> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usebruno.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Whitelisting Modules

The scripts can use both [external libraries](/testing/script/external-libraries) (via package.json and npm install) and certain [built-in](/testing/script/inbuilt-libraries) modules in Node.js (like fs, path, etc.). However, for security reasons, not all built-in Node.js modules are made accessible by default in Bruno scripts.

## Why Whitelisting

Bruno requires you to explicitly enable (whitelist) modules before they can be used in scripts due to security reasons. The whitelisting process ensures that only the modules you specifically choose to enable will be available to your scripts.

You can manually enable or whitelist these modules by editing your `bruno.json` file. Make sure to add the `script` section to the file.

```json copy filename="bruno.json" showLineNumbers {6-11} theme={null}
{
  "version": "1",
  "name": "collection_name",
  "type": "collection",
  "ignore": ["node_modules", ".git"],
  "scripts": {
    "moduleWhitelist": ["child_process"],
    "filesystemAccess": {
      "allow": true
    }
  }
}
```

<Warning>
  `filesystemAccess` is required for reading and writing files, especially for
  modules that depend on it.
</Warning>

### Whitelisting Multiple Modules

If you need to use multiple built-in or trusted third-party modules in your Bruno script, you can whitelist them by adding them to the `moduleWhitelist` array. For example:

```json copy filename="bruno.json" showLineNumbers theme={null}
 "scripts": {
      "moduleWhitelist": ["crypto", "jwt", "child_process"],
      "filesystemAccess": {
        "allow": true
      }
    }
```

Only whitelist modules that you trust and that are necessary for your script to function properly.