[live-usb] Clean up config

Also switched from trying to override the `nixos` user to instead just
installing home-manager _into_ the `nixos` user. It felt a bit like
fighting the tide otherwise.

build-liveusb.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+# Build Live USB ISO from flake configuration
+# Creates an uncompressed ISO suitable for Ventoy and other USB boot tools
+
+set -e
+
+echo "Building Live USB ISO..."
+nix build .#nixosConfigurations.live-usb.config.system.build.isoImage --show-trace
+
+if [ -f "./result/iso/"*.iso ]; then
+    iso_file=$(ls ./result/iso/*.iso)
+    echo "✅ Build complete!"
+    echo "📁 ISO location: $iso_file"
+    echo "💾 Ready for Ventoy or dd to USB"
+else
+    echo "❌ Build failed - no ISO file found"
+    exit 1
+fi

flake.nix

@@ -74,6 +74,22 @@
       ];
     };
 
+    # Live USB ISO configuration
+    nixosConfigurations.live-usb = nixpkgs.lib.nixosSystem rec {
+      system = "x86_64-linux";
+      modules = baseModules ++ [
+        ./machines/live-usb/configuration.nix
+        {
+          home-manager.users.nixos = { ... }: {
+            imports = [ ./home/home.nix ];
+            home.username = nixpkgs.lib.mkForce "nixos";
+            home.homeDirectory = nixpkgs.lib.mkForce "/home/nixos";
+          };
+          home-manager.extraSpecialArgs = { inherit system; };
+        }
+      ];
+    };
+
     homeConfigurations."johno" = inputs.home-manager.lib.homeManagerConfiguration {
       pkgs = inputs.nixpkgs.legacyPackages."x86_64-linux";
       modules = [

machines/live-usb/configuration.nix

@@ -0,0 +1,89 @@
+# Live USB ISO configuration for recovery and installation
+{ pkgs, modulesPath, ... }:
+
+{
+  imports = [
+    # Use minimal installation CD as base
+    (modulesPath + "/installer/cd-dvd/installation-cd-minimal.nix")
+  ];
+
+  # Use roles structure for consistent configuration
+  roles = {
+    audio.enable = true;
+    bluetooth.enable = true;
+    desktop = {
+      enable = true;
+      kde = true;
+      x11 = true;
+      wayland = true;
+      sddm = true;
+    };
+  };
+
+  # Allow unfree packages for broader hardware support
+  nixpkgs.config.allowUnfree = true;
+
+  # Essential packages for system recovery and installation
+  environment.systemPackages = with pkgs; [
+    # Text editors
+    neovim
+    nano
+    
+    # System tools
+    git
+    curl
+    wget
+    htop
+    tree
+    lsof
+    strace
+    
+    # Filesystem tools
+    btrfs-progs
+    e2fsprogs
+    xfsprogs
+    ntfs3g
+    dosfstools
+    
+    # Network tools
+    networkmanager
+    wirelesstools
+    
+    # Hardware tools
+    pciutils
+    usbutils
+    smartmontools
+    
+    # Archive tools
+    unzip
+    p7zip
+    
+    # Development tools (for quick fixes)
+    gcc
+    binutils
+  ];
+
+  # Enable NetworkManager for easy wifi setup
+  networking.networkmanager.enable = true;
+  
+  # Enable SSH daemon for remote access
+  services.openssh = {
+    enable = true;
+    settings = {
+      PermitRootLogin = "yes";
+      PasswordAuthentication = true;
+    };
+  };
+
+  # ISO customization
+  isoImage = {
+    volumeID = "NIXOS-LIVE";
+  };
+
+  # Enable some useful services
+  services.udisks2.enable = true; # For mounting USB drives
+
+  # Hardware support
+  hardware.enableAllFirmware = true;
+  hardware.enableRedistributableFirmware = true;
+}

roles/printing/default.nix

@@ -19,5 +19,12 @@ in
         nssmdns4 = true;
         openFirewall = true;
       };
+
+      hardware.printers.ensurePrinters = [{
+        name = "MFC-L8900CDW_series";
+        deviceUri = "dnssd://Brother%20MFC-L8900CDW%20series._ipp._tcp.local/?uuid=e3248000-80ce-11db-8000-b422006699d8";
+        model = "everywhere";
+      }];
+      hardware.printers.ensureDefaultPrinter = "MFC-L8900CDW_series";
     };
 }