Diaspora did use OStatus back in the early 2010s, at the height of its popularity, and it's easy to find the code in their git repository [1][2][3]. It never in

Diaspora did use OStatus back in the early 2010s, at the height of its popularity, and it's easy to find the code in their git repository [1][2][3]. It never interoperated, of course, because it was borderline impossible to do it. Some of the OStatus code is still there after almost 10 years. Mastodon also used OStatus before ActivityPub existed too, and this is why I'm mentioning OStatus/ActivityStreams: [4][5] ActivityPub was an evolution of ActivityStreams/OStatus, and was started by the same people that wrote StatusNet/Identi.ca/GnuSocial and did the OStatus work in the late 2000s. It's a small group. [1] https://github.com/diaspora/diaspora/blob/e100032244fec9de9cd143bead7a3e36bc8b30f3/lib/salmon/salmon.rb https://github.com/diaspora/diaspora/blob/e100032244fec9de9c... [2] https://github.com/diaspora/diaspora/blob/e100032244fec9de9cd143bead7a3e36bc8b30f3/lib/pubsubhubbub.rb https://github.com/diaspora/diaspora/blob/e100032244fec9de9c... [3] https://github.com/diaspora/diaspora/blob/e100032244fec9de9cd143bead7a3e36bc8b30f3/app/models/post.rb https://github.com/diaspora/diaspora/blob/e100032244fec9de9c... [4] https://github.com/tootsuite/mastodon/blob/8d93f0ca563322764ee4b5395598af542eb678e7/app/controllers/api/salmon_controller.rb https://github.com/tootsuite/mastodon/blob/8d93f0ca563322764... [5] https://github.com/tootsuite/mastodon/blob/8d93f0ca563322764ee4b5395598af542eb678e7/app/workers/pubsubhubbub/delivery_worker.rb https://github.com/tootsuite/mastodon/blob/8d93f0ca563322764...