YMMV and really depends on the startup. I moved from a startup to a big company and back. My very personal experience was this - I learned more in 5 years at AW

YMMV and really depends on the startup. I moved from a startup to a big company and back. My very personal experience was this - I learned more in 5 years at AWS than in my entire 20 years career. Then I moved to start my own company with 2 other amazing co-founders, I can say I learned more in 5 months at my own startup than anywhere else before. My experience from AWS definitely helped, but I think that the pace of learning and managing to "do more with less" (as much as frugality is a leadership principal at AWS, when you run your own seed stage startup, frugality gets a much more realistic meaning) - is orders of magnitude stronger at a startup. If none of your startup peers or founders ever had any corporate experience - while it might be good (big corp didn't "ruin" them yet) it also might mean they will repeat mistakes or have to learn from scratch things that become common knowledge after a few years. How to run effective meetings, business writing, hiring practices, UX, scalable infrastructure and architecture. At AWS, there isn't a distributed systems concept that you can't just find someone who literally wrote the book on it and you can just ping them on slack. So tl;dr - it all depends, I recommend diversifying your career, and just trying it out. I think that a mix of startups and big companies can only do good to your career.