### List of Package Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of defining an option that accepts a list of Nix packages.

```nix
jovian.decky-loader.extraPackages = [ pkgs.curl pkgs.unzip ]
```

--------------------------------

### NixOS Service Dependencies Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Example of configuring service dependencies in NixOS, ensuring services start in the correct order. This snippet shows 'gamescope-session' depending on 'inputplumber.service'.

```nix
systemd.services.gamescope-session = {
  wantedBy = [ "multi-user.target" ];
  after = [ "inputplumber.service" ];
};
```

--------------------------------

### Function to List of Packages Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of a function that accepts a Python package set and returns a list of packages.

```nix
jovian.decky-loader.extraPythonPackages = pythonPackages: with pythonPackages; [ hid ]
```

--------------------------------

### Attribute Set of String Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of defining an option that accepts an attribute set of strings for environment variables.

```nix
jovian.steam.environment = { VAR1 = "value1"; VAR2 = "value2"; }
```

--------------------------------

### Start Gamescope Session

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/configuration.md

Alternative method to start the Steam Deck UI by running this command in a VT. Note that the "Switch to Desktop" option will close Steam when used this way.

```bash
start-gamescope-session
```

--------------------------------

### Type Composition Examples

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Provides examples of composing NixOS types to create more complex type signatures. This includes creating lists of attribute sets, nullable functions, and unions of types.

```nix
# List of attribute sets of strings
type = types.listOf (types.attrsOf types.str);

# Nullable function returning list
type = types.nullOr (types.functionTo (types.listOf types.str));

# Enum or string
type = types.enum [ "a" "b" ] // types.str;
```

--------------------------------

### Apply Security Capabilities to Gamescope Wrapper

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Demonstrates how to use security.wrappers to apply specific capabilities, like cap_sys_nice, to an executable, using Gamescope as an example.

```nix
security.wrappers.gamescope = {
  owner = "root";
  source = "${pkgs.gamescope}/bin/gamescope";
  capabilities = "cap_sys_nice+pie";
};
```

--------------------------------

### Nullable String Type Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of a nullable string type for `jovian.steam.desktopSession`, allowing `null` or a string.

```nix
jovian.steam.desktopSession = types.nullOr types.str;
```

--------------------------------

### Autostart Steam Deck UI

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/configuration.md

Set this option to true to automatically start the Steam Deck UI at boot. This also enables the "Switch to Desktop" option.

```nix
jovian.steam.autoStart = true;
```

--------------------------------

### Path Type Usage

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Use `types.path` for filesystem paths. Example shows setting a state directory.

```nix
jovian.decky-loader.stateDir = "/var/lib/decky-loader"
```

--------------------------------

### Force Kernel Parameters

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Illustrates that options set with mkForce cannot be overridden, using kernel parameters as an example.

```nix
# These cannot be changed after being set:
boot.kernelParams = mkForce [ "custom=param" ];
```

--------------------------------

### String to Path Coercion Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Demonstrates that a string literal can be coerced into a path type.

```nix
# Both are equivalent:
stateDir = "/var/lib/decky-loader";
stateDir = /var/lib/decky-loader;
```

--------------------------------

### Set Desktop Session

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Define the session to launch for Desktop Mode. Set to `"gamescope-wayland"` to return to Gaming Mode. Ensure the specified session is installed.

```nix
jovian.steam.desktopSession = "plasma";
```

```nix
jovian.steam.desktopSession = "gamescope-wayland";
```

--------------------------------

### Enable Decky Loader

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/in-depth/decky-loader.md

Add this configuration to your NixOS setup to enable Decky Loader.

```nix
{ config, pkgs, ... }:

{
  jovian.decky-loader = {
    enable = true;
  };
}
```

--------------------------------

### String Type Usage

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Use `types.str` for string options. Examples show setting user and desktop session names.

```nix
jovian.steam.user = "deck"
```

