diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,3 +2,6 @@
 
 ## V0.3.0
 - Add `RotatingFileHandler` (without unit tests)
+
+## V0.3.1
+- Fix `defaultRoot` format bug
diff --git a/log4hs.cabal b/log4hs.cabal
--- a/log4hs.cabal
+++ b/log4hs.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: e7e350195d12d645cff1909da7ee473c97ec7d76c3116dc59cd50b3d7d294f14
+-- hash: 90b0b17510bc8c4fc178da4193122aee38d748d65201c114cd6c51476b45cb3e
 
 name:           log4hs
-version:        0.3.0.0
+version:        0.3.1.0
 synopsis:       A python logging style log library
 description:    Please see the http://hackage.haskell.org/package/log4hs
 category:       logging
diff --git a/src/Logging/Internal.hs b/src/Logging/Internal.hs
--- a/src/Logging/Internal.hs
+++ b/src/Logging/Internal.hs
@@ -124,11 +124,11 @@
 
 -- |A 'StreamHandler' bound to 'stderr'
 stderrHandler :: StreamHandler
-stderrHandler = StreamHandler def [] "" stderr
+stderrHandler = StreamHandler def [] "{message}" stderr
 
 -- |A 'StreamHandler' bound to 'stdout'
 stdoutHandler :: StreamHandler
-stdoutHandler = StreamHandler def [] "" stdout
+stdoutHandler = StreamHandler def [] "{message}" stdout
 
 {-# NOINLINE defaultRoot #-}
 -- |Default root sink which is used by 'jsonToManager' when __root__ is missed.