I want to convince myself to write an agnostic #ActivityPub server, and I have a killer name for it that both hits the topic and can take advantage of a new TLD...
The idea for this one is: it has a wide-ranging backend based on AP & the AP C2S API with a smaller server-specific API for what doesn't fit there (I think it'll be mostly admin stuff, like moderating instances). The frontend would be decoupled and the default frontend would also expose the Mastodon API because of course!