diff --git a/Devel.hs b/Devel.hs
--- a/Devel.hs
+++ b/Devel.hs
@@ -215,7 +215,8 @@
     putStrLn $ "Yesod devel server. "  ++ terminator ++ " to quit"
     void $ forkIO $ do
       filesModified <- newEmptyMVar
-      watchTree manager "." (const True) (\_ -> void (tryPutMVar filesModified ()))
+      void $ forkIO $
+        void $ watchTree manager "." (const True) (\_ -> void (tryPutMVar filesModified ()))
       evalStateT (mainOuterLoop iappPort filesModified) Map.empty
     after
     writeLock opts
diff --git a/yesod-bin.cabal b/yesod-bin.cabal
--- a/yesod-bin.cabal
+++ b/yesod-bin.cabal
@@ -1,5 +1,5 @@
 name:            yesod-bin
-version:         1.2.9.2
+version:         1.2.9.3
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>
@@ -75,7 +75,7 @@
                      , unordered-containers
                      , yaml               >= 0.8          && < 0.9
                      , optparse-applicative >= 0.5
-                     , fsnotify           >= 0.0          && < 0.1
+                     , fsnotify           >= 0.0          && < 0.2
                      , split              >= 0.2          && < 0.3
                      , file-embed
                      , conduit            >= 0.5          && < 1.2