diff --git a/ChangeLog.md b/ChangeLog.md
new file mode 100644
--- /dev/null
+++ b/ChangeLog.md
@@ -0,0 +1,8 @@
+## 0.0.1
+
+- Making Haskell servers friendly with Chrome
+  [#20](https://github.com/kazu-yamamoto/quic/pull/20)
+
+## 0.0.0
+
+- Initial version.
diff --git a/Network/QUIC/Client.hs b/Network/QUIC/Client.hs
--- a/Network/QUIC/Client.hs
+++ b/Network/QUIC/Client.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE PatternSynonyms #-}
-
 -- | This main module provides APIs for QUIC clients.
 --   When a new better network interface is up,
 --   migration is done automatically.
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
@@ -1,6 +1,5 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE PatternGuards #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
 module Network.QUIC.Client.Run (
diff --git a/Network/QUIC/Closer.hs b/Network/QUIC/Closer.hs
--- a/Network/QUIC/Closer.hs
+++ b/Network/QUIC/Closer.hs
@@ -93,7 +93,7 @@
     loop n = do
         _ <- send
         getTimeMicrosecond >>= skip (Microseconds pto)
-        mx <- timeout (Microseconds (pto .>>. 1)) $ recv
+        mx <- timeout (Microseconds (pto .>>. 1)) recv
         case mx of
           Nothing -> hook
           Just 0  -> return ()
diff --git a/Network/QUIC/Connection.hs b/Network/QUIC/Connection.hs
--- a/Network/QUIC/Connection.hs
+++ b/Network/QUIC/Connection.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE OverloadedStrings #-}
-
 module Network.QUIC.Connection (
     module Network.QUIC.Connection.PacketNumber
   , module Network.QUIC.Connection.Crypto
diff --git a/Network/QUIC/Connection/Migration.hs b/Network/QUIC/Connection/Migration.hs
--- a/Network/QUIC/Connection/Migration.hs
+++ b/Network/QUIC/Connection/Migration.hs
@@ -157,7 +157,7 @@
     -- But receiver guarantees that there is at least one cidinfo.
     usedCIDInfo' | cidInfoSeq usedCIDInfo >= n = usedCIDInfo
                  | otherwise            = snd $ IntMap.findMin cidInfos'
-    revInfos' = foldr (\k m -> Map.delete k m) revInfos dropCIDs
+    revInfos' = foldr Map.delete revInfos dropCIDs
     db' = db {
         usedCIDInfo = usedCIDInfo'
       , cidInfos    = cidInfos'
diff --git a/Network/QUIC/Connection/Misc.hs b/Network/QUIC/Connection/Misc.hs
--- a/Network/QUIC/Connection/Misc.hs
+++ b/Network/QUIC/Connection/Misc.hs
@@ -59,7 +59,7 @@
     \ss@(s0:_) -> (s1:ss,s0)
 
 clearSockets :: Connection -> IO [Socket]
-clearSockets Connection{..} = atomicModifyIORef sockets $ \ss -> ([],ss)
+clearSockets Connection{..} = atomicModifyIORef sockets ([],)
 
 ----------------------------------------------------------------
 
@@ -141,7 +141,7 @@
     writeIORef tmouter (deRefWeak wtid >>= mapM_ killThread)
 
 replaceKillTimeouter :: Connection -> IO (IO ())
-replaceKillTimeouter Connection{..} = atomicModifyIORef' tmouter $ \m -> (return (), m)
+replaceKillTimeouter Connection{..} = atomicModifyIORef' tmouter (return (),)
 
 ----------------------------------------------------------------
 
diff --git a/Network/QUIC/Packet/Frame.hs b/Network/QUIC/Packet/Frame.hs
--- a/Network/QUIC/Packet/Frame.hs
+++ b/Network/QUIC/Packet/Frame.hs
@@ -196,27 +196,30 @@
 
