What this tells me is that if you've reached a six figure salary point, it's time to branch out if you want your income to continue to grow. If you were entry

What this tells me is that if you've reached a six figure salary point, it's time to branch out if you want your income to continue to grow. If you were entry level at $70k, and now you're making $140k as a senior engineer, you're going to have to either do a start-up or add a new, significant skill to your resume if you want to double up again, because you've peaked as "just a developer".