any suggestions how to guard against that? thanks too

I guess I could not expose the in channel..

you should check the return value on every channel read and channel write, and have a graceful exit or recovery for nil

this also means you don't necessarily need a sentinel value for early exit - you can just document that closing the in channel means you wrap things up

nice

if you study the functions in clojure.core.async, they follow that pattern: closing a channel they use is accepted as a way to make them exit if apropriate

that's a great idea, will do

this code lives in a component, so was thinking of something to shut it down

should I do any other cleanup?

draining any values I suppose

that depends on your domain, letting the channels go out of scope should suffice to release resources