I solved a generic hackerrack problem and got a perfect score. Pure contacted me to schedule a phone interview. They were upset to hear I was already negotiating salary with another company and offered to fast track my interview process. They did not disappoint. One hour phone screen with an enthusiastic engineer about c++. It's not just a conversation, but a real in-depth reasoning probe. A few days later I was on-site in Mountain View. I had 4 more one hour technical challenges to answer. They varied from "implement this algorithm" to "let's talk about return values". I was completely unprepared in that I didn't try to find out the questions in advance, but the problems were fun and the interviewers were strong advocates for the company. A final interview was set up with the hiring manager who made himself available to answer any questions. In between a couple of engineers took me to lunch, no grading or questions.