I'm very much a beginner at this, so apologies if I'm missing something obvious, but I find this an interesting scenario to think about (so even just to learn h

I'm very much a beginner at this, so apologies if I'm missing something obvious, but I find this an interesting scenario to think about (so even just to learn how you would do it in Elixir would be nice). Why not track the fetching processes in another managing process (or ETS)? Whenever a new request comes in, you check if it there's a process already busy fetching that particular resource. If there is, ask it to send the results back to this request process too, or use whatever storage that keeps this data to satisfy both requests. In practice I'd probably be using some kind of managing process anyways, to deal with queuing multiple requests to 3rd party provider (because rate limiting and whatnot), and I'd perhaps also have some storage and 'inform requesting party of result' logic/process in place too, so I'd not be adding too much extra complexity. Is this a valid approach to begin with? Or does this expose me as very much an Elixir/OTP beginner :)? And if the approach works, what complexity am I missing compared to keeping track of promises in a map? Or am I overestimating how much complexity you're talking about? I had my first taste of doing some 'real' stuff exactly with caching responses and dealing with rate limiting and whatnot, and I found that to be quite nice to do in Elixir, but this particular 'problem' strikes me as one I'll probably run into fairly soon.