I was contacted on LinkedIn by a recruiter. The recruiter was extremely professional and helpful. He gave me the good advice to prepare for 1 or 2 easy/medium LeetCode questions for the phone round every day for 3 weeks, and I did exactly that. I bought the LeetCode Premium package, where I was able to do the Facebook track. Many questions I encountered throughout the process were similar to ones there.

For the phone round, I was asked 3Sum plus a bunch of SQL questions related to department/salary and applied/recruiter data sets, which you can find on Glassdoor and LeetCode. Some SQL questions were slightly tricky, and I was glad I had prepared. The interviewer was passionate about his job and answered a lot of questions.

I set up the onsite soon after the phone round. The recruiter sent me a lot of material and also did a phone call to help prepare. As I started preparing for the onsite interview and reading a little about the role, it appeared that the Data Engineer role at Facebook is not as appealing as the Software Engineer role. This was validated during the interview, where I learned that 2 of the interviewers were transitioning to Software Engineering roles. This was a red flag for me because I have a long and solid background in CS and Data Engineering. The product sense question was confusing because I wasn't sure what the interviewer wanted, but I guess they just wanted an ERD and database schema. Perhaps they should call it that, because I started with client-server diagrams, etc., which were not needed. I did enjoy some of the ETL questions; it was fun to solve them. The behavioral round was also fun. I was skeptical, but the time went by quickly.

The recruiter had sent some very good material that helped me with other interviews as well. I should add that I interviewed for the Enterprise Engineering team, which I learned during the process supports the Product team. If it had been more clear to me, I would have probably tried to interview in the Product team, because it looked like people were trying to move from Enterprise Engineering to Product.

Overall, it was a good process. I did not get an offer, but I was hooked up with another recruiter at Facebook where they thought I might be a good match. I chose not to pursue that.

3Sum, lots of SQL.