canirequire › Dual (CommonJS + ESM) › js-yaml
Is js-yaml ESM-only? Can you require() it?
YAML 1.2 parser and serializer
Last verified Sep 9, 2026 against js-yaml@5.4.1. JSON
Dual (CommonJS + ESM) Dual package — both require() and import work
js-yaml publishes both a CommonJS entry and a native ESM entry (ESM added in 4.0.0). require("js-yaml") and import "js-yaml" both work on every supported Node.js version and in Bun.
Does js-yaml@5.4.1 actually load? Runtime test results
Installed and executed on Sep 9, 2026 with require("js-yaml") from a CommonJS file and import "js-yaml" from an ES module.
| Runtime | require("js-yaml") | import "js-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 | ✓ works | ✓ works |
How to import js-yaml
ES modules (import)
import jsYaml from "js-yaml";CommonJS (require)
const jsYaml = require("js-yaml");Module format by version
Derived from the type, main and exports fields of every stable release on npm (90 versions; the newest 60 shown).
| Versions | Format | First published |
|---|---|---|
| 4.0.0 – 5.4.1 | Dual (CommonJS + ESM) | Jan 3, 2021 |
| 3.2.2 – 3.15.2 | CommonJS | Sep 6, 2014 |
Frequently asked
Is js-yaml ESM-only?
js-yaml@5.4.1 ships CommonJS and ESM builds. js-yaml publishes both a CommonJS entry and a native ESM entry (ESM added in 4.0.0). require("js-yaml") and import "js-yaml" both work on every supported Node.js version and in Bun.
Can I require js-yaml?
Yes. js-yaml ships a CommonJS entry, so require("js-yaml") works on every Node.js version, alongside the native ESM entry for import.
Does js-yaml work in Bun?
Yes. import "js-yaml" loaded successfully in Bun 1.4 on Sep 9, 2026.
Does js-yaml ship TypeScript types?
Yes. js-yaml bundles its own type declarations; no @types package is needed.
Links
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