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Cyphase (Mar 29 2020 at 08:24):Christian Williams said:
[Though like every free version there is some limit; this chat only hold the most recent 10000 messages. If we want no limits, we can host one ourselves: https://zulip.readthedocs.io/en/stable/production/install.html .]
I don't speak for them, but zulipchat.com is very generous with upgrading plans for communities like this. Worth an inquiry. See their plans page, which says:
Zulip Cloud Standard is free for open source projects. We also offer steep discounts (usually 85%-100%) to many non-profits, educational institutions, groups of friends, and in other scenarios where most of the users are not fulltime employees of the customer. Generally, only closed organizations that also pay their members’ salaries pay full price. Just contact sales@zulipchat.com and we’d be happy to discuss your situation!
EDIT: (I should have put this in #meta; hopefully it'll be movable soon.)
Christian Williams (Mar 29 2020 at 16:57):Yes, it has already been upgraded; we're good. Thanks though.