[dave78]

Nebula just had a major release that added IPv6 support for overlay networks. Hardly maintenance mode.

The main company working on it now seems to be adding all the fancy easy-to-use features as a layer on top of Nebula that they are selling. I personally appreciate getting to use the simple core of Nebula as open source. It seems very Unix-y to me: a simple tool that does one thing and does it well.