Ask HN: Am I an imposter software engineer?

I learned to code because my company desperately needed engineers. Learning was very slow, and I was never good enough to contribute. Then, I built a (crappy) side project that got some surprising traction, and found myself briefly "CTO" of a startup! We hired some engineers, and though I kept writing code I was not the CTO. The startup failed. This process repeated itself a few more times.

I've now been writing code full-time for 6 years, but always in the same language! I've written hello world apps in a handful of languages and I understand the basic concepts, but every time I start to build a new project, I feel like such a newbie in a new language. I hate googling to debug syntax for some trivial task when I could already have finished the whole project. I also have to go through the learning curve all over again to come up with best practices for that language.

I've worked with a bunch of frameworks, DBs, distros, VCS, etc, so I don't think I'm incapable of learning. There's just something different about your core language.

I fell into doing some part-time contracting work 2 years ago, and I was shocked when a company agreed to pay me $100/hr. Fast forward 2 years later and now I charge $250/hr. I made $400k USD cash last year working reasonable hours. Everything I can find says I'm really well paid. My friends with CS degrees from MIT/Waterloo don't make this much.

The company I consult for the most has asked me to come on full time. They're offering to pay me what I made last year, with more stability and benefits. They want my title to be Principal Architect. A lot of the engineers I work with here come from big software companies you know of, went to great schools, are experts in many languages, etc. They don't make nearly as much as I do. They know my code, but not my background.

Am I an imposter? I don't even feel like I meet the bar for "Software Engineer"!