I thoroughly investigated every open-source (mostly open-core) self-hostable Slack alternative, and the conclusion was clear: only a self-hosted Matrix is a viable option.
There are no arbitrary limits for 'community editions', no risk of relicensing, no risk of being held hostage for features (like Gitlab did at some point).
You can work around all the missing features easily with self-built webhooks and other tools.
Starting with Mattermost or Zulip or similar is just way too risky.
What about their mobile push notifications? I don’t understand whether that’s something one can self-host. I have just read Zulip’s https://zulip.readthedocs.io/en/latest/production/mobile-pus... and they give me the impression only they can do this, so ‘pay us money or else’
I wonder whether this is something any other provider can rug pull in the figure and to be worried about.
There are no arbitrary limits for 'community editions', no risk of relicensing, no risk of being held hostage for features (like Gitlab did at some point).
You can work around all the missing features easily with self-built webhooks and other tools.
Starting with Mattermost or Zulip or similar is just way too risky.