fennell.dev is a Fediverse instance that uses the ActivityPub protocol. In other words, users at this host can communicate with people that use software like Mastodon, Pleroma, Friendica, etc. all around the world.
This server runs the snac software and there is no automatic sign-up process.
Yes, #Dino is packaged for #Debian, too. (I'm doing most of the packaging and uploads, btw.)
The latest version, 0.5.1, is in stable via #trixie #backports, Debian #experimental has the latest git master for the courageous.