---
title: Configuration
description: Configure Sandbox SDK deployments with Wrangler, Dockerfiles, environment variables, and transport modes.
image: https://developers.cloudflare.com/dev-products-preview.png
---

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

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# Configuration

Configure your Sandbox SDK deployment with Wrangler, customize container images, and manage environment variables.

[Wrangler configuration](https://developers.cloudflare.com/sandbox/configuration/wrangler/) 

Configure Durable Objects bindings, container images, and Worker settings in wrangler.jsonc.

[Dockerfile reference](https://developers.cloudflare.com/sandbox/configuration/dockerfile/) 

Customize the sandbox container image with your own packages, tools, and configurations.

[Environment variables](https://developers.cloudflare.com/sandbox/configuration/environment-variables/) 

Pass configuration and secrets to your sandboxes using environment variables.

[Transport modes](https://developers.cloudflare.com/sandbox/configuration/transport/) 

Configure HTTP or WebSocket transport to optimize communication and avoid subrequest limits.

[Sandbox options](https://developers.cloudflare.com/sandbox/configuration/sandbox-options/) 

Configure sandbox behavior with options like `keepAlive` for long-running processes.

## Related resources

* [Get Started guide](https://developers.cloudflare.com/sandbox/get-started/) \- Initial setup walkthrough
* [Wrangler documentation](https://developers.cloudflare.com/workers/wrangler/) \- Complete Wrangler reference
* [Docker documentation ↗](https://docs.docker.com/engine/reference/builder/) \- Dockerfile syntax
* [Security model](https://developers.cloudflare.com/sandbox/concepts/security/) \- Understanding environment isolation

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