Earlier today at TechCrunch Disrupt, Instagram co-founder and CEO Kevin Systrom was on a panel with Eric Ries and Scott Cook talking about Ries’ “Lean Startup” concept. In many ways, Instagram can now be viewed as perhaps the poster child of running lean — they have just six employees and they’re just shy of 10 million users. But it’s about more than just having a small workforce, Systrom says. It’s about staying nimble as you grow. In the video above, we talk about that and a bit more about Instagram.