What is Edge Computing?
Edge computing runs your logic closer to users. Instead of processing requests in a single data center, edge functions execute at CDN nodes worldwide — typically within 50ms of the user.
Next.js Middleware at the Edge
// middleware.tsimport { NextRequest, NextResponse } from "next/server";export function middleware(request: NextRequest) { const country = request.geo?.country || "US"; if (country === "DE") { return NextResponse.rewrite(new URL("/de" + request.nextUrl.pathname, request.url)); } const token = request.cookies.get("session"); if (!token && request.nextUrl.pathname.startsWith("/dashboard")) { return NextResponse.redirect(new URL("/login", request.url)); } return NextResponse.next();}export const config = { matcher: ["/((?!api|_next/static|_next/image|favicon.ico).*)"],};Edge vs Node.js Runtime
Edge: lower latency, smaller API surface, runs at CDN
Node.js: full API access, better for complex logic
Use edge for: redirects, rewrites, auth checks, geo-routing
Use Node.js for: database queries, file processing, complex API logic
Performance Impact
Moving authentication and routing logic to the edge can reduce TTFB by 50-200ms for users far from your origin server.