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

> jest-circus@30.5.1 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

[type-definitions]: https://github.com/jestjs/jest/blob/main/packages/jest-types/src/Circus.ts

Last verified Sep 9, 2026 against jest-circus@30.5.1.

jest-circus publishes both a CommonJS entry and a native ESM entry (ESM added in 30.0.0). require("jest-circus") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0. import "jest-circus" works alongside it.

## What to do

1. Nothing to change. require("jest-circus") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0. import * as jestCircus from "jest-circus" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 30.5.1 (Sep 1, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 30.5.1
- Native ESM since: 30.0.0
- TypeScript types: bundled
- Node engines: ^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0
- Weekly downloads: 41.9M
- License: MIT

## Runtime test results for jest-circus@30.5.1

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

| Runtime | require("jest-circus") | import "jest-circus" |
|---|---|---|
| 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 jest-circus

ES modules:

```js
import * as jestCircus from "jest-circus";
```

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

CommonJS:

```js
const jestCircus = require("jest-circus");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (155 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 30.0.0 – 30.5.1 | Dual (CommonJS + ESM) | Jun 10, 2025 |
| 27.2.4 – 29.7.0 | CommonJS | Sep 29, 2021 |

## Frequently asked

**Is jest-circus ESM-only?**

jest-circus@30.5.1 ships CommonJS and ESM builds. jest-circus publishes both a CommonJS entry and a native ESM entry (ESM added in 30.0.0). require("jest-circus") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0. import "jest-circus" works alongside it.

**Can I require jest-circus?**

Yes. jest-circus ships a CommonJS entry alongside the native ESM entry. require("jest-circus") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0.

**Does jest-circus work in Bun?**

Yes. import "jest-circus" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does jest-circus ship TypeScript types?**

Yes. jest-circus bundles its own type declarations; no @types package is needed.

## Links

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

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