[nyconyco]

Oh Mircosfot's strategy is the weirdest: OCS, Lync, Skype, Skype for Business, Teams, Yammer... People are just lost.

Nayego is trying to hard build a HipChat-like client+server that is open source and based on XMPP. https://nayego.net/ you can subscribe if you want to see a preview.