A CDN caches files; edge computing runs functions on the same boxes — routing, A/B bucketing, geolocation headers, auth checks — in milliseconds from the user. The request never travels home, so the response never pays for the distance.
The constraint is the runtime: edge functions are short-lived, small, and limited in what they can touch — no long connections, no giant dependencies. Right-sized work belongs there: a geo-redirect, a header rewrite, a light personalization. The heavy lifting still lives at the origin, where the data is.
Related terms
CDN
Content delivery network — copies of your assets on servers near your visitors, so 'far away' stops meaning 'slow'.
Server-side rendering (SSR)
Generating the page's HTML on the server per request — the browser gets a complete page, not a loader and a promise.
LCP (Largest Contentful Paint)
The moment the biggest piece of content in the viewport finishes rendering — in practice, when the page looks loaded.
The bench this belongs to
Web performanceA rebuild that loads on a phone on mobile data, in the country your customers are actually in. Core Web Vitals are the measurement, revenue is the point.
