Edge Functions
Serverless functions that run on CDN servers closest to your users, reducing latency and enabling faster, personalized experiences.
What are Edge Functions?
Edge Functions are serverless functions that run on the CDN edge, meaning they execute on servers physically closer to your users instead of in one central data center.
They're basically serverless functions with a speed boost. Instead of your code running in us-east-1 and taking 200ms to respond to someone in Tokyo, it runs on a node near Tokyo and responds in 50ms.
Most builders use them for things like auth checks, A/B testing, or personalizing content without the round-trip to your main server. Popular on Vercel, Netlify, and Cloudflare Workers.
They have some limits compared to regular serverless functions. Smaller runtime, can't run heavy processing, and typically support JavaScript/TypeScript only. But for fast, lightweight logic at the edge, they're perfect.
Good to Know
Run on CDN nodes closest to users, typically reducing latency by 50-80%
Limited runtime compared to serverless functions - lightweight JavaScript/TypeScript only
No cold starts or minimal cold starts since they're already distributed globally
Best for auth, redirects, personalization, and A/B testing
Pricing is usually per request, starting around $0.50 per million requests
How Vibe Coders Use Edge Functions
Checking auth tokens before letting users hit your API
Serving different landing pages based on user location
Running A/B tests without adding JavaScript to your frontend
Redirecting users based on their device or browser
Frequently Asked Questions
Related Terms
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