I'm one of the developers working on Trustroots.

We're working on references :) I merged this PR yesterday https://github.com/Trustroots/trustroots/pull/1413, there is a bit more to work out for displaying them...

There is also a meetup feature already (see https://ideas.trustroots.org/2017/08/21/meeting-people-now-o...), it's a bit primitive right now, but it was a first iteration, and we've been discussing some next steps recently.

We are also open source! https://github.com/trustroots/ (with a node + react stack)