Yeah, most of these repositories contain more files than caffeinate+ has lines of code.

The API call that 'sudo pmset -a disablesleep 1' does is literally the first thing caffeine+ does. But is only part of the full solution: As soon as the lid closes the command is automatically reverted so you can't forget to do it yourself. Also if you kill caffeinate+, the MacBook is put to sleep when the lid is still closed.