I've started investigating whether a truly "just in time" variant of Tailwind is reasonable. It's almost like a CSS transpiler - converting tailwind classnames to their CSS form.

You'll probably always want AOT for the "critical css" in the first load, but afterward, JIT might be reasonable.

At a minimum, it should be feasible. You can override Prototype's appendChild, replaceChild, and insertBefore to grab classnames and generate CSS before the DOM is updated. Everyone will tell you this is insane, but it seems to work.

But it's unclear if this leads to something "better" than the AOT solution. It feels like code golf: will the transpiler have less bytes than the CSS generated by a pure AOT solution? The tailwind folks have come up with a really dense way of expressing verbose CSS, so I think it's possible!

No affiliation to Tailwind. Just playing on weekends.