[heluser]

Re what other developers use. I tried mermaid and other text to diagram tools for work, but, as mentioned above, found them lacking. Most companies / teams I know of use something like excalidraw or miro. Definitely matches your simplicity requirements, but, obviously, no git blame

[prepend]

I haven’t tried excalidraw, but don’t like miro as I want my docs embedded with the repo, not linking out to a third party.

I like miro for brainstorming and such.