diff --git a/src/Yam/Config.hs b/src/Yam/Config.hs
--- a/src/Yam/Config.hs
+++ b/src/Yam/Config.hs
@@ -4,6 +4,7 @@
   , defaultConfig
   ) where
 
+import           Control.Exception       (catch, throw)
 import           Data.Aeson
 import           Data.Foldable           (foldl')
 import qualified Data.HashMap.Strict     as H
@@ -14,10 +15,15 @@
 import           Data.Yaml
 import           System.Environment
 
+type Required = Bool
+
 class Config c where
   fetch   :: Text -> c -> Either String c
   merge   :: [c] -> c
   from    ::  (String, String)  -> c
+  merge'  :: [IO c] -> IO c
+  merge' c' = merge <$> sequence c'
+  fromFile :: FilePath -> Required -> IO c
   fromEnv :: [(String, String)] -> c
   fromEnv = merge . fmap from
   fromCommandLine :: [String]   -> c
@@ -25,7 +31,7 @@
     where
       select (k, '=':vs) = (k,vs)
       select v           = v
-  {-# MINIMAL fetch,merge,from #-}
+  {-# MINIMAL fetch,merge,from,fromFile #-}
 
 keys :: Text -> Text -> [Text]
 keys sep = dropWhile T.null . splitOn sep
@@ -34,7 +40,7 @@
 defaultConfig = do
   args <- getArgs
   envs <- getEnvironment
-  return $ merge $ [fromCommandLine args, fromEnv envs]
+  return $ merge [fromCommandLine args, fromEnv envs]
 
 instance Config Value where
   fetch key = go key (keys "." key)
@@ -44,11 +50,16 @@
         Nothing -> Left $ "Key " <> T.unpack k' <> " Not Found"
         Just v  -> go k' ks v
       go k' _              _  = Left $ "Key " <> T.unpack k' <> " Not Match"
-  merge = foldl' merge' Null
+  merge = foldl' merge2 Null
     where
-      merge' Null    a             = a
-      merge' (Object a) (Object b) = Object (H.unionWith merge' a b)
-      merge' a       _             = a
+      merge2 Null    a             = a
+      merge2 (Object a) (Object b) = Object (H.unionWith merge2 a b)
+      merge2 a       _             = a
+  fromFile f required = (decodeFileEither f >>= either throw return) `catch` go required
+    where
+      go :: Required -> ParseException -> IO Value
+      go False (InvalidYaml (Just (YamlException _))) = return Null
+      go _     e                                      = throw e
   from (k,v) = case Data.Yaml.decode $ cs v of
     Nothing -> Null
     Just a  -> go' (keys "_" $ T.toLower $ T.pack k) a
diff --git a/src/Yam/Config/Vault.hs b/src/Yam/Config/Vault.hs
new file mode 100644
--- /dev/null
+++ b/src/Yam/Config/Vault.hs
@@ -0,0 +1,64 @@
+module Yam.Config.Vault where
+
+import           Yam.Config
+
+import           Data.Default
+import           Data.Maybe      (fromMaybe)
+import           Data.Monoid
+import           Data.Text       (Text, justifyRight, pack)
+import           Data.Vault.Lazy
+import           Data.Word
+import           Numeric         (showHex)
+import           System.Random
+
+newtype Box a = Box (Maybe (Key a), Vault)
+
+instance Config (Box a) where
+  fetch _ = Right
+  merge = foldl1 $ \(Box (k, v)) (Box (_, v2)) -> Box (k, v `union` v2)
+  fromFile _ _ = error "Unsupported"
+  from _ = error "Unsupported"
+
+instance (Monad m) => HasValue m (Box v) v where
+  parse (Box (Just k, v)) = return $ case Data.Vault.Lazy.lookup k v of
+    Just  a -> Right a
+    Nothing -> Left  "Value Not Found"
+  parse _ = return $ Left "Key Not Exists"
+
+instance Default (Box a) where
+  def = Box (Nothing, empty)
+
+newBox :: Key a -> Vault -> Box a
+newBox k vault = Box (Just k, vault)
+
+emptyBox :: IO (Box a)
+emptyBox = do
+  k <- newKey
+  return $ Box (Just k, empty)
+
+toBox :: Box a -> Box b -> Box a
+toBox (Box (k, _)) (Box (_, v)) = Box (k,v)
+
+extracBox :: Box a -> Maybe a
+extracBox (Box (Just k, v)) = Data.Vault.Lazy.lookup k v
+extracBox _                 = Nothing
+
+extracBoxOrDefault :: a -> Box a -> a
+extracBoxOrDefault d b = fromMaybe d $ extracBox b
+
+randomString :: IO Text
+randomString = do
+  c <- randomIO :: IO Word64
+  return $ justifyRight 16 '0' $ pack $ showHex c ""
+
+addFirstVault :: (Monoid a, Eq a) => a -> a -> Key a -> Vault -> Vault
+addFirstVault prefix sep k v = insert k (go prefix sep (extracBox $ newBox k v)) v
+  where
+    go p s (Just n) = if n == mempty then p else p <> s <> n
+    go p _ _        = p
+
+addLastVault :: (Monoid a, Eq a) => a -> a -> Key a -> Vault -> Vault
+addLastVault prefix sep k v = insert k (go prefix sep (extracBox $ newBox k v)) v
+  where
+    go p s (Just n) = if n == mempty then p else n <> s <> p
+    go p _ _        = p
diff --git a/yam-config.cabal b/yam-config.cabal
--- a/yam-config.cabal
+++ b/yam-config.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 2978e60c94262fbb73adec86c8ec4866a254254ca9ea4efe720c6adbd9835cc9
+-- hash: 07e61434203150694307355b1fbe2416b9fc6dd94222ad72f329a68d1e444767
 
 name:           yam-config
-version:        0.3.1
+version:        0.3.2
 synopsis:       Yam Configuation
 description:    Configuation Loader Module for yam
 category:       Project
@@ -25,6 +25,7 @@
 library
   exposed-modules:
       Yam.Config
+      Yam.Config.Vault
   other-modules:
       Paths_yam_config
   hs-source-dirs:
@@ -34,8 +35,11 @@
   build-depends:
       aeson
     , base >=4.7 && <5
+    , data-default
+    , random
     , string-conversions
     , text
     , unordered-containers
+    , vault
     , yaml
   default-language: Haskell2010