Node Runtime vs Edge Runtime Tradeoffs
Choose between Node and Edge per-route based on cold starts, APIs available, and geographic latency.
Two Runtimes, One Route Handler
In Next.js 15, every Route Handler (app/api/.../route.ts) runs on one of two runtimes: the Node.js runtime (the default) or the Edge runtime.
- Node runtime — a full Node.js server. Access to all Node APIs, npm packages, file system, TCP sockets.
- Edge runtime — a lightweight V8-based environment (Web APIs only) that deploys to many locations close to your users.
You pick the runtime per route with a single export, so different endpoints in the same app can use different runtimes.
// app/api/hello/route.ts
import { NextResponse } from 'next/server';
// Opt this route into the Edge runtime
export const runtime = 'edge';
export async function GET() {
return NextResponse.json({ message: 'Hello from the Edge' });
}The Default Is Node
If you do not set runtime, the handler runs on the Node.js runtime. This is the safe default for most fullstack work because it supports your database drivers, ORMs (Prisma, Drizzle), and any npm library.
You only opt into Edge when its specific benefits (low latency, fast cold starts, geographic distribution) matter more than the APIs you'd give up.
// app/api/users/route.ts
import { NextResponse } from 'next/server';
import { db } from '@/lib/db'; // e.g. Prisma / Drizzle
// No runtime export => Node.js runtime (default)
export async function GET() {
const users = await db.user.findMany();
return NextResponse.json(users);
}