# Is object.assign ESM-only? Can you require() it?

> object.assign@4.1.7 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

ES6 spec-compliant Object.assign shim. From https://github.com/es-shims/es6-shim

Last verified Sep 9, 2026 against object.assign@4.1.7.

object.assign ships CommonJS only. require("object.assign") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4. import "object.assign" 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("object.assign") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4.
2. From ES modules use the default import: import objectAssign from "object.assign"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/object.assign

## Facts

- Latest: 4.1.7 (Dec 18, 2024)
- Module format: CommonJS
- Last CommonJS version: 4.1.7
- TypeScript types: @types/object.assign
- Node engines: >= 0.4
- Weekly downloads: 85.9M
- License: MIT

## Runtime test results for object.assign@4.1.7

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

| Runtime | require("object.assign") | import "object.assign" |
|---|---|---|
| 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 object.assign

ES modules:

```js
import objectAssign from "object.assign";
```

CommonJS:

```js
const objectAssign = require("object.assign");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (33 versions; the newest 33 shown).

| Versions | Format | First published |
|---|---|---|
| 0.1.0 – 4.1.7 | CommonJS | Mar 14, 2014 |

## Frequently asked

**Is object.assign ESM-only?**

object.assign@4.1.7 is a CommonJS package. object.assign ships CommonJS only. require("object.assign") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4. import "object.assign" 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 object.assign with ES module syntax?**

Yes. import objectAssign from "object.assign" 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 object.assign work in Bun?**

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

**Does object.assign ship TypeScript types?**

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

## Links

- [object.assign on npm](https://www.npmjs.com/package/object.assign)
- [Source repository](https://github.com/ljharb/object.assign)
- [HTML version](https://canirequire.com/package/object.assign/)
- [JSON version](https://canirequire.com/package/object.assign.json)

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