[_heimdall]

In my experience, the most frequently missed benefit of HTMX, and server rendering in general, is that you actually control the hardware your frontend is rendered on.

If and when you find performance issues in production you can much more easily reproduce and fix it when conversion from data to HTML is done on a server and infrastructure that you own.

Trying to track down render performance issues with client side rendering is a huge pain that more often then not leads to a bug being chalked up to "can't reproduce" or blaming the user's device/browser/network. Tracking down rendering performance issues with server rendering almost always leads to optimizing database queries or reworking your internal infrastructure.

[winrid]

Hmm. But if you can impersonate users and see what they see, doesn't that let you see the problem?

Also you're describing database queries and architecture as being a potential issue. Won't APIs be just as slow for the same reasons?

[_heimdall]

Impersonating users only gives you their data, with client rendering you may need their device and network conditions to reproduce a bug.

If the bug is in an API you're really just tracking down an issue in your server rendering. When an issue is in client rendering it's after the API response. It could be anything from a network delay that times out some client logic to a corner case that causes a re-render loop or a specific JS performance difference on a specific device with a specific browser version.

My point is just that you don't own the actual hardware or network when rendering UI on the client. That's not to say you should never use client rendering, it is a good fit for some use cases, but I've always found debugging rendering or performance bugs a huge pain compared to server rendering.

[winrid]

I don't use React - I like just using the DOM - so personally I rarely have client side performance issues (unless I do something really dumb).

[wordofx]

No because you’re not using their computer to reproduce the issue.

[winrid]

I found keeping an old machine or two around is enough. Old laptops are pretty much free.

Generally frontend performance problems are easy to diagnose, easy enough that that's not a consideration when architecting an app in most cases. If your React UI is taking 30% of your dev PC CPU then that's pretty obvious that it's gonna be slow on an average laptop from Walmart with a 5k passmark score.