Edge functions are serverless functions that run on distributed servers located geographically closer to end-users. Instead of executing code on a centralized origin server, edge functions run at the edge of the network, providing faster response times and reduced latency.
Edge functions work through a simple process. When a user makes a request, it hits the nearest edge server in the network. The edge function executes locally on that server, processing the request without needing to contact the origin server. This results in reduced latency, lower server load, and a better overall user experience.
Edge functions have many practical use cases. They handle authentication and authorization, modify requests and responses, enable A B testing and personalization, manage caching and content optimization, detect bots for security, and handle redirects and URL rewriting. For example, user login verification can happen at the edge before the request reaches the main application, improving both security and performance.
Several major platforms provide edge function capabilities. Cloudflare Workers, Vercel Edge Functions, AWS Lambda at Edge, Fastly Compute at Edge, and Deno Deploy are among the popular providers. These platforms typically support JavaScript and TypeScript, offer global deployment across their networks, use pay-per-execution pricing models, and provide millisecond cold start times for optimal performance.
To summarize what we've learned about edge functions: They are serverless functions that run closer to users, providing faster response times. They enable various capabilities like authentication, caching, and request modification. Major platforms like Cloudflare, Vercel, and AWS provide these services. The main benefits include reduced latency and improved user experience, making them essential for modern web applications that require global performance.