How to Spy on Your Competitors' Tech Stack (Ethically)

Ever wondered what framework your competitor is using? Or what analytics tool that fast-growing startup runs? Every website leaks signals about its technology stack — through HTTP headers, JavaScript globals, meta tags, DNS records, and more. Here's how to detect it programmatically. The Manual Way (Tedious) You could open DevTools and look for clues: X-Powered-By: Express in response headers <meta name="generator" content="WordPress"> in HTML window.__NEXT_DATA__ in the console But this is slow and incomplete. You'd miss DNS-level signals (like Cloudflare), TLS certificate details, or deeply embedded analytics scripts. The API Way (Fast) I built TechDetect API — a single endpoint that scans all these layers automatically. curl "https://techdetect.dapdev.tech/detect?url=https://vercel.com" Real response: { "url" : "https://vercel.com" , "technologies" : [ { "name" : "Next.js" , "categories" : [ "JavaScript Framework" ], "confidence" : 0.7 , "detected_by" : [ "headers" , "html" ]}, { "n