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

> rfdc@1.4.1 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

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Last verified Sep 9, 2026 against rfdc@1.4.1.

rfdc ships CommonJS only. require("rfdc") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "rfdc" 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("rfdc") 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 rfdc from "rfdc"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 1.4.1 (Jun 12, 2024)
- Module format: CommonJS
- Last CommonJS version: 1.4.1
- TypeScript types: bundled
- Node engines: not declared
- Weekly downloads: 46.8M
- License: MIT

## Runtime test results for rfdc@1.4.1

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

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

ES modules:

```js
import rfdc from "rfdc";
```

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (14 versions; the newest 14 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 1.4.1 | CommonJS | May 19, 2018 |

## Frequently asked

**Is rfdc ESM-only?**

rfdc@1.4.1 is a CommonJS package. rfdc ships CommonJS only. require("rfdc") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. import "rfdc" 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 rfdc with ES module syntax?**

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

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

**Does rfdc ship TypeScript types?**

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

## Links

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

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