It's not zero effort, but it's low effort. Implementing the important features of Slack (specifically the ones you mention) is not hard. I know that because me

It's not zero effort, but it's low effort. Implementing the important features of Slack (specifically the ones you mention) is not hard. I know that because me and one other person did that as a weekend project over a few months[1]. It's not because we're the most amazing developers in the world, but (Sure, not as poslished but that would only take one more designer to fix.) What I'm saying here is that GP is correct, and you are significantly overestimating the value of what Slack provides. They have the mindshare right now, but that's really all. They don't even the benefits a company like Facebook has, since a Slack competitor is still useful if a small number of people use it, as opposed to social media companies who are not useful at all unless they have a large userbase. [1] https://github.com/cicakhq/potato https://github.com/cicakhq/potato