I wrote an article for the Mozilla Hacks blog that's a brief technical introduction to ActivityPub. I also provide an intro to my simple #ActivityPub Node.js server.
@0x1C3B00DA I'm really excited for Pixelfed to get full federation so I can put it side by side with the various Twitter clones and say "look, these run on the same standard". (PeerTube is a little conceptually different since it's federation of metadata plus peer to peer content serving. I think that's extremely important but it complicates the AP story)
Hometown is adapted from Mastodon, a decentralized social network with no ads, no corporate surveillance, and ethical design.