> For the complete documentation index, see [llms.txt](https://docs.monarchlinux.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.monarchlinux.com/getting-started/installation.md).

# Installation

Download Monarch, create installation media, and complete the current installer flow.

Monarch is currently distributed as a beta ISO.

{% hint style="info" %}
[Download the latest Monarch beta ISO](https://iso.monarchlinux.com/monarch-nightly.iso). The downloaded file is named `monarch-nightly.iso`.
{% endhint %}

## Verify the download

Before writing the USB drive, download the [GPG signature](https://iso.monarchlinux.com/monarch-nightly.iso.sig) and [SHA-256 checksum](https://iso.monarchlinux.com/monarch-nightly.iso.sha256) into the same directory as `monarch-nightly.iso`. The nightly URL is replaced on each successful release: download all three files together.

### Check the SHA-256 checksum

On Linux:

```
sha256sum -c monarch-nightly.iso.sha256
```

On macOS:

```
shasum -a 256 -c monarch-nightly.iso.sha256
```

On Windows PowerShell, run `Get-FileHash .\monarch-nightly.iso -Algorithm SHA256` and compare the result with the value in the downloaded `.sha256` file.

The checksum detects a corrupted or mismatched download. It does not authenticate the publisher; use the GPG signature as well.

### Verify the GPG signature

Install GnuPG for your operating system. Download the [Monarch public signing key](https://raw.githubusercontent.com/monarch-os/monarch-pkgs/main/pkgbuilds/monarch-keyring/monarch.gpg) as `monarch.gpg`, then inspect it before importing:

```
gpg --show-keys --with-fingerprint monarch.gpg
```

Compare the complete primary-key fingerprint with:

```
519B C3D5 AEA6 52C9 4F89 F0AA C13B 3766 D969 CE82
```

Only if it matches, import the key and verify the ISO:

```
gpg --import monarch.gpg
gpg --verify monarch-nightly.iso.sig monarch-nightly.iso
```

Require a good signature from that exact key. GnuPG may warn that you have not certified the owner's identity; do not mark the key as trusted merely to silence the warning. Comparing the fingerprint is essential.

{% hint style="danger" %}
Do not install an image with a failed checksum, a bad signature or a different signing fingerprint. If a nightly publication happened during your downloads, download the ISO and both sidecars again and repeat the checks. If verification still fails, stop and report it rather than bypassing verification.
{% endhint %}

## Create a bootable USB drive

### Linux

Insert the USB drive and identify the whole device:

```bash
lsblk
```

Write the ISO to that device:

```bash
sudo dd if=monarch-nightly.iso of=/dev/<device> bs=4M status=progress oflag=sync
```

{% hint style="danger" %}
Replace `/dev/<device>` with the USB drive itself, such as `/dev/sdb`, not a partition such as `/dev/sdb1`. This erases every file on the selected device.
{% endhint %}

### Windows

Use [Rufus](https://rufus.ie/) or [balenaEtcher](https://etcher.balena.io/):

1. Select `monarch-nightly.iso`.
2. Select the USB drive.
3. Start the write and wait for it to finish.

### macOS

Use [balenaEtcher](https://etcher.balena.io/) and select the ISO and USB drive. You can also use `dd` from Terminal if you are comfortable identifying the correct disk.

## Boot the installer

1. Restart the computer with the USB drive connected.
2. Open the firmware boot menu. Common keys are `F12`, `Esc`, `F9`, and `Delete`.
3. Select the Monarch USB drive.

The ISO supports both UEFI and legacy BIOS systems. Boot in UEFI mode if you want to install Monarch into free space beside an existing operating system.

## Configure the installation

The installer collects these choices before it changes the disk:

1. Keyboard layout.
2. Username and password.
3. Full name and email address for the Git identity.
4. Hostname and timezone.
5. Software profile.
6. Target disk and installation layout.
7. Disk encryption.

The **full** software profile includes Monarch's optional applications, web apps, terminal integrations, and security tools. The **reduced** profile keeps the Monarch desktop while omitting those optional packages.

### Installation layout

A **full-disk installation** erases the selected disk.

On UEFI systems, the installer can also use a contiguous area of at least 32 GiB of unallocated space. Existing partitions are preserved. If the disk contains Windows with BitLocker, BitLocker must be completely disabled and the volume fully decrypted first; suspending protection is not sufficient.

{% hint style="warning" %}
Check the selected disk carefully. Do not select the USB drive containing the installer.
{% endhint %}

### Encryption

Full-disk and free-space installations start with encryption enabled. The final disk confirmation screen shows the effective choice. Press `Ctrl+C` on that screen to switch between encrypted and unencrypted installation, then confirm to continue.

On the first keyboard screen, `Ctrl+C` instead offers **Prepare for another owner**. This installs the system without creating its final user; the owner completes setup on first boot.

## Finish the installation

The installation dashboard reports progress and validates the installed boot configuration before declaring success. If installation fails, it can show the complete log and offer recovery actions.

When the installer finishes, reboot, remove the USB drive, and start Monarch from the installed disk.