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

> yaml@2.9.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

JavaScript parser and stringifier for YAML

Last verified Sep 9, 2026 against yaml@2.9.0.

yaml ships CommonJS only. require("yaml") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 14.6. import "yaml" 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("yaml") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 14.6.
2. From ES modules use the default import: import yaml from "yaml"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 2.9.0 (May 11, 2026)
- Module format: CommonJS
- Last CommonJS version: 2.9.0
- TypeScript types: bundled
- Node engines: >= 14.6
- Weekly downloads: 176.1M
- License: ISC

## Runtime test results for yaml@2.9.0

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

| Runtime | require("yaml") | import "yaml" |
|---|---|---|
| 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 yaml

ES modules:

```js
import yaml from "yaml";
```

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (68 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 2.9.0 | CommonJS | Sep 19, 2018 |

## Frequently asked

**Is yaml ESM-only?**

yaml@2.9.0 is a CommonJS package. yaml ships CommonJS only. require("yaml") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 14.6. import "yaml" 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 yaml with ES module syntax?**

Yes. import yaml from "yaml" 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 yaml work in Bun?**

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

**Does yaml ship TypeScript types?**

Yes. yaml bundles its own type declarations; no @types package is needed.

## Links

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

---

For scripts and AI agents: any package is at https://canirequire.com/package/<name>/index.md (Markdown) or https://canirequire.com/package/<name>.json (JSON); the site index is https://canirequire.com/llms.txt. Fetch the URL directly; no search needed.