[SEJeff]

This is great. Also see: https://zulip.org

And the blog on why Dropbox decided to OSS it:

https://blogs.dropbox.com/tech/2015/09/open-sourcing-zulip-a...

[dj-wonk]

> Every conversation in Zulip has a topic, so it’s easy to keep conversations straight.

Threads! Hooray.

[tedmiston]

Also my biggest feature request.

I tweeted it at Slack and they seemed surprised actually. (I didn't get the vibe like they're shipping it anytime soon.)