# Is react-app-polyfill ESM-only? Can you require() it?

> react-app-polyfill@3.0.0 has no importable main entry. No JavaScript entry point.

Polyfills for various browsers including commonly used language features

Last verified Sep 9, 2026 against react-app-polyfill@3.0.0.

react-app-polyfill does not expose a JavaScript entry point in package.json. It is likely a CLI, a stylesheet, a type-definition package, or an asset bundle, so require() and import are not the way to use it.

## What to do

1. Do not require() or import react-app-polyfill: it has no JavaScript entry point. Use it as a CLI (npx react-app-polyfill), a stylesheet, an asset, or a type-definition package as its README describes.
2. TypeScript: no types are available for react-app-polyfill; declare the module yourself if you need them.

## Facts

- Latest: 3.0.0 (Dec 14, 2021)
- Module format: No JS entry point
- Last CommonJS version: n/a
- TypeScript types: none
- Node engines: >=14
- Weekly downloads: 2.1M
- License: MIT

## Runtime test results for react-app-polyfill@3.0.0

Installed and executed on Sep 9, 2026 with require("react-app-polyfill") from a CommonJS file and import "react-app-polyfill" from an ES module.

| Runtime | require("react-app-polyfill") | import "react-app-polyfill" |
|---|---|---|
| Node.js 18 | fails (MODULE_NOT_FOUND) | fails (ERR_MODULE_NOT_FOUND) |
| Node.js 20 | fails (MODULE_NOT_FOUND) | fails (ERR_MODULE_NOT_FOUND) |
| Node.js 22 | fails (MODULE_NOT_FOUND) | fails (ERR_MODULE_NOT_FOUND) |
| Node.js 24 | fails (MODULE_NOT_FOUND) | fails (ERR_MODULE_NOT_FOUND) |
| Node.js 26 | fails (MODULE_NOT_FOUND) | fails (ERR_MODULE_NOT_FOUND) |
| Bun 1.4.0 | fails (Error) | fails (Error) |

## How to import react-app-polyfill

ES modules:

```js
import * as reactAppPolyfill from "react-app-polyfill";
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (17 versions; the newest 17 shown).

| Versions | Format | First published |
|---|---|---|
| 0.0.0 – 3.0.0 | No JS entry point | Sep 25, 2018 |

## Frequently asked

**Is react-app-polyfill ESM-only?**

react-app-polyfill@3.0.0 has no importable main entry. react-app-polyfill does not expose a JavaScript entry point in package.json. It is likely a CLI, a stylesheet, a type-definition package, or an asset bundle, so require() and import are not the way to use it.

**Does react-app-polyfill work in Bun?**

Importing react-app-polyfill failed in Bun 1.4.0 on Sep 9, 2026: error: Cannot find package 'react-app-polyfill' from '/Users/boat/Projects/top-seo/data/probe-work/react-app-polyfill/imp.mjs'

**Does react-app-polyfill ship TypeScript types?**

No. react-app-polyfill ships no type declarations and there is no @types package for it.

## Links

- [react-app-polyfill on npm](https://www.npmjs.com/package/react-app-polyfill)
- [Source repository](https://github.com/facebook/create-react-app)
- [HTML version](https://canirequire.com/package/react-app-polyfill/)
- [JSON version](https://canirequire.com/package/react-app-polyfill.json)

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