There were 3 stages in the application process: online submission of the CV + phone interview, over the weekend coding challenge, and on-site interviews. It was one of the best interview experiences that I've had. The 2 things that I appreciated the most were how fast they moved throughout the entire process (applied online in the morning and received phone interview invitation in the afternoon), and how friendly and open the people I interacted with were. The coding challenge wasn't a typical data structures and algorithms problem, but one that offered me more liberties in how to approach it.