# Steamify CachyOS Turn a CachyOS desktop PC into a SteamOS-style console: it boots straight into Steam's Big Picture (gamescope), and you can switch to the KDE Plasma desktop and back whenever you like - just like on a Steam Deck or Valve's Steam Machine. ## What you get The wizard is a menu: pick what you want, and it turns each part on or off. Everything you turn off is put back the way it was. 1. **SteamOS conversion** - boots straight into gaming mode, **Switch to Desktop** in Steam works and so does going back (the **Return to Gaming Mode** icon on the desktop), you're back in gaming mode after a restart, and Steam's on-screen keyboard (Steam + X) also works on the desktop. 2. **Boot into: [gamescope] / desktop** - a sub-option of 1, shown under it while it's ticked: where the PC starts. Gamescope (gaming mode) is the default; choose desktop to start in KDE Plasma instead, with Return to Gaming Mode one double-click away. 3. **SteamOS theme** - the Vapor look for the desktop (CachyOS's `cachyos-vapor` package). 4. **Steam Deck/Machine icons** - Steam Deck button icons in gaming mode. 5. **Single user mode** - like SteamOS: never a login or lock screen, no user switching or logging out. Typing a password with a controller is no fun. (Needs 1.) 6. **Steamify shortcut** - a "Steamify CachyOS" icon on the desktop and in the app launcher (the Steam logo with a gear) that opens the newest version of Steamify in Konsole, so you don't need the install command again. 7. **Steam Machine support** - only shown on a Valve Steam Machine: the driver for the front LED bar, and the hardware settings in Steam (fan, TV control over HDMI-CEC). 8. **Update BIOS** - only on a Steam Machine, opt-in and at your own risk: installs the newest Steam Machine BIOS from Valve (see [BIOS updates](#bios-updates-steam-machine)). ## Requirements - CachyOS with the KDE Plasma desktop (the default CachyOS Desktop edition) - Your normal user account, with permission to use `sudo` ## Installation Open **Konsole** on your Plasma desktop and run: ```bash curl -fsSL https://github.com/theupriser/steamify-cachyos/releases/latest/download/steamify.sh | bash ``` (Before 0.9.0 the script was called `setup-gamescope-boot.sh`; that name still works in the download URL.) That downloads and runs the latest single-file version, and works in any shell, including fish (CachyOS's default). Prefer to keep a copy, or to look at the script first? Clone the repository instead: ```bash git clone https://github.com/theupriser/steamify-cachyos.git cd steamify-cachyos ./steamify.sh ``` Run it as yourself, not as root. You'll see a checklist: ``` [x] SteamOS conversion: boot into gaming mode, Steam on the desktop (now: off) > [x] Install SteamOS theme: Vapor look (cachyos-vapor) (now: off) [x] Install Steam Deck/Machine icons: Deck button icons in gaming mode (now: off) [x] Single user mode: no password, lock screen or log out (SDDM) (now: off) Kernels (> = running; controller = Steam controller driver, LEDs = LED bar driver built) 6.18.52-1-cachyos-lts linux-cachyos-lts headers yes controller yes > 7.2.7-1-cachyos linux-cachyos headers yes controller yes Up/Down move Space select Enter run a run + re-apply what's on q quit ``` Move with the **arrow keys**, tick or untick with **Space** (on the **Boot into** row, **Left/Right** choose gamescope or desktop), and press **Enter** to run. "now:" shows what's on at the moment. Below the list, every installed kernel is shown with its headers and Steam controller driver; on a Steam Machine also whether the LED bar driver is built for it, and whether it's loaded right now, so a kernel update is easy to check. The wizard then shows what it will change, asks your password once, and at the end offers to restart (needed for changes to how the PC starts). After each run the menu comes back with the new state, so you can change more in one go; quit with **q**. When something needs a restart, you choose between going back to the menu and restarting now. Quitting then asks "Restart now? [Y/n]": **n** takes you back to the menu (and the next **q** asks again); Ctrl+C quits without restarting. Run it again whenever you like - to change your choices, to turn things off again, or after a CachyOS update (press `a` in the menu to re-apply everything that's on). If you cloned the repository, keep the whole folder: the script needs the files in `lib/` next to it. ## Using it - **To the desktop:** in gaming mode, open the Steam menu and choose **Power > Switch to Desktop**. - **Back to gaming mode:** double-click **Return to Gaming Mode** on the desktop (or log out, if you're not using single user mode). - After a restart you start in gaming mode, or on the desktop if you chose **Boot into: desktop** in the menu. Switching back and forth works the same either way. Prefer to start where you left off last time? Run one of these in Konsole (with **Boot into: gamescope**): ```bash steamos-session-select persistent # start where you left off last time steamos-session-select oneshot # always start in gaming mode (default) ``` ## If something goes wrong **Gaming mode shows a black screen or keeps restarting.