I think the common denominator is to optimize for happiness. Most of us ended up in software development because we were curious about technology in the first

I think the common denominator is to optimize for happiness. Most of us ended up in software development because we were curious about technology in the first place. Learning stuff and tinkering with stuff makes us happy. We should continue to do so. The section about optimizing your career is also about optimizing your happiness. There will be plenty of times where the sirens try to lure you into taking on tasks which are financially rewarding but boring. Take on some of these but don't get trapped forever in a local minimum. Your strategic goal is to feed your curiosity and your happiness. The part about finding a mentor I'd phrase more broadly as: find a network. Find friends. Hang out with people who are fun to hang out with and who care about tech and life in general. They'll probably have strong opinions, and so will you. You'll learn a lot from these people; they'll be the mentorship that you need. And why would they want to hang out with you? Because you are bright, curious, and because people that optimize for happiness are great to hang out with.