Sometimes I forget how much the browser can do for us

When I think about web performance, I usually think about things like bundle sizes, caching and rendering strategies. All important, and all topics that could easily turn into articles of their own.

But sometimes I go back to something much simpler: HTML.

A few attributes can help the browser decide when to load an image, how much space to reserve for it, and which file to choose. Less custom logic for me, more work for the browser. Seems fair.

I’ve been thinking about these details more since I started using AI tools. I can ask an agent to build a component and get something that looks good in minutes. But did it add image dimensions? Is the hero image being lazy-loaded? Is that tiny card downloading a massive image?

The agent might have thought about all of this. Or maybe not.…