I'm a fan of https://www.ilograph.com/. I've only used it for a few small things, but the author has good samples, including a diagram of ilograph itself - https://app.ilograph.com/demo.ilograph.Ilograph/Request.
Readit Newsaetherlord commented on Ask HN: Visualizing software designs, especially of large systems (if at all)? · Posted by u/lovehatesoft
aetherlord commented on Why are we templating YAML? leebriggs.co.uk/blog/2019... · Posted by u/jaxxstorm
I didn't see this mentioned anywhere else, so another alternative (that I've seen and really like conceptually, but haven't used so far) to all this wildness with YAML and JSON -> https://github.com/dhall-lang/dhall-lang, and for kubernetes specifically -> https://github.com/dhall-lang/dhall-kubernetes
RASH, RAcket SHell library and language: https://github.com/willghatch/racket-rash
Note: I am not the author