---
title: Lightcone OS | Lightcone
description: The desktop runtime that Northstar operates in. Optimized for AI-driven computer use.
---

When Northstar operates a computer, it runs inside **Lightcone OS** — a minimal Linux desktop runtime tuned for AI operation. Consistent rendering, fast boot, pre-installed tools, and a display pipeline optimized for Northstar’s vision model.

You don’t need to think about Lightcone OS to use Northstar — it’s the default environment for every computer. This page covers what’s inside it for cases where you need to install software, customize the environment, or understand what Northstar is looking at.

## What’s included

Every Lightcone OS instance comes with:

- **Web browser** — Chromium with stealth mode and anti-detection
- **Terminal** — full shell with `bash`, `python3`, `node`, `curl`, `git`, and standard Unix tools
- **Package manager** — `apt-get` for installing additional software
- **File system** — isolated per computer, writable, with standard Linux paths
- **Display server** — X11 with consistent viewport configuration
- **Network stack** — full internet access, optional residential proxy routing

## Why a custom runtime

Computer-use models work by looking at screenshots. The quality of Northstar’s decisions depends on the visual environment being legible and predictable. Stock Linux desktops introduce variability — different themes, fonts, icon sets, display scaling — that degrades model performance.

Lightcone OS removes that variability: deterministic fonts, DPI, and color profiles across every instance. Northstar produces more reliable actions when the environment is consistent.

## Installing software

Since it’s a full Linux environment, install anything:

```
with client.computer.create(kind="desktop") as computer:
    client.computers.exec.sync(computer.id, command="apt-get install -y libreoffice")
    client.computers.exec.sync(computer.id, command="libreoffice --calc &")
    computer.wait(3)
    result = computer.screenshot()
```

```
await client.computers.exec.sync(computer.id!, {
  command: "apt-get install -y libreoffice",
});
await client.computers.exec.sync(computer.id!, {
  command: "libreoffice --calc &",
});
```

Use [persistent state](/guides/computers#persistent-state/index.md) to save installed software across sessions so you don’t reinstall every time.

## Display configuration

Configure the viewport when creating a computer:

```
with client.computer.create(
    kind="desktop",
    display={"width": 1920, "height": 1080, "scale": 1.0},
) as computer:
    pass
```

```
const computer = await client.computers.create({
  kind: "desktop",
  display: { width: 1920, height: 1080, scale: 1.0 },
});
```

The default is 1280x720, which works well for most tasks and keeps screenshot sizes manageable for Northstar’s inference.

## See also

- [**Computers**](/guides/computers/index.md) — create, interact with, and manage environments
- [**Shell commands**](/guides/shell-commands/index.md) — run terminal commands
- [**How Lightcone works**](/guides/how-lightcone-works/index.md) — architecture overview