Source: https://harnsy.dev/docs/install

> harnsy installs with one command on Linux, macOS and Windows. It starts as a background service on your computer. For running it needs no server of ours; what it contacts, and when, is in the FAQ “Where does my data go?”.

# Install

harnsy installs with one command on Linux, macOS and Windows. It starts as a background service on your computer. For running it needs no server of ours; what it contacts, and when, is in the FAQ “Where does my data go?”.

The full page is [Install](https://harnsy.dev/install); this page is the short version.

**Before you start.** Have at least one AI program installed: Claude Code, Codex or OpenCode. You sign in to Claude Code or Codex in the first run (page 2); an OpenCode agent works when harnsy starts it. For terminals, harnsy uses tmux, or its own built-in terminal (nothing to install; Windows 10 1809 or newer). The installer offers one. Without either, messages, teams and the dashboard still work, and harnsy opens no agents by itself.

### Steps

**1. See the plan first, without changing anything.**

**Linux and macOS**

```bash
curl -fsSL https://harnsy.dev/install.sh | sh -s -- --dry-run
```

**Windows**

```powershell
$env:HARNSY_INSTALL_ARGS = "--dry-run"; irm https://harnsy.dev/install.ps1 | iex
```

**You see:** every step and every diff the installer would make. Nothing is written.

**2. Install.** Run the same command without `--dry-run`.

**Linux and macOS**

```bash
curl -fsSL https://harnsy.dev/install.sh | sh
```

**Windows**

```powershell
irm https://harnsy.dev/install.ps1 | iex
```

harnsy goes to `~/.local/bin` (Windows: `%LOCALAPPDATA%\harnsy\bin`) and starts as a user service. The download is checked against the release’s `SHA256SUMS`.

**3. Answer the installer’s questions in a terminal.** It asks before every change to your own files: the terminal choice, the tray (and whether it starts at login), the briefing hook and the answer hook for Claude Code and Codex, the “allow harnsy” entries for Claude Code’s auto mode, and the Claude status line. Each change is shown as a diff, and your yes is kept for the next install.

> Tip
> 
> On a computer that never had harnsy, `--first-run` says yes to the main questions and then prints “What changed on this computer” and how to undo it.

**Linux and macOS**

```bash
curl -fsSL https://harnsy.dev/install.sh | sh -s -- --first-run
```

**Windows**

```powershell
$env:HARNSY_INSTALL_ARGS = "--first-run"; irm https://harnsy.dev/install.ps1 | iex
```

**4. Check that it runs.**

Shell

```bash
curl -s http://127.0.0.1:7788/healthz
```

**You see:** `ok`. Then open `http://127.0.0.1:7788` in your browser.

### Upgrade

harnsy never checks for updates by itself. Check, then update:

Shell

```bash
harnsy update --check
harnsy update
```

The dashboard has the same as “Check for updates” and “Update” buttons. Running the install command again also works. Your data in `~/.harnsy` stays. The node restarts for a few seconds, and agent sessions keep running.

> Note
> 
> A message sent in those few seconds fails: send it again. On Windows the installer asks before it restarts the node.

### Going back

After an update:

Shell

```bash
harnsy update --rollback --yes
```

Or install an older release over a newer one (the variable goes to `sh`, not to `curl`):

Shell

```bash
curl -fsSL https://harnsy.dev/install.sh | HARNSY_VERSION=<tag> sh -s -- --allow-older
```

### Undo

Shell

```bash
harnsy uninstall --dry-run
harnsy uninstall
```

It removes the service, the tray, the program, and only the settings entries the install itself added (the briefing and answer hooks, the auto-mode entries, the status line; yours is put back if the install wrapped it), after showing a diff and asking.

> Note
> 
> Earlier backups are not put back. It keeps your data in `~/.harnsy`, your backups and a terminal choice you made yourself. It does not undo permission rules or folder trust you gave Claude Code. Without a terminal it asks nothing and leaves the settings entries.

Since harnsy 0.1.

Anthropic, Claude Code, OpenAI, ChatGPT, Codex, OpenCode, Telegram, Discord, GitHub, Apple, macOS, iOS, iPhone, Safari, Google, Android, Chrome, Microsoft, Windows, Windows Security, Defender and QR Code are names of their owners’ products. harnsy is not affiliated with or endorsed by them. iOS is a trademark of Cisco used under licence by Apple; QR Code is a registered trademark of DENSO WAVE INCORPORATED. No logos.