Discourse is modern forum software for your community. Use it as a mailing list, discussion forum, long-form chat room, and more! Link: https://www.discourse.org/
Discourse is being considered by some members as an alternate forum for Pumping Station: One, to augment or supplant Google Groups.
In 2017 the DNS entry for the then-idle Discourse instance was removed.
Discourse was turned off on 2017-05-04. The backup of the data/messages in the forum is being held by the CTO.
How to stand up things to use the member site credentials for logging in to discourse
How to allow people to create categories
How to make hats
I can't remember what else.