Actually, now that I think of it there should really be some kind of federation feature on #Sonarr. I'm not sure if ActivityPub would be appropriate for it, but it might. They already have the "monitored status" thing, maybe one could use this to indicate to federating servers (manually added one by one) what files they want, and then whoever gets the file notifies others that they have it, who can then sync it. This way you could federate with family or friends? I have to think about this a bit
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