Ours is indeed a decadent universe that is slowly being corrupted by powerful forces of evil (such as the 4-space tab brain damage of github). But there are still beacons of light to guide us:

https://www.kernel.org/doc/html/latest/_sources/process/codi...

https://wiki.musl-libc.org/coding-style.html

https://www.freebsd.org/cgi/man.cgi?query=style&sektion=9

https://man.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man9...