I have a ConduitParser https://hackage.haskell.org/package/conduit-parse-0.2.1.0/docs/Data-Conduit-... (a Sink with some parsing state) with a version of satisfy that can time out: satisfy :: MonadIO m => (a -> Bool) -> ConduitParser a m a satisfy pred = do tId <- liftIO myThreadId timeoutThread <- liftIO $ forkIO $ do threadDelay 1000000 throwTo tId TimeoutException x <- await liftIO $ killThread timeoutThread if pred x then return x else empty However I would rather not deal with the risks involved with handling concurrency myself and use a system library like System.Timeout: satisfy :: MonadIO m => (a -> Bool) -> ConduitParser a m a satisfy pred = do x <- timeout 1000000 await if pred x then return x else empty This doesn’t work though since I need to be able to both lift and unlift await from IO, and ConduitParser lies on top of ConduitT, which is one of the types of monads that UnliftIO cannot be an instance of https://github.com/fpco/unliftio#limitations. Are there any better approaches to this? https://github.com/fpco/unliftio#limitations https://github.com/fpco/unliftio#limitations https://github.com/fpco/unliftio#limitations