There is language knowledge (horizontal) and then there's domain knowledge (vertical).
Language knowledge is not just knowledge concerning its grammar, but about its entire tooling environment. In other words, it is not enough to know how to read/write C++. For example, you also need to be very aware of the vast collection of libraries that exists. Otherwise, you will be reinventing the wheel, badly.
While it is possible nowadays to find gigs just with good language knowledge, you will truly become incontrovertible if you know a particular vertical domain. For example, image processing, or biomedical things, or algorithmical trading, or something else like that.
If you are capable of applying sound language environment knowledge onto such vertical domain with the cash to recruit experts for its needs, the recruitment situation will be such that you can name your price and also dictate the terms of employment: freelance, permanent, work-from-home, or whatever suits you better.
Language knowledge is not just knowledge concerning its grammar, but about its entire tooling environment. In other words, it is not enough to know how to read/write C++. For example, you also need to be very aware of the vast collection of libraries that exists. Otherwise, you will be reinventing the wheel, badly.
While it is possible nowadays to find gigs just with good language knowledge, you will truly become incontrovertible if you know a particular vertical domain. For example, image processing, or biomedical things, or algorithmical trading, or something else like that.
If you are capable of applying sound language environment knowledge onto such vertical domain with the cash to recruit experts for its needs, the recruitment situation will be such that you can name your price and also dictate the terms of employment: freelance, permanent, work-from-home, or whatever suits you better.