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.