Fediverse

I don't actually know how nostr deals with messages if you're offline, if at all, not that familiar with the protocol. But your idea sounds workable.

I tend to come at it from the other side, I like the federated model, but think the "supernodes" could behave more like dedicated relays. Like, a lemmy server right now does a lot of things, like serve a frontend, do expensive database queries to show a sorted feed, etc. and a lot of that does not scale very well. So having different kinds of nodes with more specialization, while still following a federated model makes sense to me. Right now if one of my users subscribes to some community, that community's instance will start spamming my instance with updates nonstop, even though that user might not be active or might not even read that community anymore. It would be nicer if there was some kind of beefy instance I could request this data from if necessary, without getting each and every update even though 90% of it might never be viewed. But keeping individual instances that could have their own community and themes, or just be hosted for you and your friends to reduce the burden on non-techies having to self-host something.

Or put another way, instead of making the relays more instance-y, embrace the super instances and make them more relay-y, but tailor made for that job and still hostable by anyone, if they want to spend on the hardware. But I'm still not clear on where you'd draw the line/how exactly you'd split the responsibility. For lemmy, instead of sending 100's of requests in parallel for each thing that happens, a super-instance could just consolidate all the events and send them as single big requests/batches to sub-instances and maybe that's a good place to draw the line?