Hello. I have next problem: I have a network client that connects to server, listens for messages and generate responces. So the control flow can be represended as: server -- input -> {generate output} -> output Output can be generated using default implementation or can overriden by user. The main difficulty appeares when I need to add a user program on the top of this logic, i.e. from user-side I want to have dsl:smth like withClient $ do x <- send message waitFor x timeout 5000000 forever $ sendRandomMessage i.e. an ability to send messages, waiting for some event (message to come), waiting for timeout. The question is how to define such logic without a big overhead. I see a solution using conduit, it's possible to create 3 processes: listener, user, sender. +----> user ----+ | | -input -> listener +----------------->+---- sender -> and use TQueue or TChan to send messages between them, however there can be another possible solutions, that uses less resources, or another design. -- Alexander