I was contacted with a request for a phone screen a few months after I initially applied online. The format of the interview was thoroughly detailed -- diving into a C codebase and making changes -- so I was able to brush up on my C and prepare accordingly. I learned I passed very shortly after the interview concluded and scheduled two further phone interviews.
The format of the next two interviews was industry standard technical LeetCode/HackerRank questions (med-hard). In one of the interviews, I solved the problem given in 30 min and was told to seek the optimal space complexity solution, which was tricky. The interviewer had a laissez-faire attitude and wasn't interactive, which caused some stress. Lacking direction, I may have talked in circles.
The second interviewer was significantly more interactive and conversational; instead of a single large problem, we walked through a series of a problem with escalating complexity of functionality.
I did not pass the second set of phone interviews and make it to the onsite. They did not provide any feedback. I found it strange that they implemented a "diving into a real codebase" interview to test practical software engineering ability and then fell back on the abstract "reverse K-long segments of a linked list"- type questions. Other companies like Stripe focus more consistently on what they are looking for.
