Add NixOS kiosk flake and config

flake.nix

@@ -0,0 +1,29 @@
+{
+  description = "Kiosk NixOS ISO with Firefox in kiosk mode";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
+    flake-utils.url = "github:numtide/flake-utils";
+    nixos-generators.url = "github:nix-community/nixos-generators";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, nixos-generators }:
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = import nixpkgs { inherit system; };
+    in {
+      # Build a bootable ISO image using nixos-generators
+      packages.iso = nixos-generators.nixosGenerate {
+        inherit pkgs;
+        format = "iso";
+        modules = [ ./nixos/kiosk.nix ];
+      };
+
+      # Expose the NixOS configuration for direct use if desired
+      nixosConfigurations.kiosk = let
+        lib = nixpkgs.lib;
+      in lib.nixosSystem {
+        system = "x86_64-linux";
+        modules = [ ./nixos/kiosk.nix ];
+      };
+    });
+}

nixos/kiosk.nix

@@ -0,0 +1,140 @@
+{ config, pkgs, lib, ... }:
+
+{
+  ############################################
+  # Base system
+  ############################################
+  nixpkgs.hostPlatform = "x86_64-linux";
+  system.stateVersion = "24.11";
+
+  # Simple console-based kiosk using cage (Wayland single-app compositor)
+  services.xserver.enable = false; # Not using an X11 display manager
+
+  # Autologin to TTY1 as kiosk user
+  services.getty.autologinUser = "kiosk";
+
+  # Kiosk user
+  users.users.kiosk = {
+    isNormalUser = true;
+    description = "Kiosk User";
+    home = "/home/kiosk";
+    extraGroups = [ "wheel" ];
+    initialPassword = "kiosk";
+  };
+
+  # Packages required (aligning with the Debian preseed intent)
+  environment.systemPackages = with pkgs; [
+    firefox
+    cage
+    curl
+    unzip
+    # chromium # available if you want it in addition to Firefox
+  ];
+
+  ############################################
+  # Firefox policies (preconfigured profile settings)
+  ############################################
+  programs.firefox = {
+    enable = true;
+    policies = {
+      DisableDeveloperTools = true;
+      BlockAboutAddons = true;
+      BlockAboutConfig = true;
+      BlockAboutProfiles = true;
+      BlockAboutSupport = true;
+      DisableFirefoxAccounts = true;
+      DisablePrivateBrowsing = true;
+      DisableProfileImport = true;
+      DisableProfileRefresh = true;
+      DisableSafeMode = true;
+      DisablePocket = true;
+      DisableFirefoxScreenshots = true;
+      DisableSetDesktopBackground = true;
+
+      Homepage = {
+        URL = "https://mahn.ke";
+        Locked = true;
+      };
+
+      NewTabPage = { Enabled = false; };
+
+      # Use a Linux path for downloads in kiosk
+      DownloadDirectory = {
+        Path = "/home/kiosk/Downloads";
+        Locked = true;
+      };
+
+      PromptForDownloadLocation = false;
+      StartDownloadsInTempDirectory = false;
+      DisableAppUpdate = true;
+
+      Permissions = {
+        Camera = "deny";
+        Microphone = "deny";
+        Location = "deny";
+        Notifications = "deny";
+      };
+
+      ShowHomeButton = false;
+      DisplayMenuBar = false;
+      DisplayBookmarksToolbar = false;
+
+      # Extension & user messaging controls (per your Debian policy JSON)
+      UserMessaging = {
+        ExtensionRecommendations = false;
+        FeatureRecommendations = false;
+        UrlbarInterventions = false;
+        SkipOnboarding = false;
+        MoreFromMozilla = false;
+        FirefoxLabs = false;
+        Locked = false;
+      };
+
+      # Install Tampermonkey automatically (Firefox will fetch at runtime).
+      # Note: AMO URL may change; this is the typical latest channel.
+      Extensions = {
+        Install = [
+          "https://addons.mozilla.org/firefox/downloads/latest/tampermonkey/latest.xpi"
+        ];
+      };
+    };
+
+    # Helpful preferences to keep Firefox minimal
+    preferences = {
+      "browser.fullscreen.autohide" = true;
+      "browser.shell.checkDefaultBrowser" = false;
+      "browser.startup.page" = 1; # Start with homepage
+    };
+  };
+
+  ############################################
+  # Kiosk launch behavior (replicates your bash_profile approach)
+  ############################################
+  # Create a bash_profile for the kiosk user that launches cage + firefox
+  system.activationScripts.kioskBashProfile = lib.stringAfter ["users"] ''
+    mkdir -p /home/kiosk
+    chown kiosk:kiosk /home/kiosk
+    sudo -u kiosk mkdir -p /home/kiosk/.config
+    cat > /home/kiosk/.bash_profile <<'EOF'
+if [ -z "$WAYLAND_DISPLAY" ] && [ "$(tty)" = "/dev/tty1" ]; then
+    exec ${pkgs.cage}/bin/cage ${pkgs.firefox}/bin/firefox --kiosk https://c3nav.de
+fi
+EOF
+    chown kiosk:kiosk /home/kiosk/.bash_profile
+  '';
+
+  ############################################
+  # Include your userscripts in the image for easy import
+  ############################################
+  environment.etc."kiosk/tampermonkey".source = ./../tampermonkey;
+
+  ############################################
+  # Networking & basic services
+  ############################################
+  networking.hostName = "kiosk";
+  time.timeZone = "UTC";
+  services.openssh.enable = true; # optional, mirrors preseed tasksel ssh-server
+
+  # Keep system simple, disable unneeded DM
+  services.displayManager.enable = false;
+}