** Press **Ctrl+Alt+F3**, log in with your username and password, and run: ```bash sudo /usr/lib/steamos/steam-set-session plasma.desktop && sudo systemctl restart display-manager ``` That takes you back to the desktop. **The LED bar on the Steam Machine stays dark.** Restart the PC once more; a freshly installed driver often needs a reboot. Still dark? See [Front LED bar](#front-led-bar-steam-machine) under technical details. **Undo something:** run the wizard again and untick it. --- ## Technical details ### How turning things on and off works At startup every component checks whether it is on (`*_status` in `lib/`). You choose; the wizard then turns off what you unticked (in reverse order) and turns on what you ticked. To be able to undo: - **System files** are backed up once, next to the original, with a `.bak-gamescope-wizard` suffix, and restored when you turn the component off. - **KDE settings** in your home directory are recorded with their previous value the first time the wizard changes them, in an undo journal under `~/.local/state/cachyos-gamescope-boot/`. Turning the component off writes the old values back (or removes keys that didn't exist before). Setups made by older versions of the script, without a journal, fall back to KDE's defaults. - **Packages** installed for the conversion (Steam, gamescope-session, ...) are kept when you turn it off; Steam Machine support removes its own. ### Single user mode: SDDM, no locking Turning it on switches to **SDDM** and turns off everything that asks for a password or another user, per user: `action/lock_screen`, `switch_user` and `start_new_session` restrictions in `kdeglobals`, no automatic locking (`kscreenlockerrc`), Meta+L and Ctrl+Alt+Del unbound, and the launcher shows only Sleep / Restart / Shut Down (kickoff `primaryActions=3`), which hides the Session dropdown with Log Out. (Restricting `action/logout` would also hide Restart and Shut Down.) Turning it off restores all of that and moves the conversion back to plasma-login-manager. **SDDM** is what SteamOS uses, and CachyOS's `steam-set-session` supports it directly: it writes `/etc/sddm.conf.d/zz-steamos-autologin.conf`, which SDDM honours. The script installs and enables `sddm` (active from the next boot), writes `User=`, `Session=` and `Relogin=true` to `/etc/sddm.conf.d/10-gamescope-autologin.conf`, and removes any `[Autologin]` from `/etc/sddm.conf` (read last, so it would override both). No sync bridge or sudoers rule is needed; the shortcut just runs `steamos-session-select gamescope`, which logs out, and `Relogin=true` logs straight back in to gamescope. Without single user mode, the conversion uses **plasma-login-manager** (CachyOS's default since March 2026), which needs the workarounds below. ### Why this is needed (plasma-login-manager) CachyOS's `gamescope-session-cachyos` package ships `steamos-session-select`, which is meant to work exactly like it does on real SteamOS. Since the March 2026 release, CachyOS uses `plasma-login-manager` instead of SDDM, and three things get in the way: 1. **No `User=` written to the autologin config.** `steam-set-session` (called by `steamos-session-select`) only writes a `Session=` key. `plasma-login-manager` needs both `Session=` and `User=` to autologin at all; without `User=` it shows the greeter every boot. 2. **Missing `/etc/plasmalogin.conf.d` directory.** Without it, `steam-set-session` fails, and Steam's "Switch to Desktop" hangs forever. *(Fixed upstream in `gamescope-session-cachyos` 1.1.6; the script still creates the directory for older versions.)* 3. **The base `/etc/plasmalogin.conf` wins over conf.d, and CachyOS ships it with `Session=plasma`.** Every tool that changes sessions (`steamos-session-select`, Steam's power menu, and `cachyos-gamescope-autologin.service`, which resets you to gamescope after a desktop session) only writes `/etc/plasmalogin.conf.d/zz-steamos-autologin.conf`. The base file takes priority, so none of those switches stick. The script sets `Session=`, `User=` and `Relogin=true` in the base config, and installs a small systemd path watcher that copies whatever CachyOS's tools write to the conf.d fragment into the base config. ### What each component changes **SteamOS conversion** (`lib/login-manager.sh`, `lib/steam-desktop.sh`, `lib/desktop-shortcut.sh`): - installs missing packages: `gamescope-session-cachyos`, `steam`, `mangohud`, `xterm`, `ttf-liberation`, `wqy-zenhei`, `plasma-keyboard`; - *SDDM (single