So if you DON'T KNOW @evan let me give you some context.
The fediverse really went through three eras, as I see it. The OStatus era, the great fragmentation era, and the ActivityPub era.
If you used "GNU Social", that was StatusNet originally, and it ran OStatus, both of which Evan was largely responsible for. Evan also built the precursor to ActivityPub, the Pump API, and ran the Social Web Working Group, where ActivityPub was standardized!
He's been absent for a while. I'm so happy to see him back!