Slack has said they do not want open source projects to use it.

It is the single most annoying thing about some projects - I get it, IRC doesn't show your emojis, but it just works.

Yeah, I wish they didn't either, but certain projects are mainly slack it seems. I hate it so much for this purpose.

I guess I'm also apart of the problem. :P

Come back to IRC, FOSS!

We recently started using Matrix with riot.im seamlessly bridged to our IRC channels. Seems pretty usable for our needs.

yeah - i do work on 2 projects right now, one on freenode, one on slack. guess which one I look at regularly?

I remember an article about not using slack for FOSS projects, but it was not from Slack. Would you happen to have a link for your claim? I would be quite interested why they would not want to be used by somebody.

That being said I do believe that Slack is a poor choice of medium for a free project, mainly because of the limited history and no publicly searchable transcripts.

And the fact that it costs them a fair amount of money to host large instances of slack.

Can't seem to find the link, but you can see they will give discounts for non profits, up to 250 users. - https://get.slack.help/hc/en-us/articles/204368833

Its a poor medium, as it locks projects into a walled garden ecosystem.

Despite Slack being more polished (particularly on mobile), gitter.im seems like a much better choice for open source projects.