[hvidgaard]

It wasn't entirely open sourced last time I researched it, which is one of the reasons I switched to Riot.

[FabHK]

My understanding is that the client code and some of the server code is on github, and the rest of the server side code is being released gradually:

https://github.com/wireapp

https://medium.com/@wireapp/open-sourcing-wire-server-code-e...

https://medium.com/@wireapp