I'm ready to start building my custom wp-cli stuff, but I'm not sure where I should put my code. I found https://make.wordpress.org/cli/handbook/internal-api/wp-cli-add-command/ which is good, but not good enough.
It'll be very useful to point readers of this page of to a place where they learn more about where to actually add this example code. This could also be on the page itself.
I'll be happy to do a pull request for this if/when I figure it out on my own.