--------------------------------

### Configure Steam Deck UI

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/configuration.md

Enable and configure the Steam Deck UI (Gamescope session). This example enables the UI, sets it to auto-start, specifies the user and desktop session, and defines custom environment variables for the Gamescope session.

```nix
jovian.steam = {
  enable = true;
  autoStart = true;
  user = "deck";
  desktopSession = "plasma";
  environment = {
    STEAM_COMPAT_TOOL_PATHS = "/home/deck/.steam/compatibilitytools.d";
  };
};
```

--------------------------------

### Zram Swap Configuration Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steamos.md

Configures compressed in-memory swap using zram. This snippet sets zram to be enabled, with a higher priority than disk swap, using 50% of system RAM, and the zstd compression algorithm.

```nix
zramSwap = {
  enable = true;
  priority = 100;
  memoryPercent = 50;
  algorithm = "zstd";
};
```

--------------------------------

### Enable All SteamOS Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steamos.md

This is the recommended approach to enable all SteamOS-related configurations provided by the Jovian module. It simplifies setup by activating multiple optimizations at once.

```nix
jovian.steamos.useSteamOSConfig = true;
```

--------------------------------

### Enum Type Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of an enum type for the steam updater splash screen, with valid values listed.

```nix
jovian.steam.updater.splash = types.enum [ "steamos" "jovian" "bgrt" "vendor" ];
```

--------------------------------

### Package Type Usage

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Use `types.package` for Nix package derivations. Example shows assigning a package.

```nix
jovian.decky-loader.package = pkgs.decky-loader
```

--------------------------------

### Set Custom Environment Variables for Steam

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Apply custom environment variables before the Steam session starts. Variables are written to `/etc/xdg/gamescope-session/environment` at build time.

```nix
jovian.steam.environment.MYVAR = "value";
```

--------------------------------

### Auto-Launch Gaming Mode

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Automatically boots into Gaming Mode as the 'deck' user with Plasma Wayland as the desktop alternative. Ensures Steam starts on system boot.

```nix
jovian.steam = {
  enable = true;
  autoStart = true;
  user = "deck";
  desktopSession = "plasmawayland";
};
```

--------------------------------

### Auto-Launch Gaming Mode

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

Configures Steam to automatically start in gaming mode with a specified user and desktop session. Requires Jovian NixOS modules to be imported.

```nix
{ 
  imports = [ 
    <jovian-nixos/modules>
  ];

  jovian.devices.steamdeck.enable = true;
  jovian.steam = { 
    enable = true;
    autoStart = true;
    user = "deck";
    desktopSession = "plasmawayland";
  };
}
```

--------------------------------

### Implicit List Coercion Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Shows that a single value might be implicitly coerced into a list in certain contexts.

```nix
# Might be coerced to: 
kernelModules = "hid_nintendo";  # -> [ "hid_nintendo" ]
```

--------------------------------

### Usage in Nix Flake with Flake Input

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Example of using Jovian NixOS within a Nix flake by referencing its flake input.

```nix
{
  inputs.jovian.url = "github:Jovian-Experiments/Jovian-NixOS";
  
  outputs = { self, jovian, ... }: {
    nixosConfigurations.myhost = {
      modules = [
        jovian.nixosModules.default
      ];
    };
  };
}
```

--------------------------------

### Add Python 3 to Extra Packages for External Commands

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/decky-loader.md

Example of adding the python3 package to `extraPackages` to ensure plugins can access external Python commands.

```nix
jovian.decky-loader.extraPackages = [ pkgs.python3 ];
```

--------------------------------

### Configure Udev Rule for Uinput Device

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Provides an example of a udev rule to grant access to the uinput device for unprivileged users in the 'users' group.

```udev
KERNEL=="uinput", SUBSYSTEM=="misc", TAG+="uaccess"
```

