Hiring manager gave me a HackerRank test (implement this data structure). He sat back and let me struggle. True to numerous interview guides, I asked clarifying questions and vocalized my thought process. He didn't seem to care. I suspect he was reading email for most of it. After timing out with most of the assignment complete, I said I knew it didn't go great, and asked for advice. He said something like, "you should do more leetcode exercises to sharpen your mind". WOW. Guy doesn't know me, and thinks if I don't remember SelectMany syntax off the top of my head, then my brain is tapioca. And he's a manager! Stay away from this company unless you could care less about human interaction and just want to make a lot of money. You'll fit right in!

Upon joining the meeting, I met with a friendly staff engineer. He asked me for an overview of my background and then immediately jumped into a HackerRank live coding exercise. The coding exercise itself, like many already mention here, is to implement a MultiMap data structure, along with some extension methods. I felt I did well until I got to the intersect method. In my opinion, this coding exercise is flawed because 1) the requirements are unclear; the provided visual diagram describes intersect differently than they expect you to implement it. 2) the interface to the MultiMap class they ask you to implement makes it very unintuitive to use in an extension method. Because I tripped up on one extension method, I was not given an offer, despite having performed well the first hour or so of the interview. They didn't even bother getting to know me or ask about my experience, really. In the future, I am going to start declining interviews at companies that do these leet code / hacker rank challenges. They prove absolutely nothing about what I can do as an engineer, especially in a Principal role. It's no wonder that they have many negative reviews by people currently working there.