What versions & operating system are you using?

System:
OS: Windows 11 10.0.26100
CPU: (32) x64 AMD Ryzen 9 9950X 16-Core Processor
Memory: 12.45 GB / 31.06 GB
Binaries:
Node: 24.12.0 - C:\Program Files\nodejs\node.EXE
Yarn: 1.22.22 - C:\Program Files\nodejs\yarn.CMD
npm: 11.6.2 - C:\Program Files\nodejs\npm.CMD
pnpm: 10.28.0 - C:\Program Files\nodejs\pnpm.CMD
bun: 1.3.3 - C:\Users\green\AppData\Local\Microsoft\WinGet\Links\bun.EXE
Deno: 2.6.4 - C:\Users\green\AppData\Local\Microsoft\WinGet\Links\deno.EXE
npmPackages:
@cloudflare/vite-plugin: ^1.21.0 => 1.21.0
wrangler: ^4.59.2 => 4.59.2

Please provide a link to a minimal reproduction

https://github.com/sapphi-red-repros/vite8-cloudflare-plugin-node

Describe the Bug

require(node builtin module) (e.g. require('crypto')) does not work with vite-plugin even if nodejs_compat is enabled when using Vite 8.

The output with Vite 7 is like:

import { EventEmitter } from "node:events";
import require$$0 from "buffer";
import require$$3 from "stream";
import require$$5 from "util";
import require$$1 from "crypto";

// uses require$$\d

But the output with Vite 8 is like:

var __require = /* @__PURE__ */ ((x) => typeof require !== "undefined" ? require : typeof Proxy !== "undefined" ? new Proxy(x, { get: (a, b) => (typeof require !== "undefined" ? require : a)[b] }) : x)(function(x) {
	if (typeof require !== "undefined") return require.apply(this, arguments);
	throw Error("Calling `require` for \"" + x + "\" in an environment that doesn't expose the `require` function.");
});
// ....
var require_safe_buffer = /* @__PURE__ */ __commonJSMin(((exports, module) => {
	var buffer = __require("buffer");
	var Buffer = buffer.Buffer;

This difference comes from the fact that Rolldown does not covert external require to an import to avoid semantics change (docs).

Since CF workers does not have require defined, this __require throws an error when called (Calling `require` for "buffer" in an environment that doesn't expose the `require` function.).

While users can use the esmExternalRequirePlugin like

import { defineConfig } from 'vite'
import react from '@vitejs/plugin-react'
import { esmExternalRequirePlugin } from 'vite'
import { builtinModules } from 'node:module'
import { cloudflare } from '@cloudflare/vite-plugin'

// https://vite.dev/config/
export default defineConfig({
  plugins: [
    react(),
    cloudflare(),
    esmExternalRequirePlugin({
      external: [/^node:/, ...builtinModules],
    }),
  ],
})

, it is not obvious why it's safe to convert require to import for users. This may also break the unenv support.

I think Vite doesn't have enough knowledge to handle this automatically on Vite side, but I'm open to doing so if possible.

Please provide any relevant error logs

No response