user mode):* installs/enables SDDM and writes its autologin config; - *plasma-login-manager:* creates `/etc/plasmalogin.conf.d`, backs up and rewrites the `[Autologin]` section of `/etc/plasmalogin.conf`, removes stray `zzz-steamos-autologin*.conf` files from manual troubleshooting (never `zz-steamos-autologin.conf`, which CachyOS's tools own), and installs `/usr/local/bin/sync-steamos-session.sh` plus `sync-steamos-session.path`/`.service`; - `KWIN_IM_SHOW_ALWAYS=1` for the virtual keyboard and a `steam-desktop-autostart` systemd user service that starts Steam silently in Plasma only; - the **Return to Gaming Mode** shortcut; on plasma-login-manager with a narrow sudoers rule (`/etc/sudoers.d/gamescope-session-switch`) so it can restart the login manager without a password prompt. Turning it off restores `/etc/plasmalogin.conf` from its backup, removes the SDDM autologin, sync bridge, shortcut, sudoers rule and Steam autostart, and switches back to plasma-login-manager. **Steam Deck/Machine icons:** `STEAM_GAMEPADUI_ARGS="-gamepadui -steamos3"` in `~/.config/environment.d/` (and gamescope-session's own environment file), which makes Steam show Steam Deck button glyphs in gaming mode. ### SteamOS desktop look Installs CachyOS's `cachyos-vapor` package (the SteamOS Vapor theme the CachyOS handheld edition uses) from the CachyOS repository and switches your desktop to its Vapor global theme, including its desktop and window layout (like ticking "Desktop and window layout" in System Settings): Vapor colors and Plasma style, the SteamOS panel and launcher icon, and the Steam Deck wallpaper. Run it from the Plasma desktop: applying the layout needs a running Plasma session. It also adds the SteamOS desktop extras that `cachyos-vapor` doesn't ship, taken from the newest `steamdeck-kde-presets` on Valve's SteamOS mirror (checksum verified) and installed to `/usr/local`: - **Add to Steam** in the right-click menu of apps, AppImages and `.exe` files, and in the launcher: adds them to Steam as non-Steam games; - **Nested Desktop**: add it to Steam from the launcher, then start it in gaming mode for a Plasma desktop inside gaming mode; - the SteamOS **Return to Gaming Mode** icon (Steam logo with a return arrow); - a window rule that keeps the **Steam keyboard** above other windows; - an empty, password-less **KWallet**, only if you don't have a wallet yet, so nothing asks for a wallet password after autologin. Turning it off restores your previous look and panel layout, and removes `cachyos-vapor` again if the wizard installed it (and nothing else, like `cachyos-handheld`, needs it). ### Front LED bar (Steam Machine) The **Steam Machine support** component, only shown on Fremont hardware (DMI `Valve`/`Fremont`, or `OEM`/`F7F` on early units): - installs an AUR helper (`yay`) if neither `yay` nor `paru` is present; - installs the kernel headers for every installed kernel; - installs `leds-valve-dkms-git` from the AUR - Valve's own driver from the SteamOS kernel - builds it for every installed kernel (so the LTS kernel works too), and loads it at every boot (`/etc/modules-load.d/leds-valve.conf`); - adds a udev rule (`/etc/udev/rules.d/70-valve-leds-user.rules`) that gives your user the LED files, so Steam, which runs as you, can drive the bar; - console-like power button: it puts the machine to sleep, and it never suspends by itself on mains power (the launcher's Shut Down still shuts down); - installs and enables `steamos-manager`, the service Steam in gaming mode uses for hardware settings (fan, HDMI-CEC, performance); it recognises the Steam Machine from its DMI data. Turning it off removes all of that again (the AUR helper is kept). The LEDs appear as `/sys/class/leds/valve-leds*`. The driver's Makefile builds against the running kernel (`uname -r`) instead of the kernel DKMS builds for, so the wizard adds a DKMS override (`/etc/dkms/leds-valve-dkms.conf`) that passes DKMS's target kernel in. With it, DKMS rebuilds the driver whenever a kernel or its headers are installed or upgraded. A newly added kernel doesn't come with its headers, so `ensure-kernel-headers.service` checks at every boot and installs any missing `-headers` package, which makes DKMS build the driver for it. Troubleshooting: ```bash dkms status ls -l /sys/class/leds/valve-leds*/ sudo dmesg | grep -i valve cat /var/lib/dkms/leds-valve-dkms/0.1/build/make.log journalctl --user -b | grep -i led ``` ### BIOS updates (Steam Machine) The **Update BIOS** item is only shown on a Steam Machine and is never ticked by default. It shows the BIOS version you have now and the newest one Valve ships (the `.cab` file in its `fremont-hw-support` package, looked up on Valve's SteamOS mirror): ``` [ ] Update BIOS: now F7F0107, newest F7F0108 (own risk) (opt-in, runs once) ``` It can only be ticked