Next.js build errorNext.js: “The edge runtime does not support Node.js 'crypto' module”

Why the module is rejected, and the fix

1. 01

   Middleware or an Edge route uses a Node.js API

   “The code in your Proxy or your Edge API Routes is using a feature from Node.js runtime. However, the Edge Runtime does not support Node.js APIs and globals.” Next.js, Using Node.js Modules in Edge Runtime

   Code that runs on the Edge Runtime can only use Web APIs. Importing crypto, fs, a Node-only JWT or database library, or anything that pulls one in, breaks the build or the request. In next dev, the console and the browser name the file that imports the module.

2. 02

   Swap the Node API for a Web API

   “For example, you might replace the Node.js crypto module with the Web Crypto API.” Next.js, Using Node.js Modules in Edge Runtime

   For hashing or signing, use crypto.subtle, which works on Edge and in browsers. For JWTs, use a library built on Web Crypto, such as jose, in place of jsonwebtoken. Keep database calls out of middleware and do them in a route handler or server component that runs on Node.js.

   // works on the Edge Runtime
   const data = new TextEncoder().encode(token);
   const digest = await crypto.subtle.digest('SHA-256', data);

3. 03

   Next.js 15.5 and later: run middleware on Node.js

   “As of v15.5, we have support for using the Node.js runtime. To enable, in your middleware file, set the runtime to nodejs in the config object” Next.js, middleware.js (Next.js 15)

   If the code really needs Node.js, switch the runtime. On Next.js 15.5, middleware still defaults to Edge: add the config below to middleware.ts. On Next.js 16, rename middleware to proxy, which runs on Node.js with no config; the codemod npx @next/codemod@canary middleware-to-proxy . does the rename. Route handlers that set runtime = 'edge' are not changed by the rename; remove that line if they need Node.js.

   // middleware.ts on Next.js 15.5
   export const config = {
     runtime: 'nodejs',
   };

4. 04

   Or drop the import from the Edge file

   “This module must be avoided: either by not importing it, or by replacing it with a polyfill.” Next.js, Using Node.js Modules in Edge Runtime

   Sometimes the Node module comes in through a shared helper file that middleware imports for one small function. Split that helper so the Edge file only imports what it needs, or move the work out of middleware.

Checked against the vendor’s docs on November 7, 2026: Next.js: Using Node.js Modules in Edge Runtime; Next.js: proxy.js file convention (runtime and version history); Next.js 15: middleware.js (Node.js runtime from v15.5); Next.js: upgrading to version 16 (middleware to proxy).

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