# Is @aws-sdk/core ESM-only? Can you require() it?

> @aws-sdk/core@3.977.9 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

Core functions & classes shared by multiple AWS SDK clients.

Last verified Sep 9, 2026 against @aws-sdk/core@3.977.9.

@aws-sdk/core publishes both a CommonJS entry and a native ESM entry (ESM added in 3.576.0). require("@aws-sdk/core") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=20.0.0. import "@aws-sdk/core" works alongside it.

## What to do

1. Nothing to change. require("@aws-sdk/core") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=20.0.0. import * as core from "@aws-sdk/core" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 3.977.9 (Aug 21, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 3.977.9
- Native ESM since: 3.576.0
- TypeScript types: bundled
- Node engines: >=20.0.0
- Weekly downloads: 81.1M
- License: Apache-2.0

## Runtime test results for @aws-sdk/core@3.977.9

Installed and executed on Sep 9, 2026 with require("@aws-sdk/core") from a CommonJS file and import "@aws-sdk/core" from an ES module.

| Runtime | require("@aws-sdk/core") | import "@aws-sdk/core" |
|---|---|---|
| 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 @aws-sdk/core

ES modules:

```js
import * as core from "@aws-sdk/core";
```

Namespace import shown because the ESM entry may have no default export; use named imports for what it exports.

CommonJS:

```js
const core = require("@aws-sdk/core");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (230 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 3.973.13 – 3.977.9 | Dual (CommonJS + ESM) | Feb 24, 2026 |

## Frequently asked

**Is @aws-sdk/core ESM-only?**

@aws-sdk/core@3.977.9 ships CommonJS and ESM builds. @aws-sdk/core publishes both a CommonJS entry and a native ESM entry (ESM added in 3.576.0). require("@aws-sdk/core") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=20.0.0. import "@aws-sdk/core" works alongside it.

**Can I require @aws-sdk/core?**

Yes. @aws-sdk/core ships a CommonJS entry alongside the native ESM entry. require("@aws-sdk/core") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=20.0.0.

**Does @aws-sdk/core work in Bun?**

Yes. import "@aws-sdk/core" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does @aws-sdk/core ship TypeScript types?**

Yes. @aws-sdk/core bundles its own type declarations; no @types package is needed.

## Links

- [@aws-sdk/core on npm](https://www.npmjs.com/package/@aws-sdk/core)
- [Source repository](https://github.com/aws/aws-sdk-js-v3)
- [HTML version](https://canirequire.com/package/@aws-sdk/core/)
- [JSON version](https://canirequire.com/package/@aws-sdk/core.json)

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