The Hidden Performance Costs of Overbuilt Websites
Modern websites are slower than they were five years ago — despite faster hardware and better networks. The culprit is almost always the same: too much JavaScript, too early.
There's a paradox at the heart of modern web development: we have faster devices, faster networks, and better tooling than at any point in history — and yet the median web page is heavier and slower than it was in 2019.
The JavaScript Problem
The single biggest contributor to slow websites today is JavaScript bundle size. Not images. Not fonts. JavaScript. When a browser downloads a 400KB JavaScript bundle, it has to parse it, compile it, and execute it before the page becomes interactive — and this CPU work happens on the device, not on a server.
What "Fast" Actually Means in 2026
Google's Core Web Vitals give us a clear target: LCP under 2.5 seconds, FID under 100ms, CLS under 0.1. But these numbers mean very little to clients. What matters is conversion rate. Studies consistently show that a 100ms improvement in page load time correlates with a 1% lift in conversions.
The Minimal Viable Stack
For most marketing websites, the optimal stack is simpler than you think: semantic HTML, scoped CSS, and a minimal vanilla JS layer for interactions. No framework. No build system. Ship less, load faster, convert more.
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