Uber Front End Engineer interview questions

Short skype talk with recruiter, followed by one hour online technical interview. It had a couple of general front-end questions and a bit of algorithms. The online interview with the technical person was actually the most pleasant experience during the interview process. Took them one week to give me feedback for that and gave me one coding challenge to complete in 10 days. Got feedback on that exactly 3 weeks after submission and was rejected for superficial reasons (not enough lines of code).