The most responsive interview process I've had. I applied for the position online and the technical recruiter reached back to me the next day. She asked about my background and I was given the choice of either submitting a code project I was proud of or completing a coding challenge within a week. I opted for the coding challenge and spent an entire weekend implementing it. I was then arranged a phone-screen with a senior software engineer. The phone interview was a live coding session and we had to implement a feature on the browser together. Later that day, I heard back from the recruiter and she invited me to fly to San Francisco from Toronto for an onsite interview. The onsite interview consisted of four separate rounds of 45-minute interviews. The first three rounds each had two engineers and I was asked to write working code and design on the whiteboard. Each round tested knowledge on a specific domain: in-depth coding, architecture design, breadth of knowledge. The last round was a design discussion with an engineering manager. I heard back from the recruiter the next morning and was presented with an offer.