--------------------------------

### Jovian NixOS with Flake Input

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

Integrates Jovian NixOS using a flake input for managing dependencies. This example shows how to include the default NixOS modules from the Jovian flake.

```nix
{ 
  inputs.jovian.url = "github:Jovian-Experiments/Jovian-NixOS";
  
  outputs = { self, jovian, ... }:
  {
    nixosConfigurations.myhost = {
      modules = [
        jovian.nixosModules.default
        # ... your config
      ];
    };
  };
}
```

--------------------------------

### Custom Validation Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Demonstrates custom validation using `lib.assertMsg` to ensure an option's value meets specific criteria beyond basic type checking. This is useful for enforcing complex business logic or constraints.

```nix
assert lib.assertMsg 
  (desktopSession == null || builtins.elem desktopSession sessionNames)
  "Desktop session must be a valid installed session";
```

--------------------------------

### Configure Steam Updater Splash Screen

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/configuration.md

Customize the splash screen used by the Steam updater. This example sets the splash screen to use the Jovian Experiments logo.

```nix
jovian.steam.updater.splash = "jovian";
```

--------------------------------

### Union Type with Custom Validation Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Example of a union type for `jovian.steam.desktopSession` that is nullable string or passes a custom check function.

```nix
jovian.steam.desktopSession = with types; nullOr str // {
  check = session: 
    session == null || builtins.elem session sessionNames;
};
```

--------------------------------

### Troubleshooting Module Loading: Correct Module Path

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Illustrates the correct way to import Jovian modules, emphasizing importing the directory rather than a specific file.

```nix
# Correct:
imports = [ "${jovian}/modules" ];

# Wrong:
imports = [ "${jovian}/modules/steam" ];  # Points to a file, not a directory

```

--------------------------------

### Configure AutoStart User

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Specify the local system user for automatic Steam Deck UI login. This user must exist on the system. This setting is required when `autoStart` is enabled.

```nix
jovian.steam.user = "deck";
```

--------------------------------

### Steam with Environment Customization

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Enables Steam and auto-start, while setting custom environment variables for compatibility tools and VKD3D memory allocation.

```nix
jovian.steam = {
  enable = true;
  autoStart = true;
  user = "deck";
  environment = {
    STEAM_COMPAT_TOOL_PATHS = "/home/deck/.steam/compatibilitytools.d";
    VKD3D_MEMORY_ALLOCATOR = "device";
  };
};
```

--------------------------------

### Boolean Type Usage

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Use `types.bool` for boolean options. Example shows enabling a feature.

```nix
jovian.devices.steamdeck.enable = true
```

--------------------------------

### Enable Early Modesetting with AMDGPU Firmware

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Shows how to enable early modesetting by including the amdgpu kernel module in the initrd and setting hardware.enableRedistributableFirmware.

```nix
hardware.enableRedistributableFirmware = true;
boot.initrd.kernelModules = [ "amdgpu" ];
```

--------------------------------

### Enable Steam Deck Hardware Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/devices/valve-steam-deck/index.md

Import local modules and enable Steam Deck hardware configurations in your system settings.

```nix
jovian.devices.steamdeck.enable = true;
```

--------------------------------

### Type Validation Error Example

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Illustrates the error message produced when a value does not match the declared option type.

```text
error: The option `jovian.steam.autoStart` is not of type boolean.
```

--------------------------------

### Auto-Start Gaming Mode

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/steam.md

Configure the system to automatically launch Gaming Mode on boot. This also enables desktop switching to Plasma 6 and specifies the user and desktop session for Steam.

```nix
{
  services.desktopManager.plasma6.enable = true;

  jovian.steam = {
    enable = true;
    autoStart = true;
    user = "yourname";
    desktopSession = "plasma";
  };
}
```

--------------------------------

### Basic Steam Enablement

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

Enables Steam functionality. Requires launching via a display manager or the 'start-gamescope-session' command.

```nix
jovian.steam = {
  enable = true;
};
```

--------------------------------

### List of Type Declaration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Declares a list where all elements must be of a specified type `T`. Usage example shows a list of packages.

```nix
listOf (T: type) -> type
```

