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

> define-properties@1.2.1 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Define multiple non-enumerable properties at once. Uses `Object.defineProperty` when available; falls back to standard assignment in older engines.

Last verified Sep 9, 2026 against define-properties@1.2.1.

define-properties ships CommonJS only. require("define-properties") 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 "define-properties" 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("define-properties") 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 defineProperties from "define-properties"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/define-properties

## Facts

- Latest: 1.2.1 (Sep 13, 2023)
- Module format: CommonJS
- Last CommonJS version: 1.2.1
- TypeScript types: @types/define-properties
- Node engines: >= 0.4
- Weekly downloads: 90.7M
- License: MIT

## Runtime test results for define-properties@1.2.1

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

| Runtime | require("define-properties") | import "define-properties" |
|---|---|---|
| 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 define-properties

ES modules:

```js
import defineProperties from "define-properties";
```

CommonJS:

```js
const defineProperties = require("define-properties");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (10 versions; the newest 10 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 1.2.1 | CommonJS | Jan 4, 2015 |

## Frequently asked

**Is define-properties ESM-only?**

define-properties@1.2.1 is a CommonJS package. define-properties ships CommonJS only. require("define-properties") 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 "define-properties" 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 define-properties with ES module syntax?**

Yes. import defineProperties from "define-properties" 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 define-properties work in Bun?**

Yes. import "define-properties" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does define-properties ship TypeScript types?**

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

## Links

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

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