import Image from 'next/image'

# Creating Custom Sandbox

In this guide, we'll create a custom E2B sandbox with preinstalled dependencies and files.
Once the sandbox is built, we'll show how to spawn and control it with our SDK.

## Prerequisites
1. [Node.js](https://nodejs.org/) 18.0.0 or later
1. [E2B CLI](/cli/installation)

## 1. Install E2B CLI

<CodeGroup isTerminalCommand title="Install CLI" isRunnable={false}>
```bash
npm install -g @e2b/cli@latest
```
</CodeGroup>

<Note>
You need Node.js 18.0.0 or later to install the CLI.
</Note>

## 2. Login to CLI
Before you create your first custom sandbox, you will need to authenticate in the CLI with your E2B account.
Run the following command in your terminal.
<CodeGroup isTerminalCommand title="Login to CLI" isRunnable={false}>
```bash
e2b login
```
</CodeGroup>

<Note>
You need to have an existing E2B account to login. Sign up [here](/getting-started/api-key).
</Note>

## 3. Create `e2b.Dockerfile`
To describe how your custom sandbox will look like, create a new Dockerfile and name it `e2b.Dockerfile`.
We use this Dockerfile as the [template file](/sandbox/templates/template-file).

<Note>
Run `e2b init` to create `e2b.Dockerfile` in the current directory.
</Note>

We want our custom sandbox to have the [ffmpeg](https://www.ffmpeg.org/) isntalled - ffmpeg is a tool for editing video and audio files.

<CodeGroup isFileName title="e2b.Dockerfile" isRunnable={false}>
```bash
# You can use most of the Debian-based base images
FROM ubuntu:22.04

# Install the ffmpeg tool/
RUN apt update \
    && apt install -y ffmpeg
```
</CodeGroup>

## 4. Build custom sandbox
Now it's time to create your custom sandbox based on the sandbox template file (the `e2b.Dockefile` file) you just created in the previous step.

Run the following command inside the template file directory in your terminal.
<CodeGroup isTerminalCommand title="Build sandbox template" isRunnable={false}>
```bash
e2b build --name "my-agent-sandbox"
```
</CodeGroup>

<Note>
Use the `.dockerignore` file to exclude files from the sandbox template.
</Note>

The final output should look similar to this.

<CodeGroup title="Build output" isRunnable={false}>
```bash
Preparing sandbox template building (1 files in Docker build context).
Found ./e2b.Dockerfile that will be used to build the sandbox template.
Started building the sandbox template my-agent-sandbox

# Truncated for visibility
# ...
# ...

Running postprocessing. It can take up to few minutes.

Postprocessing finished.

✅ Building sandbox template my-agent-sandbox finished.

┌ Usage examples ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│                                                                                                                                                      │
│  You can use E2B Python or JS SDK to spawn sandboxes now.                                                                                            │
│  Find more here - https://e2b.dev/docs/guide/custom-sandbox in Spawn and control your sandbox section.                                               │
│                                                                                                                                                      │
│───────────────────────────────────────────────────────────────────── Python SDK ─────────────────────────────────────────────────────────────────────│
│                                                                                                                                                      │
│  from e2b import Sandbox                                                                                                                             │
│                                                                                                                                                      │
│  # Start sandbox                                                                                                                                     │
│  sandbox = Sandbox("my-agent-sandbox")                                                                                                               │
│                                                                                                                                                      │
│  # Interact with sandbox. Learn more here:                                                                                                           │
│  # https://e2b.dev/docs/sandbox/overview                                                                                                             │
│                                                                                                                                                      │
│  # Close sandbox once done                                                                                                                           │
│  sandbox.close()                                                                                                                                     │
│                                                                                                                                                      │
│─────────────────────────────────────────────────────────────────────── JS SDK ───────────────────────────────────────────────────────────────────────│
│                                                                                                                                                      │
│  import { Sandbox } from '@e2b/sdk'                                                                                                                  │
│                                                                                                                                                      │
│  // Start sandbox                                                                                                                                    │
│  const sandbox = await Sandbox.create('my-agent-sandbox')                                                                                            │
│                                                                                                                                                      │
│  // Interact with sandbox. Learn more here:                                                                                                          │
│  // https://e2b.dev/docs/sandbox/overview                                                                                                            │
│                                                                                                                                                      │
│  // Close sandbox once done                                                                                                                          │
│  await sandbox.close()                                                                                                                               │
│                                                                                                                                                      │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Execution time: 42.55s
```
</CodeGroup>


This will create the `e2b.toml` file storing the sandbox config.
<CodeGroup isFileName title="e2b.toml" isRunnable={false}>
```toml
# This is a config for E2B sandbox template
template_id = "1wdqsf9le9gk21ztb4mo"
dockerfile = "e2b.Dockerfile"
template_name = "my-agent-sandbox"
```
</CodeGroup>

| Sandbox template name | Sandbox template ID |
---|---|
|`my-agent-sandbox`|`1wdqsf9le9gk21ztb4mo`|

### Updating your sandbox template
If you want to update your sandbox template, you run the same command you did to build it.
This will rebuild the template.

<CodeGroup isTerminalCommand title="Update sandbox template" isRunnable={false}>
```bash
e2b build
```
</CodeGroup>

## 5. Spawn and control your sandbox

Now you can use the [E2B SDK](/getting-started/installation) to spawn & control your new custom sandbox.

The sandbox template name is `my-agent-sandbox`. We'll use it as an unique identifier and pass it to the SDK as the `template` parameter.
This way, we'll be able to spawn our custom sandbox and control it with the SDK.

<CodeGroup title="Spawn & control your custom sandbox" isRunnable={true}>
```js {{ language: 'js' }}
import { Sandbox } from '@e2b/sdk'

// Spawn your custom sandbox
const sandbox = await Sandbox.create({ template: 'my-agent-sandbox' }) // $HighlightLine

// Interact with sandbox. Learn more here:
// https://e2b.dev/docs/sandbox/overview

// Close sandbox once done
await sandbox.close()
```

```python {{ language: 'python' }}
from e2b import Sandbox

# Spawn your custom sandbox
sandbox = Sandbox(template="my-agent-sandbox") # $HighlightLine

# Interact with sandbox. Learn more here:
# https://e2b.dev/docs/sandbox/overview

# Close sandbox once done
sandbox.close()
```
</CodeGroup>