[coddle-hark]

> Any web application with a UI _requires_ a frontend build for CSS/JS.

Except it really doesn't. Core web technologies have gotten so much better since the jQuery/pre-SASS days that you can absolutely get by without a build step.

- http/2 makes bundling a questionable choice

- polyfills are pretty much no longer a thing

- CSS now has most (all?) of the features that people used SASS for (variables, nesting, etc.)

- es6 modules work

This has been a big talking point in the Rails community lately — one of the big selling points of Rails 8 was the fact that you can, by default, ship a whole webapp without a build step, and that this is considered the "happy path".

[flimsypremise]

In web application terms, the "build" is everything that needs to happen to get your application running into production. That means a runtime and dependencies. Speaking of dependencies, does your perfect frontend simply not have any of them? Is every tool you will need to use perfectly packaged with vanilla CSS and ES6 modules? Browser support for import maps is around, but its nothing I would build a production application on. And god help if you if you work in a context that requires support for older browsers.

Maybe in 5 years this will be a practical approach, but there's a reason that old ways of doing thing hang around: they're well-documented and reliable.

[coddle-hark]

I mean, people ARE doing it, and like I said it's mature enough to be the default way to build Rails apps. There's tradeoffs, no doubt, but this is absolutely a valid, productive way to write (certain types of) web apps.