WebSub + RSS/Atom is a good option for relatively slowly changing data. (Maybe at most a couple of times an hour). It is nice because it is opt-in and an enhanc

WebSub + RSS/Atom is a good option for relatively slowly changing data. (Maybe at most a couple of times an hour). It is nice because it is opt-in and an enhancement on the regular polling API. Using WebSub or UnifiedPush would technically very similar but you need a way for the client to pass you the subscription information. WebSub has a standard discovery process to manage this.