Meta Research Scientist I interview questions

talking to the hiring manager. He is very polite and friendly. Asking my research interests and experience. I feel that he is a nice guy. However, a few days after the interview HR told me that I'm rejected :( Maybe they were not so nice after all.

1 round phone screen: 2 leetcode medium code 4 rounds virtual onsite: 2 coding, 1 machine learning system design, 1 behavioral question round Get the final notification two weeks after the final interview.