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

> expect-type@1.4.0 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

[![CI](https://github.com/mmkal/expect-type/actions/workflows/ci.yml/badge.svg)](https://github.com/mmkal/expect-type/actions/workflows/ci.yml) ![npm](https://img.shields.io/npm/dt/expect-type) [![X Follow](https://img.shields.io/twitter/follow/mmkal)](ht

Last verified Sep 9, 2026 against expect-type@1.4.0.

expect-type ships CommonJS only. require("expect-type") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=12.0.0. import "expect-type" 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("expect-type") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=12.0.0.
2. From ES modules use the default import: import expectType from "expect-type"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 1.4.0 (Jun 25, 2026)
- Module format: CommonJS
- Last CommonJS version: 1.4.0
- TypeScript types: bundled
- Node engines: >=12.0.0
- Weekly downloads: 78.4M
- License: Apache-2.0

## Runtime test results for expect-type@1.4.0

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

| Runtime | require("expect-type") | import "expect-type" |
|---|---|---|
| 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 expect-type

ES modules:

```js
import expectType from "expect-type";
```

CommonJS:

```js
const expectType = require("expect-type");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (54 versions; the newest 54 shown).

| Versions | Format | First published |
|---|---|---|
| 0.3.1 – 1.4.0 | CommonJS | Mar 3, 2020 |

## Frequently asked

**Is expect-type ESM-only?**

expect-type@1.4.0 is a CommonJS package. expect-type ships CommonJS only. require("expect-type") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=12.0.0. import "expect-type" 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 expect-type with ES module syntax?**

Yes. import expectType from "expect-type" 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 expect-type work in Bun?**

Yes. import "expect-type" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does expect-type ship TypeScript types?**

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

## Links

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

---

For scripts and AI agents: any package is at https://canirequire.com/package/<name>/index.md (Markdown) or https://canirequire.com/package/<name>.json (JSON); the site index is https://canirequire.com/llms.txt. Fetch the URL directly; no search needed.