diff --git a/sparrow.cabal b/sparrow.cabal
--- a/sparrow.cabal
+++ b/sparrow.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 309095bf67849fabbab5152d18d36076dcba4000675a82d0129d9a121f9ad671
+-- hash: ca194da829dc469ef7c296f3c390fa1b36df83bd6bff4eee9cab731849fe886e
 
 name:           sparrow
-version:        0.0.2.0
+version:        0.0.2.1
 synopsis:       Unified streaming dependency management for web apps
 description:    Please see the README on Github at <https://git.localcooking.com/tooling/sparrow#readme>
 category:       Web
diff --git a/src/Web/Dependencies/Sparrow/Client.hs b/src/Web/Dependencies/Sparrow/Client.hs
--- a/src/Web/Dependencies/Sparrow/Client.hs
+++ b/src/Web/Dependencies/Sparrow/Client.hs
@@ -166,7 +166,7 @@
             f | tls = runSecureClient (T.unpack $ printURIAuthHost host) (Strict.maybe 80 fromIntegral port) $ T.unpack $ printLocation loc
               | otherwise = runClient (T.unpack $ printURIAuthHost host) (Strict.maybe 80 fromIntegral port) $ T.unpack $ printLocation loc
 
-        x' <- runM (pingPong ((10^6) * 10) x) -- every 10 seconds
+        x' <- runM (pingPong ((10^(6 :: Int)) * 10) x) -- every 10 seconds
         x'' <- runM (runClientAppT (toClientAppT x'))
         f x''
 
@@ -268,6 +268,6 @@
 
   --   Start clients
   z <- runM (runReaderT runSparrowClientT env)
-  evaluate z
+  _ <- evaluate z
 
   wait ws
diff --git a/src/Web/Dependencies/Sparrow/Server.hs b/src/Web/Dependencies/Sparrow/Server.hs
--- a/src/Web/Dependencies/Sparrow/Server.hs
+++ b/src/Web/Dependencies/Sparrow/Server.hs
@@ -279,7 +279,7 @@
                   liftIO (killAllOnOpenThreads env sessionID)
               }
 
-        wsApp' <- pingPong ((10^6) * 10) wsApp -- every 10 seconds
+        wsApp' <- pingPong ((10^(6 :: Int)) * 10) wsApp -- every 10 seconds
 
         (websocketsOrT defaultConnectionOptions (toServerAppT wsApp')) app req resp
 
diff --git a/src/Web/Dependencies/Sparrow/Types.hs b/src/Web/Dependencies/Sparrow/Types.hs
--- a/src/Web/Dependencies/Sparrow/Types.hs
+++ b/src/Web/Dependencies/Sparrow/Types.hs
@@ -4,6 +4,7 @@
   , OverloadedStrings
   , RecordWildCards
   , NamedFieldPuns
+  , RankNTypes
   #-}
 
 module Web.Dependencies.Sparrow.Types where
@@ -35,6 +36,13 @@
   , serverSendCurrent :: deltaOut -> m ()
   }
 
+hoistServerArgs :: (forall a. m a -> n a) -> ServerArgs m deltaOut -> ServerArgs n deltaOut
+hoistServerArgs f ServerArgs{..} = ServerArgs
+  { serverDeltaReject = f serverDeltaReject
+  , serverSendCurrent = f . serverSendCurrent
+  }
+
+
 data ServerReturn m f initOut deltaIn deltaOut = ServerReturn
   { serverInitOut   :: initOut
   , serverOnOpen    :: ServerArgs m deltaOut
@@ -45,15 +53,49 @@
                     -> deltaIn -> m () -- ^ invoked for each receive
   }
 
+hoistServerReturn :: (forall a. m a -> n a)
+                  -> (forall a. n a -> m a)
+                  -> ServerReturn m f initOut deltaIn deltaOut
+                  -> ServerReturn n f initOut deltaIn deltaOut
+hoistServerReturn f g ServerReturn{..} = ServerReturn
+  { serverInitOut
+  , serverOnOpen = \args -> f $ serverOnOpen $ hoistServerArgs g args
+  , serverOnReceive = \args deltaIn -> f $ serverOnReceive (hoistServerArgs g args) deltaIn
+  }
+
+
 data ServerContinue m f initOut deltaIn deltaOut = ServerContinue
   { serverContinue      :: Broadcast m -> m (ServerReturn m f initOut deltaIn deltaOut)
   , serverOnUnsubscribe :: m ()
   }
 
+hoistServerContinue :: Monad m
+                    => (forall a. m a -> n a)
+                    -> (forall a. n a -> m a)
+                    -> ServerContinue m f initOut deltaIn deltaOut
+                    -> ServerContinue n f initOut deltaIn deltaOut
+hoistServerContinue f g ServerContinue{..} = ServerContinue
+  { serverContinue = \bcast -> f $ hoistServerReturn f g <$> serverContinue (hoistBroadcast g bcast)
+  , serverOnUnsubscribe = f serverOnUnsubscribe
+  }
+
+
 type Server m f initIn initOut deltaIn deltaOut =
   initIn -> m (Maybe (ServerContinue m f initOut deltaIn deltaOut))
 
+hoistServer :: Monad m => Monad n
+            => (forall a. m a -> n a)
+            -> (forall a. n a -> m a)
+            -> Server m f initIn initOut deltaIn deltaOut
+            -> Server n f initIn initOut deltaIn deltaOut
+hoistServer f g server = \initIn -> do
+  mCont <- f $ server initIn
+  case mCont of
+    Nothing -> pure Nothing
+    Just cont -> pure $ Just $ hoistServerContinue f g cont
 
+
+
 staticServer :: MonadIO m
              => Alternative f
              => (initIn -> m (Maybe initOut)) -- ^ Produce an initOut
@@ -134,6 +176,14 @@
 -- ** Broadcast
 
 type Broadcast m = Topic -> m (Maybe (Value -> Maybe (m ())))
+
+hoistBroadcast :: Monad n => (forall a. m a -> n a) -> Broadcast m -> Broadcast n
+hoistBroadcast f bcast = \topic -> do
+  mResolve <- f (bcast topic)
+  case mResolve of
+    Nothing -> pure Nothing
+    Just resolve -> pure $ Just $ \v -> f <$> resolve v
+
 
 
 -- * JSON Encodings