# Is @istanbuljs/schema ESM-only? Can you require() it?

> @istanbuljs/schema@0.1.6 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Schemas describing various structures used by nyc and istanbuljs

Last verified Sep 9, 2026 against @istanbuljs/schema@0.1.6.

@istanbuljs/schema ships CommonJS only. require("@istanbuljs/schema") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8. import "@istanbuljs/schema" 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("@istanbuljs/schema") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8.
2. From ES modules use the default import: import schema from "@istanbuljs/schema"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: no types are available for @istanbuljs/schema; declare the module yourself if you need them.

## Facts

- Latest: 0.1.6 (Apr 13, 2026)
- Module format: CommonJS
- Last CommonJS version: 0.1.6
- TypeScript types: none
- Node engines: >=8
- Weekly downloads: 44.0M
- License: MIT

## Runtime test results for @istanbuljs/schema@0.1.6

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

| Runtime | require("@istanbuljs/schema") | import "@istanbuljs/schema" |
|---|---|---|
| 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 @istanbuljs/schema

ES modules:

```js
import schema from "@istanbuljs/schema";
```

CommonJS:

```js
const schema = require("@istanbuljs/schema");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (6 versions; the newest 6 shown).

| Versions | Format | First published |
|---|---|---|
| 0.1.0 – 0.1.6 | CommonJS | Oct 5, 2019 |

## Frequently asked

**Is @istanbuljs/schema ESM-only?**

@istanbuljs/schema@0.1.6 is a CommonJS package. @istanbuljs/schema ships CommonJS only. require("@istanbuljs/schema") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=8. import "@istanbuljs/schema" 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 @istanbuljs/schema with ES module syntax?**

Yes. import schema from "@istanbuljs/schema" 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 @istanbuljs/schema work in Bun?**

Yes. import "@istanbuljs/schema" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does @istanbuljs/schema ship TypeScript types?**

No. @istanbuljs/schema ships no type declarations and there is no @types package for it.

## Links

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

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