[jitsi-dev] last-n configuration

I just read the article you guys published on https://developer.atlassian.com/blog/2015/07/video-conferencing/ and was wondering if in order to enable that I need latest git head for both JVB and jitsi-meet or if the versions currently pushed out of the Debian repos have that ability also?

Are there any instructions anywhere on how to go about configuring this? Does it involve settings on both JVB and jitsi-meet?