[ciferkey]

I've been collecting a history of this sort of thing, and list of companies here: https://blog.matthewbrunelle.com/on-self-hosting-opentofu-an... . I'll have to add this one.

Let me know if there's more I can include!

[bityard]

There's also https://isitreallyfoss.com

[halfmatthalfcat]

Akka by Lightbend (now called Akka)