30 minute phone conversation; we talked on the phone, they asked about what I knew, what programming languages, what technology stack I was familiar with, etc.. It was very informal, and relaxed, actually quite nice compared to typically stressful technical interviews. I was actually surprised when they offered the position after about 30-45 minutes, since I had no idea that I was actually being interviewed for a job, and a decision was being made there. Spoke with multiple members of the team I'd be working with.