I applied online. The process took 4 weeks. I interviewed at PEAK6 (Chicago, IL) in Oct 2018
Interview
As expected, pretty technical heavy with lots of mental math, some tests, etc. all leading up to the in-person interview. The in-person interview was mainly behavioral with a few group activities (escape room, mock trading exercise) to gauge different skills.
Interview questions [1]
Question 1
Very technical mental math e.g. What is the square root of 563?