diff --git a/src/Yam/Middleware/Auth.hs b/src/Yam/Middleware/Auth.hs
--- a/src/Yam/Middleware/Auth.hs
+++ b/src/Yam/Middleware/Auth.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP                  #-}
 module Yam.Middleware.Auth(
   -- * Auth Middleware
     authAppMiddleware
@@ -9,7 +10,12 @@
 import           Data.Swagger
 import qualified Data.Vault.Lazy                            as L
 import           Servant
+#if MIN_VERSION_servant_server(0,16,0)
+import           Servant.Server.Internal.Delayed
+import           Servant.Server.Internal.DelayedIO
+#else
 import           Servant.Server.Internal.RoutingApplication
+#endif
 import           Servant.Swagger
 import           Servant.Swagger.Internal
 import           System.IO.Unsafe                           (unsafePerformIO)
diff --git a/src/Yam/Types/Prelude.hs b/src/Yam/Types/Prelude.hs
--- a/src/Yam/Types/Prelude.hs
+++ b/src/Yam/Types/Prelude.hs
@@ -66,9 +66,15 @@
 import           Network.HTTP.Types
 import           Network.Wai
 import           Servant
-import           Servant.Server.Internal.ServantErr
 import           System.IO.Unsafe                   (unsafePerformIO)
 import           System.Random.MWC
+#if MIN_VERSION_servant_server(0,16,0)
+import           Servant.Server.Internal.ServerError
+type ServantErr = ServerError
+responseServantErr = responseServerError
+#else
+import           Servant.Server.Internal.ServantErr
+#endif
 
 type LogFunc = Loc -> LogSource -> LogLevel -> LogStr -> IO ()
 
diff --git a/yam.cabal b/yam.cabal
--- a/yam.cabal
+++ b/yam.cabal
@@ -1,6 +1,6 @@
 cabal-version: 1.12
 name: yam
-version: 0.5.13
+version: 0.5.14
 license: BSD3
 license-file: LICENSE
 copyright: (c) 2018 Daniel YU
@@ -66,8 +66,8 @@
         reflection >=2.1.4 && <2.2,
         salak >=0.1.8 && <0.3,
         scientific >=0.3.6.2 && <0.4,
-        servant-client ==0.15.*,
-        servant-server ==0.15.*,
+        servant-client >=0.15 && <0.17,
+        servant-server >=0.15 && <0.17,
         servant-swagger >=1.1.7 && <1.2,
         servant-swagger-ui >=0.3.2.3.19.3 && <0.4,
         swagger2 >=2.3.1 && <2.4,
@@ -135,8 +135,8 @@
         reflection >=2.1.4 && <2.2,
         salak >=0.1.8 && <0.3,
         scientific >=0.3.6.2 && <0.4,
-        servant-client ==0.15.*,
-        servant-server ==0.15.*,
+        servant-client >=0.15 && <0.17,
+        servant-server >=0.15 && <0.17,
         servant-swagger >=1.1.7 && <1.2,
         servant-swagger-ui >=0.3.2.3.19.3 && <0.4,
         swagger2 >=2.3.1 && <2.4,