> For the complete documentation index, see [llms.txt](https://docs.computesdk.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.computesdk.com/providers/sail.md).

# Sail

Sail provider for ComputeSDK - isolated Firecracker microVM sandboxes with fast startup, command execution, and native filesystem access.

[Sail](https://sailresearch.com) provides maximally-efficient Firecracker microVM sandboxes for running agent and developer workloads. They can live forever and bill only for active CPU, memory, and disk usage.

## Installation & Setup

```bash
npm install computesdk @computesdk/sail
```

Node.js 22 or newer is required. Create an API key at [app.sailresearch.com](https://app.sailresearch.com), then export it:

```bash
export SAIL_API_KEY=your_sail_api_key
```

## Usage

```typescript
import { sail } from '@computesdk/sail';

const compute = sail({ app: 'my-app' });

const sandbox = await compute.instances.create();
const result = await sandbox.runCommand('node --version');
console.log(result.stdout);

await sandbox.filesystem.writeFile('/tmp/result.txt', result.stdout);
console.log(await sandbox.filesystem.readFile('/tmp/result.txt'));

await sandbox.destroy();
```

## Configuration Options

```typescript
interface SailConfig {
  apiKey?: string;
  app?: string;
  image?: ImageSpec | Image;
}
```

`apiKey` falls back to `SAIL_API_KEY`. `app` falls back to `SAIL_APP`, then `computesdk`, and is created on first use when missing. `image` defaults to Sail's ARM64 Devbox builtin, which includes Node.js and Bun. Pass a different image when the workload needs another runtime or architecture.

Create accepts Sailbox `size` values `s`, `m`, and `l`, optional `memoryGib`, a name, and an `AbortSignal`. It defaults to `s`; explicit size choices override that default. Unsupported universal options are rejected rather than silently ignored.

## Supported Operations

| Method       | Supported | Notes                                                       |
| ------------ | --------- | ----------------------------------------------------------- |
| `create`     | Yes       | Defaults to an ARM64 Devbox on `S`.                         |
| `getById`    | Yes       | Returns `null` for missing or terminated Sailboxes.         |
| `list`       | Yes       | Lists live and actionable Sailboxes for the configured app. |
| `destroy`    | Yes       | Terminates the Sailbox.                                     |
| `runCommand` | Yes       | Supports cwd, environment, timeout, and background mode.    |
| `getInfo`    | Yes       | Maps current Sail lifecycle state to ComputeSDK.            |
| `getUrl`     | Yes       | Supports public HTTP/HTTPS and TCP listeners.               |
| `filesystem` | Yes       | Native read, write, mkdir, list, exists, and remove.        |
| Templates    | No        | Configure a Sail `Image` on the provider.                   |
| Snapshots    | No        | Use the native Sail SDK for checkpoints.                    |

`getUrl` preserves existing listener policy and rejects protocol conflicts instead of replacing a listener's allowlist.

Use `sandbox.getInstance()` for Sail-specific checkpoint, sleep, resume, SSH, listener allowlist, and credential-injection APIs.


---

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