# CodeSandbox — Instant Cloud Development Environments

> An online IDE and cloud dev environment platform that lets teams spin up full development setups in seconds directly from a repository.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

# CodeSandbox — Instant Cloud Development Environments

## Quick Use
```bash
# Open any GitHub repo in CodeSandbox by URL
# https://codesandbox.io/p/github/OWNER/REPO
# Or import a project via CLI
npx codesandbox-cli deploy ./my-project
# Local development with CodeSandbox SDK
npm install @codesandbox/sdk
```

## Introduction
CodeSandbox provides instant cloud development environments where every branch gets its own running dev server. Originally built as a browser-based React sandbox, it evolved into a full cloud IDE powered by Firecracker microVMs that can run any stack.

## What CodeSandbox Does
- Launches full cloud dev environments from any Git repository in seconds
- Provides a browser-based VS Code editor with terminal and preview panes
- Runs code in Firecracker microVMs with persistent filesystem and Docker support
- Generates shareable preview URLs for every branch automatically
- Offers an SDK for programmatic sandbox creation and management

## Architecture Overview
CodeSandbox runs each environment inside a Firecracker microVM with memory snapshotting for near-instant resume. The browser client connects to the VM via WebSocket for terminal, LSP, and file operations. A proxy layer routes HTTP traffic to generate unique preview URLs per branch.

## Self-Hosting & Configuration
- Sign up at codesandbox.io and connect your GitHub or GitLab account
- Add a `.codesandbox/tasks.json` to define setup and run commands
- Configure environment resources (CPU, RAM) in project settings
- Use the Pitcher runtime for custom Docker-based environments
- Integrate with your CI/CD pipeline via the CodeSandbox API or SDK

## Key Features
- Sub-second environment resume via memory snapshots
- Built-in VS Code editor with full extension support
- Docker and docker-compose support inside cloud environments
- Unique preview URLs for each branch with live collaboration
- Programmatic SDK for embedding sandboxes in documentation or tools

## Comparison with Similar Tools
- **StackBlitz** — WebContainer-based; runs Node.js in the browser, limited backend support
- **Gitpod** — Similar cloud IDE; uses custom workspace images instead of microVMs
- **GitHub Codespaces** — Microsoft-backed; deeper GitHub integration, higher cost
- **Coder** — Self-hosted remote dev environments; requires your own infrastructure
- **Replit** — Consumer-focused online IDE; less suited for professional workflows

## FAQ
**Q: Is CodeSandbox free?**
A: A free tier is available with limited VM hours. Paid plans offer more compute, memory, and collaboration features.

**Q: Can I run Docker inside CodeSandbox?**
A: Yes. Cloud environments support Docker and docker-compose for running databases, services, and custom toolchains.

**Q: Does CodeSandbox work offline?**
A: No. Environments run in the cloud and require an internet connection. Your code is persisted on the server.

**Q: Can I use my own VS Code extensions?**
A: Yes. The editor supports installing VS Code extensions from the Open VSX registry.

## Sources
- https://github.com/codesandbox/codesandbox-client
- https://codesandbox.io/docs

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Source: https://tokrepo.com/en/workflows/codesandbox-instant-cloud-development-environments-65fc6397
Author: Script Depot