diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # ChangeLog for monad-logger
 
+## 0.3.36
+
+* Export the `defaultOutput` function, useful for defining custom instances of `MonadLogger`. [#29](https://github.com/snoyberg/monad-logger/pull/29)
+
 ## 0.3.35
 
 * Add Hackage status badge
diff --git a/Control/Monad/Logger.hs b/Control/Monad/Logger.hs
--- a/Control/Monad/Logger.hs
+++ b/Control/Monad/Logger.hs
@@ -103,6 +103,7 @@
     -- $locDocs
     , Loc (..)
     , defaultLoc
+    , defaultOutput
     ) where
 
 #if WITH_TEMPLATE_HASKELL
@@ -664,6 +665,18 @@
     return (UnliftIO (unliftIO u . flip runLoggingT f))
 #endif
 
+-- | A default implementation of 'monadLoggerLog' that accepts a file
+-- handle as the first argument.
+--
+-- This is used in the definition of 'runStdoutLoggingT':
+--
+-- @
+-- 'runStdoutLoggingT' :: 'MonadIO' m => 'LoggingT' m a -> m a
+-- 'runStdoutLoggingT' action =
+--     'runLoggingT' action ('defaultOutput' 'stdout')
+-- @
+--
+-- @since 0.3.36
 defaultOutput :: Handle
               -> Loc
               -> LogSource
@@ -674,13 +687,14 @@
     S8.hPutStr h ls
   where
     ls = defaultLogStrBS loc src level msg
+
 defaultLogStrBS :: Loc
                 -> LogSource
                 -> LogLevel
                 -> LogStr
                 -> S8.ByteString
 defaultLogStrBS a b c d =
-    toBS $ defaultLogStr a b c d
+    fromLogStr $ defaultLogStr a b c d
   where
     toBS = fromLogStr
 
diff --git a/monad-logger.cabal b/monad-logger.cabal
--- a/monad-logger.cabal
+++ b/monad-logger.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: c1da2cf4e6349e1b417f173c13880cb9929fece82971108834a71f9eb72a6d69
+-- hash: ae72d70b6bc9b10cacdb9b7f8ea8d66a762c3eab2f3799c2749514255181ebfe
 
 name:           monad-logger
-version:        0.3.35
+version:        0.3.36
 synopsis:       A class of monads which can log messages.
 description:    See README and Haddocks at <https://www.stackage.org/package/monad-logger>
 category:       System