--------------------------------

### Configure Desktop Session for Switch to Desktop

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/configuration.md

Configure the name of the X11 or Wayland session to switch to when using the "Switch to Desktop" option. The semantics are the same as for the `services.displayManager.defaultSession` NixOS option.

```nix
jovian.steam.desktopSession = "your-session-name";
```

--------------------------------

### Verify Systemd Service Dependencies

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Checks the dependencies and validity of a systemd service. Helps diagnose services that are not starting correctly.

```bash
systemd-analyze verify gamescope-session
```

--------------------------------

### Importing Selective Jovian Modules

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Demonstrates how to import specific Jovian modules, though this approach is generally not recommended due to potential dependency chain breakage.

```nix
{ imports = [
    /path/to/jovian-nixos/modules/steam
    /path/to/jovian-nixos/modules/hardware
    # Don't import decky-loader
  ];
  
  jovian.steam.enable = true;
}

```

--------------------------------

### Nullable Type Declaration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Declares a type that can be either of type `T` or `null`. Usage example shows a nullable string for desktop session.

```nix
nullOr (T: type) -> type
```

--------------------------------

### Enable Decky Loader with Extra Tools

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/decky-loader.md

Enables Decky Loader and adds curl, unzip, and wget to the service's PATH.

```nix
jovian.decky-loader = {
  enable = true;
  extraPackages = [ pkgs.curl pkgs.unzip pkgs.wget ];
};
```

--------------------------------

### Enable Early Modesetting for AMD GPUs

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/hardware.md

Enables early kernel modesetting by loading the 'amdgpu' driver in the initrd. This provides a graphical boot experience. Requires redistributable firmware.

```nix
boot.initrd.kernelModules = [ "amdgpu" ];
hardware.enableRedistributableFirmware = true;
```

--------------------------------

### Check Steam Session Journal Logs

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

View the last 50 lines of the gamescope-session journal to troubleshoot Steam startup issues.

```bash
journalctl -u gamescope-session -n 50
```

--------------------------------

### Troubleshooting Module Loading: Correct Option Namespace

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Shows the correct namespace for Jovian module options, highlighting the need for specific sub-namespaces like 'devices'.

```nix
# Correct:
jovian.devices.steamdeck.enable = true;

# Wrong:
jovian.steamdeck.enable = true;  # Missing 'devices' namespace

```

--------------------------------

### Enum Type Declaration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Declares an enum type, restricting values to a predefined list of strings. Usage example shows valid splash screen options.

```nix
enum (values: list of strings) -> type
```

--------------------------------

### NixOS Module Definition Pattern

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Demonstrates the standard NixOS module system pattern used by Jovian modules, including option definition and conditional configuration.

```nix
{ config, lib, pkgs, ... }:

let
  inherit (lib)
    mkIf
    mkMerge
    mkOption
    types
  ;
  cfg = config.jovian.module_name;
in
{
  options = {
    jovian.module_name = {
      enable = mkOption {
        type = types.bool;
        default = false;
        description = "...";
      };
      
      option2 = mkOption {
        type = types.str;
        default = "value";
        description = "...";
      };
    };
  };
  
  config = mkIf cfg.enable {
    # Apply configuration when module is enabled
  };
}

```

--------------------------------

### Enable Decky Loader

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/decky-loader.md

Basic configuration to enable the Steam Deck Plugin Loader service.

```nix
jovian.decky-loader.enable = true;
```

--------------------------------

### Attribute Set of Type Declaration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Declares an attribute set (key-value map) where all values must be of a specified type `T`. Usage example shows an attribute set of strings.

```nix
attrsOf (T: type) -> type
```

--------------------------------

### Check SteamOS Manager Journal Logs

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/steam.md

View the last 50 lines of the steamos-manager journal to troubleshoot Steam startup issues.

```bash
journalctl -u steamos-manager -n 50
```

