Browser vs Node

The same @lifo-sh/core runs in a browser tab and in Node. The kernel, shell, commands, and Node layer are environment-agnostic — only the bottom "host bridge" differs.

What's identical#

• The Sandbox API, shell, commands, and the Node runtime behave the same.
• os.platform() returns "lifo" in both, so code can detect the VM and branch on it (a sanctioned pattern for template code that must work with or without Lifo).

What differs#

Mounting the host filesystem (Node)#

In Node, the mounts option backs a subtree of the VFS with a real directory, so a box reads and writes files on your machine:

const sandbox = await Sandbox.create({
  mounts: [
    { virtualPath: "/workspace", hostPath: "/Users/me/project" },
    { virtualPath: "/readonly", hostPath: "/etc", readOnly: true },
  ],
});

This uses NativeFsProvider under the hood; you can supply a custom NativeFsModule if you're not on node:fs.

Headless runs (Node)#

Without a terminal, a box runs headless — ideal for scripting and tests. There's no TTY (so interactive prompts don't fire unless you feed stdin) and no CORS restriction (outbound fetch works directly). This is the fastest way to drive the VM in a test:

const sandbox = await Sandbox.create(); // no terminal
const { stdout, exitCode } = await sandbox.commands.run("node build.js");

On the roadmap#

Choosing the filesystem backend explicitly (IndexedDB/OPFS in the browser, the host FS via the CLI, or purely volatile) and a standalone lifo binary that runs isolated boxes on a host are on the roadmap.