Just to be clear, Zulip is not Open Core. We are 100% open source software, in contrast with Mattermost, GitLab, and many (most?) other VC-funded applications marketed as "open source".
I think this is a really important distinction; the VC-funded open core business model has a fundamental incentive structure that pushes the company to makes its open source project an intentionally crippled demo product so that they don't miss any revenue they might have had as a proprietary product.
I think this is a really important distinction; the VC-funded open core business model has a fundamental incentive structure that pushes the company to makes its open source project an intentionally crippled demo product so that they don't miss any revenue they might have had as a proprietary product.