# Install custom packages (/docs/quickstart/install-custom-packages)

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Related: [Connect LLMs to E2B](/docs/quickstart/connect-llms.md), [Upload & downloads files](/docs/quickstart/upload-download-files.md)

There are two ways to install custom packages in the E2B Sandbox.

1. [Create custom sandbox with preinstalled packages](#create-a-custom-sandbox).
2. [Install packages during the sandbox runtime](#install-packages-during-the-sandbox-runtime).

***

## Create a custom sandbox [#create-a-custom-sandbox]

Use this option if you know beforehand what packages you need in the sandbox.

<Note>
  Sandbox templates allow you to define custom sandboxes with preinstalled packages and configurations.
</Note>

### 1. Install the E2B SDK [#1-install-the-e2b-sdk]

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      </CodeBlockTabsTrigger>

      <CodeBlockTabsTrigger value="Python">
        Python
      </CodeBlockTabsTrigger>
    </CodeBlockTabsList>

    <CodeBlockTab value="JavaScript & TypeScript">
      ```bash  
      npm install e2b dotenv
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```bash  
      pip install e2b python-dotenv
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
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Create a `.env` file with your API key:

```bash
E2B_API_KEY=e2b_***
```

### 2. Create a template file [#2-create-a-template-file]

Define your custom template with the packages you need.

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      <CodeBlockTabsTrigger value="Python">
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      </CodeBlockTabsTrigger>
    </CodeBlockTabsList>

    <CodeBlockTab value="JavaScript & TypeScript">
      ```typescript  
      // template.ts
      import { Template } from 'e2b';

      export const template = Template()
        .fromTemplate("code-interpreter-v1")
        .pipInstall(['cowsay'])  // Install Python packages
        .npmInstall(['cowsay']);  // Install Node.js packages
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      # template.py
      from e2b import Template

      template = (
          Template()
          .from_template("code-interpreter-v1")
          .pip_install(['cowsay'])  # Install Python packages
          .npm_install(['cowsay'])  # Install Node.js packages
      )
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
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### 3. Create a build script [#3-create-a-build-script]

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      <CodeBlockTabsTrigger value="Python">
        Python
      </CodeBlockTabsTrigger>
    </CodeBlockTabsList>

    <CodeBlockTab value="JavaScript & TypeScript">
      ```typescript  
      // build.prod.ts
      import "dotenv/config";
      import { Template, defaultBuildLogger } from 'e2b';
      import { template } from './template';

      async function main() {
        await Template.build(template, 'custom-packages', {
          cpuCount: 2,
          memoryMB: 2048,
          onBuildLogs: defaultBuildLogger(),
        });
      }

      main().catch(console.error);
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      # build.prod.py
      from dotenv import load_dotenv
      from e2b import Template, default_build_logger
      from template import template

      load_dotenv()

      if __name__ == '__main__':
          Template.build(
              template,
              'custom-packages',
              cpu_count=2,
              memory_mb=2048,
              on_build_logs=default_build_logger(),
          )
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
</CodeGroup>

### 4. Build the template [#4-build-the-template]

Run the build script to create your custom template:

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    <CodeBlockTab value="JavaScript & TypeScript">
      ```bash  
      npx tsx build.prod.ts
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```bash  
      python build.prod.py
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
</CodeGroup>

This will build your template and you'll see build logs in the console.

### 5. Use your custom sandbox [#5-use-your-custom-sandbox]

Now you can create sandboxes from your custom template:

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    </CodeBlockTabsList>

    <CodeBlockTab value="JavaScript & TypeScript">
      ```js  
      import { Sandbox } from 'e2b'

      const sbx = await Sandbox.create("custom-packages")

      // Your packages are already installed and ready to use
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      from e2b import Sandbox

      sbx = Sandbox.create("custom-packages")

      # Your packages are already installed and ready to use
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
</CodeGroup>

***

## Install packages during the sandbox runtime [#install-packages-during-the-sandbox-runtime]

Use this option if don't know beforehand what packages you need in the sandbox. You can install packages with the package manager of your choice.

<Note>
  The packages installed during the runtime are available only in the running sandbox instance.
  When you start a new sandbox instance, the packages are not be available.
</Note>

### 1. Install Python packages with PIP [#1-install-python-packages-with-pip]

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    <CodeBlockTab value="JavaScript & TypeScript">
      ```js  
      import { Sandbox } from '@e2b/code-interpreter'

      const sbx = await Sandbox.create()
      sbx.commands.run('pip install cowsay') // This will install the cowsay package
      sbx.runCode(`
        import cowsay
        cowsay.cow("Hello, world!")
      `)
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      from e2b_code_interpreter import Sandbox

      sbx = Sandbox.create()
      sbx.commands.run("pip install cowsay") # This will install the cowsay package
      sbx.run_code("""
        import cowsay
        cowsay.cow("Hello, world!")
      """)
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
</CodeGroup>

### 2. Install Node.js packages with NPM [#2-install-nodejs-packages-with-npm]

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        Python
      </CodeBlockTabsTrigger>
    </CodeBlockTabsList>

    <CodeBlockTab value="JavaScript & TypeScript">
      ```js  
      import { Sandbox } from '@e2b/code-interpreter'

      const sbx = await Sandbox.create()
      sbx.commands.run('npm install cowsay') // This will install the cowsay package
      sbx.runCode(`
        const cowsay = require('cowsay')
        console.log(cowsay.say({ text: 'Hello, world!' }))
      `, { language: 'javascript' })
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      from e2b_code_interpreter import Sandbox

      sbx = Sandbox.create()
      sbx.commands.run("npm install cowsay") # This will install the cowsay package
      sbx.run_code("""
        import { say } from 'cowsay'
        console.log(say('Hello, world!'))
      """, language="javascript")
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
</CodeGroup>

### 3. Install packages with package manager of your choice [#3-install-packages-with-package-manager-of-your-choice]

Since E2B Sandboxes are Debian based machines, you can use any package manager supported by Debian.
You just need to make sure that the package manager is already installed in the sandbox.

For example, to install `curl` and `git`, you can use the following commands:

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    <CodeBlockTab value="JavaScript & TypeScript">
      ```js  
      import { Sandbox } from '@e2b/code-interpreter'

      const sbx = await Sandbox.create()
      await sbx.commands.run('apt-get update && apt-get install -y curl git')
      ```
    </CodeBlockTab>

    <CodeBlockTab value="Python">
      ```python  
      from e2b_code_interpreter import Sandbox

      sbx = Sandbox.create()
      sbx.commands.run("apt-get update && apt-get install -y curl git")
      ```
    </CodeBlockTab>
  </CodeBlockTabs>
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