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

> signal-exit@4.1.0 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

when you want to fire an event no matter how a process exits.

Last verified Sep 9, 2026 against signal-exit@4.1.0.

signal-exit publishes both a CommonJS entry and a native ESM entry (ESM added in 4.0.0). require("signal-exit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=14. import "signal-exit" works alongside it.

## What to do

1. Nothing to change. require("signal-exit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=14. import * as signalExit from "signal-exit" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 4.1.0 (Jul 29, 2023)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 4.1.0
- Native ESM since: 4.0.0
- TypeScript types: bundled
- Node engines: >=14
- Weekly downloads: 198.9M
- License: ISC

## Runtime test results for signal-exit@4.1.0

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

| Runtime | require("signal-exit") | import "signal-exit" |
|---|---|---|
| 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 signal-exit

ES modules:

```js
import * as signalExit from "signal-exit";
```

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

CommonJS:

```js
const signalExit = require("signal-exit");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (23 versions; the newest 23 shown).

| Versions | Format | First published |
|---|---|---|
| 4.0.0 – 4.1.0 | Dual (CommonJS + ESM) | Apr 16, 2023 |
| 1.0.0 – 3.0.7 | CommonJS | May 16, 2015 |

## Frequently asked

**Is signal-exit ESM-only?**

signal-exit@4.1.0 ships CommonJS and ESM builds. signal-exit publishes both a CommonJS entry and a native ESM entry (ESM added in 4.0.0). require("signal-exit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=14. import "signal-exit" works alongside it.

**Can I require signal-exit?**

Yes. signal-exit ships a CommonJS entry alongside the native ESM entry. require("signal-exit") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=14.

**Does signal-exit work in Bun?**

Yes. import "signal-exit" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does signal-exit ship TypeScript types?**

Yes. signal-exit bundles its own type declarations; no @types package is needed.

## Links

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

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