Capital One Full Stack Developer interview questions

As many have posted, I had a 30 minutes phone screen with one of the developers then a half day onsite. Two of my interviewers, including the hiring manager, were unavailable for the interview so two others were asked to pinch hit, but this was fully disclosed to me by the folks involved. I think some of the confusion was the result of my recruiter being a contractor, not a CapOne FTE himself. The interviews were behavioral -- a discussion with a ScrumMaster -- technical -- a discussion with another developer -- and a fill-in for the hiring manager that repeated much of the behavioral. Then there was a programming assignment, detailed below.