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

> fs@0.0.1-security is a CommonJS package. CommonJS — require() works on every Node.js version we test.

This package name is not currently in use, but was formerly occupied by another package. To avoid malicious use, npm is hanging on to the package name, but loosely, and we'll probably give it to you if you want it.

Last verified Sep 9, 2026 against fs@0.0.1-security.

fs ships CommonJS only. require("fs") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "fs" 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("fs") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun.
2. From ES modules use the default import: import fs from "fs"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: no types are available for fs; declare the module yourself if you need them.

## Facts

- Latest: 0.0.1-security (Aug 23, 2016)
- Module format: CommonJS
- Last CommonJS version: 0.0.0
- TypeScript types: none
- Node engines: not declared
- Weekly downloads: 1.1M
- License: ISC

## Runtime test results for fs@0.0.1-security

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

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

ES modules:

```js
import fs from "fs";
```

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (2 versions; the newest 2 shown).

| Versions | Format | First published |
|---|---|---|
| 0.0.0 – 0.0.2 | CommonJS | Sep 12, 2014 |

## Frequently asked

**Is fs ESM-only?**

fs@0.0.1-security is a CommonJS package. fs ships CommonJS only. require("fs") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "fs" 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 fs with ES module syntax?**

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

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

**Does fs ship TypeScript types?**

No. fs ships no type declarations and there is no @types package for it.

## Links

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

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