Mozilla Data Scientist Interview Questions
& Process

First, I spoke with the recruiter on the phone. Then I had an interview with the hiring manager. After that, there were two technical interviews covering applied statistics in AB testing, Python, and SQL. This was followed by a virtual on-site interview. During the on-site, I was given a set of questions to work on and answer, and I had to prepare and deliver a presentation to a panel of three people (peers and managers) within two hours. I also interviewed with a manager and a stakeholder who works closely with data scientists. The day after the on-site, the recruiter gave me feedback. The entire experience was positive and respectful of my time. The process felt like a good preview of the actual job, and the questions weren't designed to be unfairly difficult.

The whole process from applying to finishing the interviews took 5 weeks, maybe 4 weeks but I was moving and took a week off. The recruiter was always quick to respond, usually within a few days or sometimes hours. It went like this: recruiter phone screen, then a video call with the hiring manager, followed by a 2 hour SQL/Python and Applied Stats interview. Then a 2 hour data challenge with a 30 min presentation and panel interview. Lastly, two 30 min interviews about product and policy. Everyone was nice and professional. I didn't get the job because they wanted more senior people, but I appreciated the feedback.

It started with a phone screen. About a month later, I had two technical interviews, one focused on Python/SQL skills and the other on statistics, all conducted via their video call platform. The first interview had one interviewer, while the other two had two interviewers each. Despite their efforts to organize, I found the overall process to be quite disorganized.