 @@
     pidentifier <- lookupPostParam "email"
     midentifier <- case pidentifier of
                      Nothing -> do
-                       (jidentifier :: Result Value) <- lift parseJsonBody                                     
+                       (jidentifier :: Result Value) <- lift parseCheckJsonBody
                        case jidentifier of
                          Error _ -> return Nothing
                          Success val -> return $ parseMaybe parseEmail val
                      Just _ -> return pidentifier
-                                  
     let eidentifier = case midentifier of
                           Nothing -> Left Msg.NoIdentifierProvided
                           Just x
@@ -532,15 +585,15 @@
     result <- lift $ runInputPostResult $ (,)
         <$> ireq textField "email"
         <*> ireq textField "password"
-    
+
     midentifier <- case result of
                      FormSuccess (iden, pass) -> return $ Just (iden, pass)
                      _ -> do
-                       (creds :: Result Value) <- lift parseJsonBody
+                       (creds :: Result Value) <- lift parseCheckJsonBody
                        case creds of
                          Error _ -> return Nothing
                          Success val -> return $ parseMaybe parseCreds val
-                                              
+
     case midentifier of
       Nothing -> loginErrorMessageI LoginR Msg.NoIdentifierProvided
       Just (identifier, pass) -> do
@@ -665,7 +718,7 @@
 postPasswordR :: YesodAuthEmail master => HandlerT Auth (HandlerT master IO) TypedContent
 postPasswordR = do
     maid <- lift maybeAuthId
-    (creds :: Result Value) <- lift parseJsonBody
+    (creds :: Result Value) <- lift parseCheckJsonBody
     let jcreds = case creds of
                    Error _ -> Nothing
                    Success val -> parseMaybe parsePassword val
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:         1.4.15
+version:         1.4.16
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman, Patrick Brisbin
@@ -23,7 +23,7 @@
     build-depends:   base                    >= 4         && < 5
                    , authenticate            >= 1.3
                    , bytestring              >= 0.9.1.4
-                   , yesod-core              >= 1.4.20    && < 1.5
+                   , yesod-core              >= 1.4.31    && < 1.5
                    , wai                     >= 1.4
                    , template-haskell
                    , base16-bytestring