# unicorn/prefer-module

> Require ES modules instead of CommonJS

`require`, `module`, `exports`, `__filename` and `__dirname` are CommonJS. In an ES module, Node.js throws a `ReferenceError` for them, and bundlers can't tree-shake a `require()` the way they do an `import`.

The rule reports those five globals. It also reports the `"use strict"` directive, because an ES module is always strict.

Files that end in `.cjs` aren't checked.

{/* Generated by src/codegen/lint-rule-docs.ts. Do not edit this section. */}

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"unicorn/prefer-module" = "error" # or "warn"
```

{/* End of the generated section. */}

## Examples

Reported:

{/* bad {"count": 4} */}
```js
"use strict";

const path = require("path");

module.exports = path.join(__dirname, "config.json");
```

Not reported:

{/* good */}
```js
import path from "node:path";

export default path.join(import.meta.dirname, "config.json");
```

A local variable with one of those names isn't reported:

{/* good */}
```js
export function load(require) {
  return require("./plugin.js");
}
```

Nothing is reported in a `.cjs` file:

{/* good {"filename": "config.cjs"} */}
```js
module.exports = require("./defaults.json");
```

## When not to use it

Turn it off in a package that's still CommonJS, or name the CommonJS files `.cjs`.