--------------------------------

### Usage in Nix Flake with Local Path

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Shows how to integrate Jovian NixOS into a Nix flake using a local path reference.

```nix
{
  inputs.jovian = {
    url = "path:./jovian-nixos";
    flake = false;
  };
  
  outputs = { self, jovian, ... }: {
    nixosConfigurations.myhost = {
      modules = [
        "${jovian}/modules"
      ];
    };
  };
}
```

--------------------------------

### Enable SteamOS Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/configuration.md

Enables a comprehensive set of SteamOS-like configurations for a more authentic SteamOS experience. This includes Bluetooth, auto-mount, HDMI-CEC, early OOM, default kernel command lines, product serial access, and zram.

```nix
jovian.steamos = {
  useSteamOSConfig = true;
  enableBluetoothConfig = true;
  enableAutoMountUdevRules = true;
  enableHdmiCecIntegration = true;
  enableEarlyOOM = true;
  enableDefaultCmdlineConfig = true;
  enableProductSerialAccess = true;
  enableZram = true;
};
```

--------------------------------

### Steam Deck with Auto-Start Gaming Mode

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/configuration.md

Configures Steam Deck with automatic startup of Steam in gaming mode. Specifies the user and desktop session for Steam.

```nix
{ 
  jovian.devices.steamdeck.enable = true;
  jovian.steam = {
    enable = true;
    autoStart = true;
    user = "deck";
    desktopSession = "plasmawayland";
  };
  jovian.steamos.useSteamOSConfig = true;
}
```

--------------------------------

### Set System-Wide Environment Variable

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Demonstrates how to set a system-wide environment variable using the environment.variables option.

```nix
environment.variables = {
  STEAM_ALLOW_DRIVE_UNMOUNT = "1";
};
```

--------------------------------

### Enable Steam Deck with Decky Loader

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Configure a Steam Deck with Decky Loader support, including extra Python packages for plugins.

```nix
{ imports = [ jovian.nixosModules.default ];
  
  jovian.devices.steamdeck.enable = true;
  jovian.steam.enable = true;
  jovian.decky-loader = {
    enable = true;
    extraPythonPackages = pythonPackages: with pythonPackages; [
      hid pyusb
    ];
  };
}

```

--------------------------------

### Importing Jovian NixOS Modules via Local Path

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Demonstrates importing Jovian NixOS modules directly from a local path in your NixOS configuration.

```nix
{
  imports = [
    (import /path/to/jovian-nixos/modules)
  ];

  jovian.devices.steamdeck.enable = true;
}
```

--------------------------------

### Enable Desktop Gaming PC Support

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Configure a non-Deck AMD GPU system with Steam support. Ensures early modesetting for AMD GPUs and enables Steam.

```nix
{ imports = [ jovian.nixosModules.default ];
  
  jovian.hardware.has.amd.gpu = true;
  jovian.hardware.amd.gpu.enableEarlyModesetting = true;
  jovian.steam.enable = true;
  jovian.steamos.useSteamOSConfig = true;
}

```

--------------------------------

### Minimal Server with Kernel Optimization Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

This minimal server configuration enables Jovian's SteamOS-related kernel optimizations, including default command line configuration, ZRAM, and early Out-Of-Memory (OOM) killer.

```nix
{
  imports = [ jovian.nixosModules.default ];
  
  jovian.steamos = {
    enableDefaultCmdlineConfig = true;
    enableZram = true;
    enableEarlyOOM = true;
  };
}
```

--------------------------------

### Override Default Steam Deck Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Demonstrates how to enable Steam Deck devices and disable vendor drivers by overriding default mkDefault options.

```nix
{
  imports = [ jovian.nixosModules.default ];
  
  jovian.devices.steamdeck.enable = true;
  jovian.devices.steamdeck.enableVendorDrivers = false;  # Override default
}
```

