But here's the thing: in the assembly (the very essence of the essay), booleans are still represented as integers. Using a standard macro would obfuscate the path to getting to the payoff of being able to switch a single byte from 0 to 1 and crack the program, because the author would then have to explain macros and delve into a bunch of ancillary stuff.

Starting to work with Reverse Engineering assumes prior knowledge of programming and/or some basic information about assembly for the specific platform.

Furthermore as the examples are given in C, it is implied that the reader needs to be familiar with the language, and as a consequence, knowing about macros, should be if not a given, then at least required.

The original audience of this content (i.e. not HN) is a broad interest group so you can't really assume that kind of knowledge. Again, think "hey this is neat!" vs "this is absolutely technically correct in all ways."

Of course it should be bool.

I'm glad that the OP at least made it a const char *password though, since that's also a must-have. Always const input pointers. And local temporaries. And everything else that you can const, except scalar arguments pretty much.