---
title: just-bash Sandbox
description: Use a pure-JavaScript shell and virtual filesystem.
---

# just-bash Sandbox



`JustBashSandbox.environment()` provides a shell and filesystem without starting a container or VM.

```ts
import { defineSandbox } from "eve/sandbox";
import { JustBashSandbox } from "eve/sandbox/just-bash";

export const environment = JustBashSandbox.environment();
export default defineSandbox(() => environment.open());
```

just-bash can prepare and persist its virtual filesystem. It cannot use OCI images or Dockerfiles, does not run native processes, and provides no network isolation. The session does not expose `setNetworkPolicy()`.

See the [sandbox overview](/docs/sandbox) for managed workspace, skills, parent inheritance, and custom providers.


---

For a semantic overview of all documentation, see [/sitemap.md](/sitemap.md)

For an index of all available documentation, see [/llms.txt](/llms.txt)

For agent-facing discovery, including API and MCP surfaces, see [/agents.md](/agents.md)