In 2017, I went to Facebook on a sabbatical from my faculty position at Yale. I created a team to build a storage system called Delos at the bottom of the Facebook stack (think of it as Facebook’s version of Chubby). We hit production with a 3-person team in less than a year; and subsequently scaled the team to 30+ engineers spanning multiple sub-teams. In the four years that I led the team (until Spring 2021), we did not experience a single severe outage (nothing higher than a SEV3). The D...