# Sandbox Next

Build or maintain Cloudflare Sandbox apps on @cloudflare/sandbox@next (SDK 1.0 preview).

- Repository: https://github.com/cloudflare/skills (3246 stars)
- Category: DevOps
- License: Apache-2.0
- Last updated: 2026-10-31
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add cloudflare/skills --skill sandbox-next -g -a claude-code -y`
Codex: `npx skills add cloudflare/skills --skill sandbox-next -g -a codex -y`
Cursor: `npx skills add cloudflare/skills --skill sandbox-next -g -a cursor -y`
Gemini CLI: `npx skills add cloudflare/skills --skill sandbox-next -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add cloudflare/skills`

## Description

Build or maintain Cloudflare Sandbox apps on @cloudflare/sandbox@next (SDK 1.0 preview). Use sandbox-migrate-to-next when porting a stable app.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Sandbox SDK, `@next` (1.0 preview)

Isolated Linux environments on [Cloudflare Containers](https://developers.cloudflare.com/containers/index.md), driven from Workers.

**Prefer preview docs and installed `@next` types over memory.** APIs change; this skill is a gate, a contract, and a retrieval map, not a full manual.

We recommend **new projects** on this line. Apps still on the default package use **`sandbox-stable`**. Port only when asked, via **`sandbox-migrate-to-next`**.

## 1. Gate, confirm the package line

Before writing code, inspect the app:

| Check | Must match |
| ----- | ---------- |
| npm dependency | `@cloudflare/sandbox@next` (or another preview tag) |
| Container image | Same line (e.g. `cloudflare/sandbox:next`, `next-python`) |

| If you find… | Action |
| ------------ | ------ |
| Default `@cloudflare/sandbox` (no `@next`) | **Stop.** Load **`sandbox-stable`**. Do not apply this skill’s APIs. |
| User wants to port stable → `@next` | **Stop.** Load **`sandbox-migrate-to-next`**. |
| Self-deployed **bridge** only | Bridge is **not** on the 1.0 preview line yet. Keep bridge on stable package + image. [Bridge (stable)](https://developers.cloudflare.com/sandbox/sdk/bridge/index.md) |

Never mix an `@next` Worker package with a stable container image (or the reverse).

Skills install: [Agent setup](https://developers.cloudflare.com/agent-setup/index.md) · [cloudflare/skills](https://github.com/cloudflare/skills)

## 2. Contract, non-negotiables

The rest: https://github.com/cloudflare/skills/blob/HEAD/skills/sandbox-next/SKILL.md