code looks fantastic. Only comments: I would go with Task.Supervisor.start_child instead of async_nolink; async* implies you are waiting to use the function call’s retval, which you are not; this is a “throwaway” situation. Internally in the analysis function I recommend Task.Supervisor.async; you can drop them into MyApp.Analysis.Supervisor (why not?).
as for the value for Registry, I typically put nil in. You’re absolutely right that Registry is confusing because it’s a key-value-value store (and the docs are not 100% clear about that; I had to train a python dev on this and it broke his brain, because he refused to grok the idea of processes); the second value I believe is there to assist in doing process pools, but I haven’t used it myself yet, so I don’t know for sure.
