diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,8 @@
+## 0.1.18
+
+- Fixing a buf of 0-RTT where unidirectionalStream waits for SH.
+- Introducing ccVersion to start with Version1.
+
 ## 0.1.17
 
 - Garding the new_connection_id attack.
diff --git a/Network/QUIC/Client/Run.hs b/Network/QUIC/Client/Run.hs
--- a/Network/QUIC/Client/Run.hs
+++ b/Network/QUIC/Client/Run.hs
@@ -45,8 +45,8 @@
         verInfo = case resumptionSession resInfo of
             Nothing
                 | resumptionToken resInfo == emptyToken ->
-                    let vers = ccVersions conf
-                        ver = head vers
+                    let ver = ccVersion conf
+                        vers = ccVersions conf
                      in VersionInfo ver vers
             _ -> let ver = resumptionVersion resInfo in VersionInfo ver [ver]
     ex <- E.try $ runClient conf client False verInfo
@@ -71,6 +71,10 @@
         setToken conn $ resumptionToken $ ccResumption conf
         handshaker <- handshakeClient conf' conn myAuthCIDs
         let client = do
+                -- For 0-RTT, the following variables should be initialized
+                -- in advance.
+                setTxMaxStreams conn $ initialMaxStreamsBidi defaultParameters
+                setTxUniMaxStreams conn $ initialMaxStreamsUni defaultParameters
                 if ccUse0RTT conf
                     then wait0RTTReady conn
                     else wait1RTTReady conn
diff --git a/Network/QUIC/Config.hs b/Network/QUIC/Config.hs
--- a/Network/QUIC/Config.hs
+++ b/Network/QUIC/Config.hs
@@ -46,8 +46,10 @@
 
 -- | Client configuration.
 data ClientConfig = ClientConfig
-    { ccVersions :: [Version]
-    -- ^ Compatible versions in the preferred order.
+    { ccVersion :: Version
+    -- ^ The version to start with.
+    , ccVersions :: [Version]
+    -- ^ Compatible versions with 'ccVersion' in the preferred order.
     , ccCiphers :: [Cipher]
     -- ^ Cipher candidates defined in TLS 1.3.
     , ccGroups :: [Group]
@@ -83,7 +85,8 @@
 defaultClientConfig :: ClientConfig
 defaultClientConfig =
     ClientConfig
-        { ccVersions = [Version2, Version1]
+        { ccVersion = Version1
+        , ccVersions = [Version2, Version1]
         , ccCiphers = supportedCiphers defaultSupported
         , ccGroups = supportedGroups defaultSupported
         , ccParameters = defaultParameters
diff --git a/Network/QUIC/Packet/Token.hs b/Network/QUIC/Packet/Token.hs
--- a/Network/QUIC/Packet/Token.hs
+++ b/Network/QUIC/Packet/Token.hs
@@ -30,8 +30,6 @@
     deriving (Generic)
 
 instance Serialise UnixTime
-instance Serialise Version
-instance Serialise CID
 instance Serialise CryptoToken
 
 isRetryToken :: CryptoToken -> Bool
diff --git a/Network/QUIC/Types/CID.hs b/Network/QUIC/Types/CID.hs
--- a/Network/QUIC/Types/CID.hs
+++ b/Network/QUIC/Types/CID.hs
@@ -17,7 +17,9 @@
 
 import qualified Data.ByteString.Short as Short
 
+import Codec.Serialise
 import GHC.Generics
+
 import Network.QUIC.Imports
 
 myCIDLength :: Int
@@ -25,6 +27,8 @@
 
 -- | A type for conneciton ID.
 newtype CID = CID Bytes deriving (Eq, Ord, Generic)
+
+instance Serialise CID
 
 instance Show CID where
     show (CID cid) = shortToString (enc16s cid)
diff --git a/Network/QUIC/Types/Packet.hs b/Network/QUIC/Types/Packet.hs
--- a/Network/QUIC/Types/Packet.hs
+++ b/Network/QUIC/Types/Packet.hs
@@ -4,6 +4,7 @@
 
 module Network.QUIC.Types.Packet where
 
+import Codec.Serialise
 import Data.Ix
 import GHC.Generics
 import Network.TLS.QUIC (ExtensionID (EID_QuicTransportParameters, ExtensionID))
@@ -20,6 +21,8 @@
 
 -- | QUIC version.
 newtype Version = Version Word32 deriving (Eq, Ord, Generic)
+
+instance Serialise Version
 
 {- FOURMOLU_DISABLE -}
 pattern Negotiation      :: Version
diff --git a/Network/QUIC/Types/Resumption.hs b/Network/QUIC/Types/Resumption.hs
--- a/Network/QUIC/Types/Resumption.hs
+++ b/Network/QUIC/Types/Resumption.hs
@@ -1,7 +1,10 @@
+{-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE RecordWildCards #-}
 
 module Network.QUIC.Types.Resumption where
 
+import Codec.Serialise
+import GHC.Generics
 import Network.TLS hiding (Version)
 import Network.TLS.QUIC
 
@@ -18,7 +21,9 @@
     , resumptionToken :: Token
     , resumptionRetry :: Bool
     }
-    deriving (Eq, Show)
+    deriving (Eq, Show, Generic)
+
+instance Serialise ResumptionInfo
 
 defaultResumptionInfo :: ResumptionInfo
 defaultResumptionInfo =
diff --git a/quic.cabal b/quic.cabal
--- a/quic.cabal
+++ b/quic.cabal
@@ -1,6 +1,6 @@
 cabal-version:      >=1.10
 name:               quic
-version:            0.1.17
+version:            0.1.18
 license:            BSD3
 license-file:       LICENSE
 maintainer:         kazu@iij.ad.jp
@@ -128,7 +128,7 @@
         base >=4.9 && <5,
         array >= 0.5 && < 0.6,
         base16-bytestring >= 1.0 && < 1.1,
-        bytestring >= 0.10 && < 0.13,
+        bytestring >= 0.10,
         containers >= 0.6 && < 0.7,
         crypto-token >= 0.1.1 && < 0.2,
         crypton >= 0.34 && < 0.35,
@@ -141,7 +141,7 @@
         fast-logger >= 3.2.2 && < 3.3,
         unix-time >= 0.4.12 && < 0.5,
         iproute >= 1.7.12 && < 1.8,
-        network >= 3.1.4 && < 3.2,
+        network >= 3.1.4,
         network-byte-order >= 0.1.7 && < 0.2,
         network-control >= 0.0.2 && < 0.1,
         network-udp >= 0.0.0 && < 0.1,