How I Built a Website Health Scanner Inside Cloudflare Workers (And the Constraints I Hit)

I wanted one tool instead of opening four browser tabs every time I launched a website. PageSpeed Insights for performance. SecurityHeaders.com for security headers. Manual checks for meta tags and Open Graph. A separate accessibility checker. It was tedious, and I kept forgetting steps. So I built WebPulse — a scanner that runs performance, SEO, security, and accessibility checks in a single request. Here's what I learned building it on Cloudflare Workers. The Stack Cloudflare Workers — edge runtime, 330+ locations worldwide Hono — lightweight router that runs perfectly on Workers D1 — Cloudflare's SQLite-at-the-edge database TypeScript — because I like catching bugs before runtime Constraint #1: No DOM API The biggest surprise: Cloudflare Workers don't have a DOM. No document.querySelector , no DOMParser , nothing. Most website scanners run in Node.js or a headless browser where you can do: const dom = new DOMParser (). parseFromString ( html , ' text/html ' ); const title = dom . qu