[WorldMaker]

I got into some details on how I do light-weight apps (especially during development) without bundling in a nearby comment as well: https://news.ycombinator.com/item?id=39564986

To resummarize: sometimes it is fine to prune and ship node_modules to your web server, you can use import maps to handle "node-style 'bare' imports", and you may only need to "spot bundle" to ESM a single dependent library or two that doesn't ship ESM that will directly work in the browser (which should be a decreasing list).

After that it's a matter of using your browser's Dev Tools to tell you what your performance looks like and where your bottlenecks are. That can tell you a lot to help you determine if you really need to bundle more of your site/app or if you can spot-bundle/adjust an import map for just a specific sub-graph. With HTTP/2 and HTTP/3 the "per-file" "penalty" is a lot less, though still somewhat exists. Even some properly configured HTTP/1.1 servers it is not always as bad as history tells us it was (properly configured HTTP/1.1 did support some connection sharing). About the only remaining thing a bundle might buy you on HTTP/2+ is maybe better behavior with compression on the bundle as a single whole, but even that isn't a given because Brotli's dictionary was designed to work at the whole connection level and that's often the default compression in HTTP/2+. But again, your conditions may vary based on your real code and the specific servers and browsers you need to support, so leverage your browser Dev Tools and check the real numbers.