--------------------------------

### Initialize Pagefind UI

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/support/docs/search.md

Initializes the Pagefind UI component within a specified HTML element. Configure element, base URL, image display, and translations.

```javascript
window.addEventListener('DOMContentLoaded', (event) => {
	pagefind = new PagefindUI({
		element: "#search",
		baseUrl: document.baseURI.replace(/search.html/, ""),
		showImages: false,
		translations: {
			placeholder: "",
		},
	});
    // Workaround for the lack of an autofocus option.
    window.setTimeout(function () {
        document.querySelector(".pagefind-ui__search-input").focus();
    }, 1);
});
```

--------------------------------

### NixOS Conditional Module Loading

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Illustrates conditional configuration application in NixOS modules using mkIf. The configuration block is only applied when the specified condition (e.g., cfg.enableVendorDrivers) is true.

```nix
config = mkIf cfg.enableVendorDrivers {
  # Only applied when enabled
};
```

--------------------------------

### Enable Steam Deck UI

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/configuration.md

Set this option to true to enable the Steam Deck UI tooling. This does not enable "desktop" Steam.

```nix
jovian.steam.enable = true;
```

--------------------------------

### Load AMDGPU Driver in Initrd

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/hardware.md

Ensure the amdgpu kernel module is loaded in the initrd when early modesetting is enabled. This automatically includes necessary firmware files for the amdgpu driver.

```nix
boot.initrd.kernelModules = [ "amdgpu" ];
```

--------------------------------

### Enable Decky Loader with Custom State Directory

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/decky-loader.md

Enables Decky Loader and configures a custom directory for storing plugins and data.

```nix
jovian.decky-loader = {
  enable = true;
  stateDir = "/mnt/games/decky-plugins";
};
```

--------------------------------

### Enable Steam Client

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/steam.md

Enable the Steam Deck version of the Steam client by setting `jovian.steam.enable` to true.

```nix
{
  jovian.steam.enable = true;
}
```

--------------------------------

### Enable Decky Loader with Custom User and State Directory

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/decky-loader.md

Enables Decky Loader, specifies a custom unprivileged user ('steam'), and a corresponding state directory. Assumes the 'steam' user is configured elsewhere.

```nix
jovian.decky-loader = {
  enable = true;
  user = "steam";
  stateDir = "/home/steam/.decky-loader";
};

users.users.steam = {
  # ... user config
};
```

--------------------------------

### Minimal Jovian NixOS Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Enables basic Steam Deck support with the minimal required configuration.

```nix
{
  imports = [ jovian.nixosModules.default ];
  
  jovian.devices.steamdeck.enable = true;
}
```

--------------------------------

### Review Current Kernel Parameters

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Displays the active kernel command line parameters on the system.

```bash
cat /proc/cmdline
```

--------------------------------

### Set Session Environment Variables

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Shows how to set environment variables for the Gamescope session by exporting them in a shell script.

```bash
export STEAM_ALLOW_DRIVE_UNMOUNT="1"
export CUSTOM_VAR="value"
```

--------------------------------

### Enable Steam Deck with Firmware Auto-Updates

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/devices-steamdeck.md

Enables Steam Deck support and configures automatic updates for BIOS and controller firmware.

```nix
jovian.devices.steamdeck = {
  enable = true;
  autoUpdate = true;  # Auto-update BIOS and controller
  enableFwupdBiosUpdates = true;
};
```

--------------------------------

### Jovian NixOS Configuration Namespace

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Demonstrates the top-level 'jovian' key for configuring Jovian NixOS options within NixOS configuration.

```nix
{
  jovian = {
    # Module options go here
  };
}
```

--------------------------------

### Minimal Steam Deck Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

Enables basic Steam Deck support and Steam integration. Ensure Jovian NixOS modules are imported.

```nix
{ 
  imports = [ 
    <jovian-nixos/modules>  # or via flake input
  ];

  jovian.devices.steamdeck.enable = true;
  jovian.steam.enable = true;
  jovian.steamos.useSteamOSConfig = true;
}
```

