There's a lot of it on the Fediverse tech circles. I find a lot of it through following the #Fediverse tag on Mastodon.

Bandwagon.fm: A federated platform for musicians and fans: https://bandwagon.fm/

Bonfire: A modular server for building communities with a wide variety of services: https://bonfirenetworks.org/

write.as: "Type words, put them on the internet." https://write.as/