diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # Revision history for greskell-websocket
 
+## 0.1.1.1  -- 2018-09-23
+
+* Confirm test with `stm-2.5.0.0`.
+
+
 ## 0.1.1.0  -- 2018-08-17
 
 ### Client module
diff --git a/greskell-websocket.cabal b/greskell-websocket.cabal
--- a/greskell-websocket.cabal
+++ b/greskell-websocket.cabal
@@ -1,5 +1,5 @@
 name:                   greskell-websocket
-version:                0.1.1.0
+version:                0.1.1.1
 author:                 Toshio Ito <debug.ito@gmail.com>
 maintainer:             Toshio Ito <debug.ito@gmail.com>
 license:                BSD3
@@ -52,7 +52,7 @@
                         unordered-containers >=0.2.8 && <0.3,
                         uuid >=1.3.13 && <1.4,
                         async >=2.1.1.1 && <2.3,
-                        stm >=2.4.4.1 && <2.5,
+                        stm >=2.4.4.1 && <2.6,
                         websockets >=0.10 && <0.13,
                         hashtables >=1.2.2.1 && <1.3,
                         safe-exceptions >=0.1.6 && <0.2,
diff --git a/src/Network/Greskell/WebSocket/Connection/Impl.hs b/src/Network/Greskell/WebSocket/Connection/Impl.hs
--- a/src/Network/Greskell/WebSocket/Connection/Impl.hs
+++ b/src/Network/Greskell/WebSocket/Connection/Impl.hs
@@ -89,7 +89,7 @@
                                    }
   where
     codec = Settings.codec settings
-    qreq_size = Settings.requestQueueSize settings
+    qreq_size = fromIntegral $ Settings.requestQueueSize settings
     ws_path = Settings.endpointPath settings
 
 -- | Close the 'Connection'.