It seems to be indeed Mattermost as a service 😀

Yeah, the high-performance backend is — sadly! — no good for us.

Thank you for the summary!

No, if it is too complicated for me – it will be too complicated for 95 % of our potential “users”.

I’ve mentioned Rocket.Chat in my initial post, and isn’t Stoat “just” Revolt?

It seems Zulip is the Slack alternative you wish for?

Hey, thanks for the recommendation. Delta doesn’t offer the features we need.

Sadly there is nothing you could call an IT budget. As with many small-to-mid-sized institutions.