Arch Linux and CachyOS Install Guide

Arch Linux is one of the two recommended Polaris package paths, and the official Polaris-arch-x86_64.pkg.tar.zst asset ships with every release. CachyOS and most pacman-compatible Arch derivatives should start with this same package.

SteamOS is pacman-based but is not covered by this page: it has its own versioned package and a read-only root, so follow the SteamOS guide instead. The two packages are not interchangeable.

Install

wget --output-document=./Polaris-arch-x86_64.pkg.tar.zst https://github.com/papi-ux/polaris/releases/latest/download/Polaris-arch-x86_64.pkg.tar.zst &&
sudo pacman -U ./Polaris-arch-x86_64.pkg.tar.zst &&
sudo -H polaris --setup-host &&
polaris

The package installs the host binary, the web console assets, desktop metadata, and the user service file. Host integration stays explicit: --setup-host is a separate step you run yourself.

Open https://localhost:47990/#/welcome, create your web UI account, and pair a client.

What --setup-host does

It installs the udev rules and modules-load configuration that make virtual input work, and reports anything it could not complete.

[!WARNING] Only add --enable-kms when you actually need DRM/KMS capture: sudo -H polaris --setup-host --enable-kms grants cap_sys_admin. Polaris works without it on the default compositor and Headless Stream paths.

If you ran --setup-host on a version before v1.3.5, a copy of the udev rules may still sit in /etc/udev/rules.d/60-polaris.rules and override the packaged file. Host setup keeps it and warns rather than deleting it; see Troubleshooting for the check and removal.

Autostart

systemctl --user enable --now polaris

Arch derivatives

CachyOS is expected to work through this package path. If a derivative renames dependencies or ships different runtime helpers, the package may refuse to install or Polaris may fail to find a helper at launch. In that case use the local package or source build in Building Polaris, and please report the derivative-specific gap with your distro, GPU, driver, compositor, and package details.

Verify the stream path

Confirm the recommended Linux configuration:

headless_mode = enabled
linux_use_cage_compositor = enabled
linux_prefer_gpu_native_capture = enabled

What you’ll see: with this configuration the built-in Desktop entry streams Polaris’ private compositor — an intentionally empty screen (right-click opens the session menu) until a game is launched from your client. If you wanted a desktop stream instead, pick the mode for it:

I want	Set linux_stream_mode to
My real desktop, at host resolution	desktop_display (Mirror Desktop)
An extra display, sized to the client	host_virtual_display
An isolated game-only session, desktop untouched	headless_stream (this recommended setup)

Moonlight-protocol clients can also request the mirror per launch with mirrorDesktop=1 on /launch. And mind the trap: headless_mode = enabled without linux_use_cage_compositor selects host_virtual_display, not a headless session.

Then start a game and read the active runtime, capture path, and encoder in Mission Control. See Runtime and Streaming Model for what those values mean.

Upgrade

wget --output-document=./Polaris-arch-x86_64.pkg.tar.zst https://github.com/papi-ux/polaris/releases/latest/download/Polaris-arch-x86_64.pkg.tar.zst &&
sudo pacman -U ./Polaris-arch-x86_64.pkg.tar.zst &&
sudo -H polaris --setup-host &&
systemctl --user restart polaris

Your configuration, pairing keys, and library stay in ~/.config/polaris across upgrades.

Uninstall

systemctl --user disable --now polaris
sudo pacman -R polaris

Package-owned udev rules and modules-load configuration are removed with the package. Host configuration in ~/.config/polaris is left in place.

Debug package

Arch and SteamOS also publish a polaris-debug package. Install it when you need coredumpctl info polaris to produce a real backtrace for a crash report.