This is a review of the interview process in general and is not related to specific interview questions. TLDR: They cold DM'd me on LinkedIn out of the blue and then ended up ghosting me after 5ish interview rounds over many weeks. More details: I received a LinkedIn message from a senior technical person at Abnormal; I wrote back and the interview process proceeded roughly as normal, with the usual recruiter screens, tech interviews etc. It did seem notable that I met the same people several times in interviews that seemed very similar to each other, even to the point of being duplicates. They also have a "group interview" stage, the premise of which is like "Give a talk or a demo about some prior work, and we'll ask questions" etc. They seemed to want a lot of preparation for this, and seemed mildly salty/surprised that I reused a pre-existing talk+slides. For more than a month I jumped through many many of these duplicate-interview hoops, group interview hoops, and the usual tech/coding interviews, altogether roughly 5ish rounds by my approximate count. Then they ghosted me after a fairly long (and possibly unnecessarily-elaborate) interview process. The morale of the story: Beware of sinking a lot of time into this company; they seem smart and friendly and generally competent, but the process can burn a lot of your time and effort, and they do not seem to be self aware enough to realize how "abnormally" time consuming their hoop-jumping is.