when Valve has a newer BIOS than yours; when you're up to date, when the newest version can't be looked up (offline), or when an update is already waiting for a restart, it's greyed out. When you run it, the wizard: 1. downloads Valve's package and checks its **SHA-256** against Valve's repository, so it's exactly Valve's file; 2. asks **fwupd** whether the firmware is for this very machine (fwupd compares the firmware's hardware IDs with the device) and stops if it isn't; 3. shows a large red **warning** with the current and the new version, and asks whether you understand the risks (default: no); 4. shows the warning **again** and only continues when you type `UPDATE`; 5. hands the firmware to fwupd, which writes it during the **next restart**: choose "restart now" or restart later yourself. **At your own risk:** a failed or interrupted BIOS update can leave the machine unable to start. Keep it on mains power, and never turn off the power, unplug it or press the power button while it updates, including during the restart; the screen can stay black for several minutes. To walk through it without flashing anything, run the wizard with `WIZARD_BIOS_DRY_RUN=1`: it downloads and checks the package and shows both warnings, skips fwupd's device check, and only prints the install command. ### Manual session control ```bash steamos-session-select gamescope # switch to gamescope right now steamos-session-select plasma # switch to desktop right now steamos-session-select persistent # remember the last-used session across reboots steamos-session-select oneshot # always start in gamescope (default, like a Deck) ``` With `Relogin=true`, a gamescope session that fails to start is restarted immediately, which can turn into a loop - hence the Ctrl+Alt+F3 escape above. ### Removing everything Run the wizard and untick everything. Afterwards the PC boots to the normal CachyOS login screen again; packages installed for the conversion (Steam, gamescope-session, ...) stay installed. ### Project layout | File | Responsibility | |---|---| | `steamify.sh` | Entry point: checks, menu, apply, summary, restart | | `lib/menu.sh` | The menu: detect, toggle, plan and apply changes | | `lib/state.sh` | Undo journal for KDE settings (`kset`/`krevert`) | | `lib/common.sh` | Output helpers, prompts, backups, plasmashell handling | | `lib/packages.sh` | Required packages, AUR helper (yay/paru) | | `lib/boot-session.sh` | Boot into gamescope or the desktop (`steamify-boot-desktop.service`) | | `lib/login-manager.sh` | SteamOS conversion: SDDM or plasmalogin autologin, sync bridge | | `lib/steam-desktop.sh` | Steam in the Plasma session; Steam Deck/Machine icons | | `lib/desktop-shortcut.sh` | Return to Gaming Mode shortcut and its sudoers rule | | `lib/vapor-theme.sh` | SteamOS theme: installs and switches to `cachyos-vapor` | | `lib/steamos-extras.sh` | SteamOS desktop extras from Valve's package (Add to Steam, Nested Desktop, icon, keyboard rule, KWallet) | | `lib/single-user.sh` | Single user mode: no lock screen, user switching or log out | | `lib/wizard-shortcut.sh` | Steamify shortcut: desktop icon and launcher entry that run the newest release | | `lib/bios.sh` | Update BIOS (Steam Machine, opt-in): current/newest version, double confirmation, fwupd | | `lib/steam-machine.sh` | Steam Machine support: LED driver, LED access, steamos-manager | | `.github/tools/bundle.sh` | Builds the single-file version (`dist/steamify.sh`) | | `.github/workflows/bundle.yml` | Builds and checks it on every push; publishes it on `main` | The single-file version is generated: on every push to `main`, GitHub Actions runs `.github/tools/bundle.sh`, checks the result with `bash -n` and shellcheck, and publishes it as a release per version (tag `v`, never overwritten; the newest is marked latest, and the `latest` tag follows it). It inlines `lib/*.sh` and wraps the entry point in `main()`, so bash has read the whole file before anything runs; when stdin is a pipe (`curl | bash`) it reattaches the terminal for the menu (set `WIZARD_KEEP_STDIN=1` to keep piped input). Notes for contributors and AI coding agents are in [`AGENTS.md`](AGENTS.md). ### Caveats - This works around CachyOS/`plasma-login-manager` behavior as of September 2026. If CachyOS fixes `steam-set-session` upstream, parts of this script become unnecessary - please open an issue or PR if you notice that. - Tested on a Valve Steam Machine running CachyOS Desktop edition. It should work on any CachyOS desktop install using `plasma-login-manager`, but hasn't been tested on Steam Deck/Legion Go hardware. ### Related upstream reports - [CachyOS/gamescope-session#9](https://github.com/CachyOS/gamescope-session/issues/9) - "Switch to Desktop" hang due to missing `/etc/plasmalogin.conf.d` ## License MIT - do whatever you want with it.