just-bash.md

description	just-bash provider for ComputeSDK — local sandboxed bash execution with a virtual filesystem. No external services, containers, or authentication required.
layout	width title description tableOfContents outline pagination metadata tags actions default visible true visible visible true visible true visible true visible true visible true visible true

Just Bash

just-bash provider for ComputeSDK — local sandboxed bash execution with a virtual filesystem. No external services, containers, or authentication required.

Installation & Setup

npm install @computesdk/just-bash

No environment variables or credentials are required. just-bash runs entirely locally, interpreting commands in TypeScript against an in-memory virtual filesystem.

Usage

import { justBash } from '@computesdk/just-bash';

const compute = justBash({});

// Create sandbox
const sandbox = await compute.sandbox.create();

// Run a command
const result = await sandbox.runCommand('echo "Hello from just-bash!"');
console.log(result.stdout); // "Hello from just-bash!"

// Clean up
await sandbox.destroy();

Configuration Options

interface JustBashConfig {
  /** Enable Python support via pyodide (disabled by default) */
  python?: boolean;
  /** Initial files to populate in the virtual filesystem */
  files?: BashOptions['files'];
  /** Initial environment variables */
  env?: Record<string, string>;
  /** Working directory (defaults to /home/user) */
  cwd?: string;
  /** Custom filesystem implementation (InMemoryFs by default; also OverlayFs, ReadWriteFs, MountableFs) */
  fs?: BashOptions['fs'];
  /** Custom commands created with defineCommand() */
  customCommands?: BashOptions['customCommands'];
  /** Network configuration for curl (disabled by default) */
  network?: BashOptions['network'];
}

Supported Operations

Method	Supported	Notes
create	✅	Creates an in-process sandbox; runtime: 'python' also enables Python.
getById	✅	Looks up sandboxes tracked in the current process.
list	✅
destroy	✅	Removes the sandbox from the in-process registry.
runCommand	✅	Supports env and cwd. 60+ built-in commands (jq, awk, sed, grep, etc.).
getInfo	✅
getUrl	❌	Throws — just-bash is a local sandbox with no network capabilities.
filesystem	✅	readFile, writeFile, mkdir, readdir, exists, remove.

Notes

• Local, no network — no API keys, containers, or external services. Ideal for tests, CI, AI-agent tooling, and offline use.
• In-memory by default — files do not persist across process restarts unless you supply an OverlayFs, ReadWriteFs, or MountableFs backend via fs.
• Not real processes — commands are interpreted in TypeScript, not executed as OS processes; there is no real Node.js runtime.
• Python via pyodide — requires python: true and runs a WebAssembly-based interpreter.