I could erase all but two of the jobs in my entire career history with no substantial impact on my engineering skill. These two jobs were my 10x jobs.
Silicon Valley has popularized the concept of the 10x engineer: an engineer that does in one hour what an average engineer does in ten.
Similarly, my 10x jobs had a disproportionate impact on my skill development. They challenged me, but not in the traditional sense of long hours and burnout. Instead, they demanded that I bring my all my focus to work and to scrutinize my beliefs and decisions. They're the growth spurts of my career.
My 10x jobs combined mentorship and ownership to create an ideal learning environment
To start, in both roles, I had a mentor. The fact that this was rare makes it easier to believe most jobs had little impact on my skill development.
Both my mentors gave me copious and direct feedback on my work. One of them constantly asked me "why do you think that?" with genuine curiosity. I often didn't know, and I loved being forced to think about it.
I was on small teams for both these jobs and I had broad ownership over everything I touched. At larger companies, if I ran into an issue not directly related to my day-to-day, I could find another team to look into it.
At my 10x roles, I was responsible for fixing pretty much any problem I came across. This responsibility exploded the breadth of my expertise.
It's worth saying I don't regret my non-10x jobs. They helped me achieve financial goals or meet great people. They just didn't move the needle much on my skills.
If you're looking for a 10x job though, seek mentorship and ownership. You may find yourself growing much faster than you thought you could.