# Is extend ESM-only? Can you require() it?

> extend@3.0.2 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Port of jQuery.extend for node.js and the browser

Last verified Sep 9, 2026 against extend@3.0.2.

extend ships CommonJS only. require("extend") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "extend" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

## What to do

1. require("extend") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun.
2. From ES modules use the default import: import extend from "extend"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/extend

## Facts

- Latest: 3.0.2 (Jul 19, 2018)
- Module format: CommonJS
- Last CommonJS version: 3.0.2
- TypeScript types: @types/extend
- Node engines: not declared
- Weekly downloads: 68.3M
- License: MIT

## Runtime test results for extend@3.0.2

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

| Runtime | require("extend") | import "extend" |
|---|---|---|
| Node.js 18 | works | works |
| Node.js 20 | works | works |
| Node.js 22 | works | works |
| Node.js 24 | works | works |
| Node.js 26 | works | works |
| Bun 1.4.0 | works | works |

## How to import extend

ES modules:

```js
import extend from "extend";
```

CommonJS:

```js
const extend = require("extend");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (13 versions; the newest 13 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 3.0.2 | CommonJS | May 14, 2011 |

## Frequently asked

**Is extend ESM-only?**

extend@3.0.2 is a CommonJS package. extend ships CommonJS only. require("extend") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "extend" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

**Can I import extend with ES module syntax?**

Yes. import extend from "extend" works in Node.js and Bun because they support importing CommonJS modules. Named imports work only when Node.js can statically detect the exports.

**Does extend work in Bun?**

Yes. import "extend" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does extend ship TypeScript types?**

Not bundled. Install the community types with "npm install -D @types/extend".

## Links

- [extend on npm](https://www.npmjs.com/package/extend)
- [Source repository](https://github.com/justmoon/node-extend)
- [HTML version](https://canirequire.com/package/extend/)
- [JSON version](https://canirequire.com/package/extend.json)

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