Zulip no (which has its own issues from what I read) but they are migrating to mattermost:
> Anyway, we’re moving to Mattermost. This experience has taught us that owning your data is incredibly important, and if you’re a small business especially, then I’d advise you move away too.
> Anyway, we’re moving to Mattermost. This experience has taught us that owning your data is incredibly important, and if you’re a small business especially, then I’d advise you move away too.