Affirm Data Scientist interview questions

TL;DR, I expected a hot growth-stage company run by experienced founders and employees to have a professional interview process and was disappointed. It's NOT acceptable to keep a candidate waiting a whole month for an official answer after the onsite interview. I interviewed for a BI/analytics-oriented data science role in spring 2017. I applied through a recruiter I met at an event in SF and had a quick recruiter phone screen, as well as a 30 minute phone call with the hiring manager. After completing a fairly standard take home data challenge, I went in for an onsite that lasted about a half day. The interview itself was more or less fine - some of the discussions around Affirm's business and product were interesting, and the people were very friendly, although I got the sense that the role didn't align well with my interests. One interview slot consisted entirely of whiteboarding complex SQL queries, which was a real head-scratcher. At the end of the day I didn't really feel like i had great rapport with the interviewers or that I was being evaluated on technical/domain knowledge useful to solving real problems. My real issue with the process was the unreliable communication with the recruiting team. At the end of the onsite I sat in my room for ~20 minutes wondering whether it was OK to leave, and had to call one of the contacts on the candidate sheet to get the go-ahead. Also, it took Affirm about 2 weeks just to review the take-home exercise, which is kind of excessive as well. And who keeps an interview candidate in the dark for a whole month after the onsite? Obviously at that point it's a rejection, but it's simply rude and downright unprofessional. My message would be to stop treating recruiting and interviewing as a cost center and really invest in the people and process.

HR phone screening followed by two technical phone interviews, 60 minutes each. One was stats/ML focused and the other one was coding, which to test candidate's implementation skills rather than algorithm knowledge. After that it was a full day onsite, which consisted of 7 1-1 sessions. For the onsite, the first round was about product. There were not much technical questions there; instead it was more like a introduction that helped you prepare for the rest of intensive interviews. The interviewer provided me a lot of insights about their products and business model, which was very helpful, and I liked it a lot. For the rest of the day, there were 4 technical sessions, where 2 of them were open ended that focused on stats/ML knowledge, 1 was closed ended that was more like a pair programming session, and the other one was coding session which also focused on implementation. I had lunch with someone in another team and our conversion was pretty casual, but he asked many behavior questions so I think this was the purpose of this round. Also I talked to the hiring manager to better understand the team and figure out if we were good fit for each other. As I had some time sensitivity, I told the recruiter to increase the process speed and he did make that happened. I finished all interviews within a week and received an offer the following Monday. The recruiter is very responsible and care. He replied messages quickly which made the process pretty smooth. Everyone I have talked to has deep knowledge in their field and is excited about their work. Overall it was a great experience and I think the team is a good fit so I accepted the offer.