jrollans.com 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.
I have not seen a replacement for gup(.)pe groups yet. Small instances need such a service to reach others.
Our NGO has reserved the guppe(.)org domain and we will donate it to whoever can provide that service.
Alternatively, we will set it up using that domain as long as we can get some tech folks to help us.
Here's a link for more info - we have not heard back from anybody yet.