I'm curious to see how Joel, Leo, and Tom perceive this open-source version effecting their business.

I'm a long time buffer user, and paying customer, and think that this would actually help the sales pipeline for them. The MVP of Circular is so narrow (given only 1 dev), that it would make me wish for more, and with the attribution Julien gave to Buffer hopefully users will click-through.

Since the Buffer guys have a referral system already in place, maybe you can use Circular to generate some lead gen/affiliate income for you Julien. I would suggest reaching out to them, they are all really cool guys!

Just an idea - best of luck!