There's loads of space in a CS career where you'll never get anywhere near responsibility for a hundred thousand much less multiple millions of lines of code at

There's loads of space in a CS career where you'll never get anywhere near responsibility for a hundred thousand much less multiple millions of lines of code at once. And there are already loads of advice out there about how to organize and manage huge code bases. It's usually consultancy based for anything but the broadest ideas though because it's so specific to the particular situation. An architecture is as much defined by the application it's built for as it is by what people would like to impose on it for convenience.