This is an excellent explanation of make! The only thing I will add is the slightly more abstract thought that make is meant to build files out of other files based on timestamps of the source files. And the target files can themselves become source files, which means that you can build dependency graphs. Lastly, it has “caching” built in: if bar.o is newer than bar.c, don’t rebuild it. If it doesn’t exist or is older, do rebuild it. So when you change one file, you don’t recompile the entire damn tree.

It also has “phony” targets that aren’t files. The canonical example of this is “clean” which basically just does something like rm -rf *.o fooexec

This is what the JavaScript tooling people have been chasing for the past 15 years and can’t seem to grasp. Someone actually did build a make-based build system I believe but it never got popular because it wasn’t written in JavaScript.