[devoutsalsa]

I've never used Mattermost before today. After checking out their site, I can see they are also a for-profit company. What does Mattermost offer that Slack does not, other than a bill lower than $195K/year?

[actionfromafar]

You can deploy it self-hosted without paying any fee, so you control your data much more.

[wltr]

Last time I checked they cripple the self-hosted version, asking to subscribe for enterprise plan here and there. Source: deployed their chat locally a couple of weekends ago. Overall, I liked their Slack clone, they this one was a red flag to me. Now I’m not sure we want to deploy this, but I know very little alternatives. Zulip, but it cripples its self-hosted version too. It allows just 10 mobile users (notifications). Maybe Matrix it is then, but it’s not very suitable for airgapped company-wide deployment.

[ForHackernews]

Mattermost is open-core software: you can self-host and they can't turn you off or raise the price.

[pcthrowaway]

What's your case for calling it open-core? The whole thing is AGPLv3, so... I'd call it FOSS with some components optionally being usable under Apache 2 terms