static-assets.txt
My site is <stack> on <host>. When I change the CSS, some visitors see
the old version for days.

Set up assets properly, without adding a build tool:
- A version in each asset URL that changes when the file changes.
- Long cache lifetimes for those assets, and none for HTML.
- Images sized for how they're displayed, with width and height set.
- Loading scripts so they don't block the page.

Give me the configuration for this host and the change to my templates.

Putting a version in the URL is what makes long caching safe. Without it you're choosing between slow pages and stale ones.