--------------------------------

### Inspect Generated Jovian Configuration Files

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Displays the content of generated configuration files for Xorg and Gamescope session.

```bash
cat /etc/X11/xorg.conf.d/90-jovian.conf
cat /etc/xdg/gamescope-session/environment
```

--------------------------------

### Set Per-Service Environment Variable

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Illustrates how to set an environment variable for a specific service, such as decky-loader, using its .serviceConfig.Environment.

```nix
systemd.services.decky-loader.environment = {
  UNPRIVILEGED_USER = "decky";
};
```

--------------------------------

### Enable Redistributable AMD GPU Firmware

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/hardware.md

Set this option to true to allow legally redistributable AMD GPU firmware to be loaded. This is often provided by pkgs.linux-firmware or pkgs.linux-firmware-jupiter.

```nix
hardware.enableRedistributableFirmware = true;
```

--------------------------------

### Importing Jovian NixOS Modules via Flake

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

Shows how to import the Jovian NixOS module system using a flake input in your NixOS configuration.

```nix
# In your flake.nix:
inputs.jovian.url = "github:Jovian-Experiments/Jovian-NixOS";

# In your NixOS configuration:
{
  imports = [
    inputs.jovian.nixosModules.default
  ];

  # Configure via the jovian namespace
  jovian = {
    devices.steamdeck.enable = true;
    steam.enable = true;
  };
}
```

--------------------------------

### Verify AMDGPU Firmware Availability

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/hardware.md

Check if the necessary firmware files for the amdgpu driver are present in the system's firmware directory. This is crucial for early modesetting to function correctly.

```bash
ls /lib/firmware/amdgpu/
```

--------------------------------

### Basic Option Definition with Type

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/types.md

Defines a basic option `enable` with a boolean type constraint.

```nix
options.jovian.devices.steamdeck = {
  enable = mkOption {
    type = types.bool;
    default = false;
    description = "...";
  };
};
```

--------------------------------

### Apply Optimized Kernel Parameters for Steam Deck

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/devices-steamdeck.md

Enables Steam Deck command line flags to apply optimized kernel parameters for the hardware.

```text
spi_amd.speed_dev=1
```

--------------------------------

### Perform NixOS Dry Run for Configuration Errors

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Simulates a NixOS rebuild to identify potential configuration errors, such as unknown options. Useful for troubleshooting module imports.

```bash
nixos-rebuild dry-run
```

--------------------------------

### Desktop Gaming PC with Steam Configuration

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

This configuration sets up a desktop gaming PC with Steam, enabling AMD GPU features like early modesetting and backlight control, and configuring Steam compatibility tool paths.

```nix
{
  imports = [ jovian.nixosModules.default ];
  
  # Configure hardware manually
  jovian.hardware.has.amd.gpu = true;
  jovian.hardware.amd.gpu.enableEarlyModesetting = true;
  jovian.hardware.amd.gpu.enableBacklightControl = true;
  
  jovian.steam = {
    enable = true;
    environment = {
      STEAM_COMPAT_TOOL_PATHS = "/home/user/.steam/compatibilitytools.d";
    };
  };
  
  jovian.steamos.useSteamOSConfig = true;
}
```

--------------------------------

### Enable Decky Loader with Custom Packages

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/configuration.md

Enables the Steam Deck Plugin Loader and includes custom packages for the service PATH and Python environment. Specifies the data directory and the user for running plugins.

```nix
jovian.decky-loader = {
  enable = true;
  extraPackages = [ pkgs.curl pkgs.unzip ];
  extraPythonPackages = pythonPackages: with pythonPackages; [ hid ];
  stateDir = "/var/lib/decky-loader";
  user = "decky";
};
```

