Thank you for sharing, because I didn't know what cloud-init was until your post. I've done something similar, but packaged as a library of bash functions, designed to be called in arbitrary order. I cannot comment on the specific decisions you made in your file, but the fact that a declarative, compact, and standard solution exists for this problem is music to my ears. Out of curiosity, where did YOU learn of the existence of this feature?
> It is slowly being outcompeted by Ignition and the friends, though.
I hope not, because I lack enough foul language to describe my burning hatred for Ignition and all its cutesy campfire-related project codenames. Hate-red.
Looks like it was invented by Canonical for AWS/EC2 in 2006 (!). It was then gradually adopted by other clouds over the next 10 years or so (GCP adopted in 2013, Azure a couple years later). Linode (Akamai Cloud now, I guess) adopted in 2023. Obligatory xkcd: https://xkcd.com/1053/
This got me to wondering when I first heard about HTML, HTTP, Linux, UTF-8, or any number of things, and from where, how so many of the things I've heard of once and never again, and the many important "standard" things I've never heard of.