I think I know quite a lot about C and C++ (which means Modern C++ (currently C++17)), but have also worked in a lot of other programming languages (including Python, Java, JavaScript, Erlang (additionally, some further ones for university courses)). Additionally to computer science, I studied mathematics, where I also have a doctorate. I wrote my doctoral thesis about some very tricky questions about geometric structures behind optimization algorithms for discrete optimization problems. In all of these areas (mathematics, computer science, doctorate in mathematics), I either graduated with best possible or second best possible mark.
I also claim to know more about IT security than my CV suggests (I got one job interview for a job in this sector, and afterwards the interviewer told me that I have far too much knowledge in this area to be suitable for the available jobs; "you belong into academia").
The same holds, I believe, for embedded programming, where I also think to know quite a lot. Why am I so sure about it? Because as a hobby, I worked on reverse-engineering the firmware of some quite non-trivial embedded device.
I also think that I have an immense knowledge of arcane details of the instruction encodings of various CPU architectures, but this is merely a hobby of mine and useless for the job market.
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There exist lots of people who seriously could not understand how I could not find a job as a programmer. For example quite some doctoral classmates (who could find a job in software development) called me a "wandering encyclopedia of the history of computer science".
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As I said: I found a job in a sector that is very different from software development. Just don't tell me that it is easy to find a job in software development; it isn't, even if you are willing to relocate anywhere in Germany or Austria. And I know quite some people who have the same experience.