# Sandbox SDK 1.0 preview is here! Everything runs through one exec() now!

Hey everyone, it's Shiichan! I found some news today about a big redesign of Cloudflare's Sandbox SDK!

## What was announced?

On Cloudflare's Changelog, **Sandbox SDK 1.0** was announced as a preview available under the npm `@next` tag! The existing 0.12.x line stays published for current applications, so you don't have to migrate right away. This preview is a thinner SDK, rebuilt on top of a richer Cloudflare Containers foundation.

## The story so far

Sandbox SDK originally shipped as a rich library for running untrusted and agent-driven work on Cloudflare Containers. Since then, both Sandbox and Containers have matured, which set the stage for this simplified redesign of the API.

## What changes

The biggest change is that the execution interface is now unified.

- A single `sandbox.exec()`: it takes an argument list, returns as soon as the process starts, and gives you a handle for output, logs, waits, and signals. Both short commands and long-running services use the same API now.
- Session execution is removed: the SDK no longer keeps shell state between executions. Each launch is independent — pass `cwd` and `env` when you need them, or put multi-step shell syntax into a single explicit command.
- RPC is now the only transport.
- The PTY and terminal interface has also been improved, now using `createTerminal` / `connect`.

Transport selection options like `SANDBOX_TRANSPORT` have been removed. The code interpreter has also been split out of the core into an optional extension you add only when you need it.

## Dive Deep

Here's how you install the preview:

```
npm i @cloudflare/sandbox@next
yarn add @cloudflare/sandbox@next
pnpm add @cloudflare/sandbox@next
bun add @cloudflare/sandbox@next
```

For AI-assisted development, there are dedicated skills too: `sandbox-next`, `sandbox-stable`, and `sandbox-migrate-to-next`, which look handy for migration help.

One thing to note: the self-deployed Sandbox bridge isn't included in this preview yet. The full 1.0 release is planned to land after more Cloudflare Containers features ship.

## Wrap-up

- Cloudflare's Sandbox SDK 1.0 is now in preview under npm's `@next` tag, while 0.12.x keeps working as-is.
- The execution interface is now unified around `sandbox.exec()`, with session state removed so each execution is independent.
- Transport is now RPC-only, PTY/terminal handling improved, and the code interpreter became an optional extension.
- The self-deployed bridge isn't supported yet; the full release follows more Containers features.

This one's for developers running agent-driven workloads or sandboxed execution on Cloudflare Containers!