For more, see https://news.ycombinator.com/item?id=14836340 (Ask HN: In what creative ways are you using Makefiles?).

I use a build system, redo rather than make, to rebuild my GOPHER site and Debian/FreeBSD package repositories. (https://news.ycombinator.com/item?id=14837740 https://news.ycombinator.com/item?id=14928216)