 countZero :: Ptr Word8 -> Ptr Word8 -> IO Int
 countZero beg0 end0
-  | (end0 `minusPtr` beg0) <= ali = countBy1 beg0 end0 0
+  | (end0 `minusPtr` beg0) <= ali = fst <$> countBy1 beg0 end0 0
   | otherwise = do
     let beg1 = alignPtr beg0 ali
         end1' = alignPtr end0 ali
         end1 | end0 == end1' = end1'
              | otherwise     = end1' `plusPtr` negate ali
-    n1        <- countBy1 beg0 beg1 0
-    (n2,beg2) <- countBy8 (castPtr beg1) (castPtr end1) 0
-    n3        <- countBy1 (castPtr beg2) end0 0
-    return (n1 + n2 + n3)
+    (n1,cont1) <- countBy1 beg0 beg1 0
+    if not cont1 then
+        return n1
+      else do
+        (n2,beg2) <- countBy8 (castPtr beg1) (castPtr end1) 0
+        (n3,_) <- countBy1 (castPtr beg2) end0 0
+        return (n1 + n2 + n3)
   where
     ali = alignment (0 :: Word64)
-    countBy1 :: Ptr Word8 -> Ptr Word8 -> Int -> IO Int
+    countBy1 :: Ptr Word8 -> Ptr Word8 -> Int -> IO (Int,Bool)
     countBy1 beg end n
       | beg < end = do
             ftyp <- peek beg
             if ftyp == 0 then
                 countBy1 (beg `plusPtr` 1) end (n + 1)
               else
-                return n
-      | otherwise = return n
+                return (n, False)
+      | otherwise = return (n, True)
     countBy8 :: Ptr Word64 -> Ptr Word64 -> Int -> IO (Int, Ptr Word64)
     countBy8 beg end n
       | beg < end = do
diff --git a/Network/QUIC/Receiver.hs b/Network/QUIC/Receiver.hs
--- a/Network/QUIC/Receiver.hs
+++ b/Network/QUIC/Receiver.hs
@@ -183,7 +183,7 @@
 processFrame _ _ Padding{} = return ()
 processFrame conn lvl Ping = do
     -- see ackEli above
-    when (lvl /= RTT1Level) $ sendFrames conn lvl []
+    when (lvl /= InitialLevel && lvl /= RTT1Level) $ sendFrames conn lvl []
 processFrame conn lvl (Ack ackInfo ackDelay) = do
     when (lvl == RTT0Level) $ closeConnection ProtocolViolation "ACK"
     onAckReceived (connLDCC conn) lvl ackInfo $ milliToMicro ackDelay
diff --git a/Network/QUIC/Server.hs b/Network/QUIC/Server.hs
--- a/Network/QUIC/Server.hs
+++ b/Network/QUIC/Server.hs
@@ -1,5 +1,3 @@
-{-# LANGUAGE PatternSynonyms #-}
-
 -- | This main module provides APIs for QUIC servers.
 module Network.QUIC.Server (
   -- * Running a QUIC server
diff --git a/Network/QUIC/Server/Reader.hs b/Network/QUIC/Server/Reader.hs
--- a/Network/QUIC/Server/Reader.hs
+++ b/Network/QUIC/Server/Reader.hs
@@ -200,7 +200,7 @@
         logAction $ "too small " <> bhow bytes <> ", " <> bhow peersa
   | ver `notElem` scVersions= do
         let vers | ver == GreasingVersion = GreasingVersion2 : scVersions
-                 | otherwise = GreasingVersion : scVersions
+                 | otherwise              = GreasingVersion  : scVersions
         bss <- encodeVersionNegotiationPacket $ VersionNegotiationPacket sCID dCID vers
         send bss
   | token == "" = do
diff --git a/Network/QUIC/Server/Run.hs b/Network/QUIC/Server/Run.hs
--- a/Network/QUIC/Server/Run.hs
+++ b/Network/QUIC/Server/Run.hs
@@ -1,6 +1,5 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE PatternGuards #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 
 module Network.QUIC.Server.Run (
diff --git a/quic.cabal b/quic.cabal
--- a/quic.cabal
+++ b/quic.cabal
@@ -1,5 +1,5 @@
 name:                quic
-version:             0.0.0
+version:             0.0.1
 synopsis:            QUIC
 description:         Library for QUIC: A UDP-Based Multiplexed and Secure Transport
 license:             BSD3
@@ -9,8 +9,8 @@
 -- copyright:
 category:            Web
 build-type:          Simple
--- extra-source-files:  ChangeLog.md
 cabal-version:       >= 1.10
+extra-source-files:  ChangeLog.md
 extra-source-files:  cbits/*.h
 extra-source-files:  cbits/picotls/*.h
 extra-source-files:  test/servercert.pem
diff --git a/test/FrameSpec.hs b/test/FrameSpec.hs
--- a/test/FrameSpec.hs
+++ b/test/FrameSpec.hs
@@ -46,3 +46,8 @@
                 countZero (beg +. 1) (beg +. 10) `shouldReturn` 9
                 countZero (beg +. 1) (beg +. 11) `shouldReturn` 10
                 countZero (beg +. 2) (beg +. 3) `shouldReturn` 1
+                poke (beg +. 10) (1 :: Word8)
+                countZero beg end `shouldReturn` 10
+                countZero (beg +. 1) end `shouldReturn` 9
+                countZero (beg +. 2) end `shouldReturn` 8
+                countZero (beg +. 3) end `shouldReturn` 7