diff --git a/Yesod/Core/Content.hs b/Yesod/Core/Content.hs
--- a/Yesod/Core/Content.hs
+++ b/Yesod/Core/Content.hs
@@ -63,6 +63,9 @@
 import Data.Conduit (Source, Flush (Chunk), ResumableSource, mapOutput)
 import Control.Monad.Trans.Resource (ResourceT)
 import Data.Conduit.Internal (ResumableSource (ResumableSource))
+#if MIN_VERSION_conduit(1, 2, 0)
+import qualified Data.Conduit.Internal as CI
+#endif
 
 import qualified Data.Aeson as J
 import Data.Aeson.Encode (fromValue)
@@ -114,6 +117,11 @@
     toContent = toContent . renderCss
 instance ToContent Javascript where
     toContent = toContent . toLazyText . unJavascript
+
+#if MIN_VERSION_conduit(1, 2, 0)
+instance ToFlushBuilder builder => ToContent (CI.Pipe () () builder () (ResourceT IO) ()) where
+    toContent src = ContentSource $ CI.ConduitM (CI.mapOutput toFlushBuilder src >>=)
+#endif
 
 instance ToFlushBuilder builder => ToContent (Source (ResourceT IO) builder) where
     toContent src = ContentSource $ mapOutput toFlushBuilder src
diff --git a/yesod-core.cabal b/yesod-core.cabal
--- a/yesod-core.cabal
+++ b/yesod-core.cabal
@@ -1,5 +1,5 @@
 name:            yesod-core
-version:         1.2.19.1
+version:         1.2.19.2
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>