When I was 28 I had been bouncing around startups for almost a decade. I had met some smart people and worked on one or two things I was proud-ish of, but I had

When I was 28 I had been bouncing around startups for almost a decade. I had met some smart people and worked on one or two things I was proud-ish of, but I hadn’t really learned much in years, and nothing I had done was very notable. No college degree, kind self-taught web programmer, very little CS knowledge. The startup I was working for was going under, and I got serious about finding a job where everyone would know more than me. The prospect of unemployment/insolvency didn’t hurt my motivation! There wasn’t leetcode then, but I hit the books in a big way, having already flunked some big name interviews over the years. The thing is I had been picking up CS a little at a time, and that time the books were still hard but not hopeless like before. When I actually did the next round of interviews no one was more surprised than I was that I could avoid getting completely run over in a whiteboard interview. The thing is the crazy-hard ones are regrettably common, but they say more about the interviewer than the candidate. Leetcode questions routinely involve tricky identities that you just have to know and other stuff that is absurd to ask in 30 minutes on a whiteboard. There are lots of interviewers at prestigious companies who ask very reasonable (“leetcode easy”) questions. People do pull out the upper-division combinatorics crap, but that’s stupid, not you. Getting a truly challenging job didn’t fix all the problems in my life, but I learned so much, so quickly that it re-inspired me about my career in a way that never went away. So: 28 isn’t too late, you don’t need a CMU degree, and if cast a reasonably wide net you can find an interviewer who isn’t a jerk. You’ll still need to know about some CS stuff, but not the upper-division or even graduate stuff that pops up sometimes on leetcode and in some interviews. If you fail a whiteboard interview and you’re like “damn I should know that”, study a bit more. But if it’s some off-the-wall shit: it’s them, not you.