There is a SDF Mastodon node also, so if you're not into Fosstodon, perhaps it would be a better fit. - I just realized that I have both a Fosstodon and SDF mastodon accounts.
SDF it's self might take a little to explain. But it's kind of a cool place to SSH into. I don't get to as often as I'd like. - And that reminds me that I might want to check my email over there.
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.