Keep Node.js ESM packages working when consumers rebundle them as CommonJS

[dario-piotrowicz]

Node.js-targeted ESM bundles now provide a real require implementation for bundled CommonJS dependencies. This avoids downstream patches for dynamic require calls and keeps the packages usable when a consumer rebundles them to CommonJS.

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• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because: clear build output change
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: build output change

A picture of a cute animal (not mandatory, but encouraged)

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[changeset-bot]

🦋 Changeset detected

Latest commit: fe36d81

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 8 packages

Name	Type
@cloudflare/autoconfig	Patch
@cloudflare/codemods	Patch
@cloudflare/deploy-helpers	Patch
@cloudflare/workers-auth	Patch
@cloudflare/workers-utils	Patch
@cloudflare/remote-bindings	Patch
@cloudflare/cli-shared-helpers	Patch
@cloudflare/containers-shared	Patch

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[workers-devprod]

Codeowners approval required for this PR:

• @cloudflare/cloudchamber
• ✅ @cloudflare/wrangler

Show detailed file reviewers

• packages/containers-shared/tsup.config.ts: [@cloudflare/cloudchamber]

[devin-ai-integration]

Devin Review found 2 potential issues.

[ask-bonk]

@cloudflare/workers-utils exposes dist/browser.mjs through its browser export condition. This banner is emitted into that entry point too, so browser consumers now receive a static node:module import and browser bundlers reject the package before constructWranglerConfig can be used. Build src/browser.ts separately without the Node-only banner, and keep the banner on the remaining Node entries.

export default defineConfig(() => [
	{
		treeshake: true,
		keepNames: true,
		entry: ["src/browser.ts"],
		platform: "node",
		format: "esm",
		dts: true,
		outDir: "dist",
		tsconfig: "tsconfig.json",
		metafile: true,
		sourcemap: process.env.SOURCEMAPS !== "false",
		define: {
			"process.env.NODE_ENV": `'${"production"}'`,
		},
		external: ["@cloudflare/*", "vitest", ...EXTERNAL_DEPENDENCIES],
	},
	{
		treeshake: true,
		keepNames: true,
		entry: [
			"src/index.ts",
			"src/prometheus-metrics.ts",
			"src/test-helpers/index.ts",
			"src/compliance.ts",
			"src/compatibility-date.ts",
			"src/docker-path.ts",
			"src/errors.ts",
			"src/fs-helpers.ts",
			"src/global-wrangler-config-path.ts",
			"src/local-env.ts",
			"src/zod-format.ts",
		],
		platform: "node",
		banner: {
			js: 'import { createRequire as __createRequire } from "node:module"; const require = __createRequire(typeof __filename === "string" ? __filename : import.meta.url);',
		},
		format: "esm",
		dts: true,
		outDir: "dist",
		tsconfig: "tsconfig.json",
		metafile: true,
		sourcemap: process.env.SOURCEMAPS !== "false",
		define: {
			"process.env.NODE_ENV": `'${"production"}'`,
		},
		external: ["@cloudflare/*", "vitest", ...EXTERNAL_DEPENDENCIES],
	},
]);

[ask-bonk]

I'm Bonk, and I've done a quick review of your PR.

PR #15870 adds CommonJS require support to Node-targeted ESM bundles.

1. P1: workers-utils now breaks its browser export by injecting node:module; suggested fix posted.

github run

[pkg-pr-new]

@cloudflare/autoconfig

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@cloudflare/build-output-utils

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@cloudflare/codemods

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@cloudflare/config

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@cloudflare/containers-shared

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create-cloudflare

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@cloudflare/deploy-helpers

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@cloudflare/kv-asset-handler

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miniflare

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@cloudflare/pages-functions

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@cloudflare/pages-shared

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@cloudflare/runtime-types

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@cloudflare/unenv-preset

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@cloudflare/vite-plugin

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@cloudflare/vitest-plugin

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@cloudflare/workers-auth

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@cloudflare/workers-editor-shared

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@cloudflare/workers-utils

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wrangler

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commit: fe36d81

[NuroDev]

Codeowners Bypass

[workers-devprod]

Codeowners reviews satisfied