# Base image

Every sandbox starts from one image: Ubuntu 24.04 LTS, on HareBox's own Linux 6.18 LTS kernel. It has real systemd, a `user` account with passwordless `sudo`, Docker with BuildKit and Compose, and nested `/dev/kvm`. Ubuntu 26.04 LTS is planned; the API accepts only `ubuntu-24.04` until its image exists.

> **Status:** the image is built and checked on real VMs on the development machine (`tests/spikes/run.py`). No rented server has run it yet.

## What's installed

Every version is pinned, and every download is checked against its SHA-256 before it goes into the image. This table is generated from the image recipe in `host/ch/image/`.

<!-- toolchain -->

Also in the image:

- `corepack` shims for `pnpm` and `yarn`, which fetch on first use.
- The Android SDK command-line tools in `/opt/android-sdk`.
- `harebox-harness`, `harebox-android-setup` and `harebox-computer` (the desktop and its MCP server) in `/usr/local/bin`.
- A desktop (Xvfb, Xfce, x11vnc and noVNC) that starts on first use. See [Desktop](../guides/desktop.html).
- 64-bit Wine. 32-bit Windows programs need Wine's 32-bit libraries, which aren't included.

## Installed on first use

These have no artifact that can be pinned for offline install, so they install from their publisher when you first ask. That needs the sandbox's network.

```sh
harebox-harness list
harebox-harness install kimi        # also: vibe, hermes, prime, cursor
harebox-android-setup 35            # emulator, platform tools and an API 35 system image
```

## What a stop keeps

A stop saves the whole disk, so `~/.cache`, `/tmp` and Docker's build cache come back on resume, so a resumed sandbox picks up warm caches instead of rebuilding them. Sleep keeps memory and running programs as well.