But it's an actual product that, for all that, basically works. And millions of real people do real work with it every day.

I find Michael Meeks' tech reports really interesting, because they show how on earth a small band of very high-calibre software engineers can possibly maintain a several-million-line codebase with far too few people.

The answer is automation, directing slogging through. Unit tests, automatic code checkers, Coverity, clang plugins, assorted torture tests ...

It's a useful example of how too few people can effectively maintain and develop a huge codebase. This is knowledge the world will need for the future, as software continues to expand as absolutely large as it can.