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

> coveralls@3.1.1 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

takes json-cov output into stdin and POSTs to coveralls.io

Last verified Sep 9, 2026 against coveralls@3.1.1.

coveralls ships CommonJS only. require("coveralls") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=6. import "coveralls" 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("coveralls") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=6.
2. From ES modules use the default import: import coveralls from "coveralls"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: no types are available for coveralls; declare the module yourself if you need them.

## Facts

- Latest: 3.1.1 (Jun 29, 2021)
- Module format: CommonJS
- Last CommonJS version: 3.1.1
- TypeScript types: none
- Node engines: >=6
- Weekly downloads: 614K
- License: BSD-2-Clause

## Runtime test results for coveralls@3.1.1

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

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

ES modules:

```js
import coveralls from "coveralls";
```

CommonJS:

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

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (71 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 2.0.6 – 3.1.1 | CommonJS | Apr 8, 2013 |

## Frequently asked

**Is coveralls ESM-only?**

coveralls@3.1.1 is a CommonJS package. coveralls ships CommonJS only. require("coveralls") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=6. import "coveralls" 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 coveralls with ES module syntax?**

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

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

**Does coveralls ship TypeScript types?**

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

## Links

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

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