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

> synckit@0.11.13 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

Perform async work synchronously in Node.js using `worker_threads` with first-class TypeScript support.

Last verified Sep 9, 2026 against synckit@0.11.13.

synckit publishes both a CommonJS entry and a native ESM entry (ESM added in 0.4.0). require("synckit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.18.0 || >=16.0.0. import "synckit" works alongside it.

## What to do

1. Nothing to change. require("synckit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.18.0 || >=16.0.0. import * as synckit from "synckit" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 0.11.13 (May 28, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 0.11.13
- Native ESM since: 0.4.0
- TypeScript types: bundled
- Node engines: ^14.18.0 || >=16.0.0
- Weekly downloads: 45.3M
- License: MIT

## Runtime test results for synckit@0.11.13

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

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

ES modules:

```js
import * as synckit from "synckit";
```

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

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (54 versions; the newest 54 shown).

| Versions | Format | First published |
|---|---|---|
| 0.4.0 – 0.11.13 | Dual (CommonJS + ESM) | Aug 29, 2021 |
| 0.1.0 – 0.3.4 | CommonJS | Apr 26, 2021 |

## Frequently asked

**Is synckit ESM-only?**

synckit@0.11.13 ships CommonJS and ESM builds. synckit publishes both a CommonJS entry and a native ESM entry (ESM added in 0.4.0). require("synckit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.18.0 || >=16.0.0. import "synckit" works alongside it.

**Can I require synckit?**

Yes. synckit ships a CommonJS entry alongside the native ESM entry. require("synckit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.18.0 || >=16.0.0.

**Does synckit work in Bun?**

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

**Does synckit ship TypeScript types?**

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

## Links

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

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