I am mainly into system dev, writing kernels and kinda just building everything from the ground up... But I also like game dev and is interisted in the whole concept. So I am going to make this easy, seing as a lot of things can change the output.

A programmer having 5+ years experience in C++ programming, in the system and also game department... more or less what will they make?

Yes I know that companies will have differing salaries but just more or less.

And then the other thing... Can I do both and be successfull in both?

Unless 5+ is closer to 10+ with an outstanding portfolio, you may want to be more realistic. Game development is extremely competitive, and systems development is difficult to get into due to the lack of open positions.

Though I'd wager systems developers are better paid in general.

A programmer having 5+ years experience in C++ programming, in the system and also game department... more or less what will they make?

Of course, this depends on many factors, with respect to your qualifications, position, and your company's size. Generally speaking, it's around the mid 5 digits (USD), that is, around 50 k$ per year, plus or minus 10-20 k$. A friend of mine's entry salary as a C++ game developer in a small company (about 50 employees) was about 42k$, and grew steadily from there. I would expect similar conditions or better elsewhere.

Can I do both and be successfull in both?

It depends. Certainly, some areas of game development are very similar to system programming, others not so much. The same is true the other way around. But I don't know that you could really do both, unless you do one as a job and the other as a hobby (which would be a lot of coding altogether). But I can certainly see a game developer migrating to system programming (new job, new position), and vice versa, if you realize after some time that you'd prefer the other area.

And as far as I know, when people talk about "system programming" (or also called "infrastructure programming"), game development is included in that category (at least, game engine kernel development). System programming is pretty much any complex software architecture with strict requirements about performance and reliability, which applies to OS kernels, game engines, server applications, and many other applications.

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