--------------------------------

### Configure Polkit Rule for NetworkManager

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/integration.md

Allows users to perform privileged NetworkManager actions without a password. Applied via security.polkit.extraConfig.

```javascript
polkit.addRule(function(action, subject) {
  if (action.id.indexOf("org.freedesktop.NetworkManager") == 0) {
    return polkit.Result.YES;
  }
});
```

--------------------------------

### Update Steam Deck Docking Station Firmware

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/docs/devices/valve-steam-deck/index.md

Connect the dock via USB-C and run this command to update its firmware.

```bash
jupiter-dock-updater
```

--------------------------------

### Module Dependencies

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

Illustrates the dependency relationships between Jovian NixOS modules. Enabling a parent module typically enables its sub-modules.

```text
devices/steamdeck → hardware/amd
steam ← devices/steamdeck
steamos ← steam
```

--------------------------------

### Jovian NixOS Main Module Import

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/api-reference/module-overview.md

The root module 'modules/default.nix' that imports all other submodules, required for enabling Jovian NixOS.

```nix
{
  imports = [
    ./decky-loader.nix
    ./devices
    ./jovian
    ./hardware
    ./steam
    ./steamos
  ];
}
```

--------------------------------

### File Structure of Jovian NixOS Repository

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

This snippet displays the directory structure of the Jovian NixOS repository, illustrating the organization of modules and documentation.

```tree
jovian-nixos/
├── README.md
├── flake.nix
├── overlay.nix
├── modules/
│   ├── default.nix
│   ├── decky-loader.nix
│   ├── devices/
│   │   ├── default.nix
│   │   └── steamdeck/
│   │       ├── controller.nix
│   │       ├── fan-control.nix
│   │       ├── firmware.nix
│   │       ├── graphical.nix
│   │       ├── hw-support.nix
│   │       ├── kernel.nix
│   │       ├── perf-control.nix
│   │       ├── sdgyrodsu.nix
│   │       ├── sound.nix
│   │       └── workarounds.nix
│   ├── hardware/
│   │   ├── default.nix
│   │   └── amd/
│   │       └── default.nix
│   ├── jovian/
│   │   ├── overlay.nix
│   │   └── workarounds.nix
│   ├── steam/
│   │   ├── autostart.nix
│   │   ├── default.nix
│   │   ├── environment.nix
│   │   ├── steam.nix
│   │   └── updater.nix
│   └── steamos/
│       ├── automount.nix
│       ├── bluetooth.nix
│       ├── boot.nix
│       ├── cec.nix
│       ├── default.nix
│       ├── earlyoom.nix
│       ├── misc.nix
│       └── sysctl.nix
└── docs/
    ├── getting-started.md
    ├── configuration.md
    └── ...
```

--------------------------------

### Configuration Namespaces

Source: https://github.com/jovian-experiments/jovian-nixos/blob/development/_autodocs/README.md

Lists the top-level configuration namespaces within Jovian NixOS, including their sub-options and types. Refer to the Configuration Reference for full details.

```nix
config.jovian.{
  decky-loader.{
    enable          # bool
    package         # package
    extraPackages   # [package]
    extraPythonPackages  # function
    stateDir        # path
    user            # string
  }
  
  devices.steamdeck.{
    enable
    enableControllerUdevRules
    enableOsFanControl
    enableXorgRotation
    enableVendorDrivers
    enableDefaultCmdlineConfig
    enableDefaultStage1Modules
    enableKernelPatches
    enablePerfControlUdevRules
    autoUpdate
    enableFwupdBiosUpdates
  }
  
  hardware.has.amd.gpu
  hardware.amd.gpu.{
    enableEarlyModesetting
    enableBacklightControl
  }
  
  steam.{
    enable
    autoStart
    user
    desktopSession
    environment
    updater.splash
  }
  
  steamos.{
    useSteamOSConfig
    enableBluetoothConfig
    enableAutoMountUdevRules
    enableHdmiCecIntegration
    enableEarlyOOM
    enableDefaultCmdlineConfig
    enableProductSerialAccess
    enableZram
  }
}
```