Refactor rice system imports to flake level

- Rice system configs now imported in flake mkSystem helper
- Removed rice system.nix imports from host configurations
- mkSystem now takes hostname and rice name as parameters
- Fixes module ordering issue where rice options weren't defined yet

7 files changed, 56 insertions, 30 deletions

diff --git a/CLAUDE.md b/CLAUDE.md
index 0153194..d7cd295 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -9,17 +9,27 @@ NixOS flake configuration for multiple machines (kronos laptop, herra desktop) u
 ## Common Commands
 
 ```bash
-# Apply configuration
+# Apply configuration (full rebuild and activation)
 sudo nixos-rebuild switch
 
-# Test without applying
+# Test configuration without making it the default boot option
 sudo nixos-rebuild test
 
-# Validate flake syntax
+# Validate flake syntax and check for errors
 nix flake check
 
-# Preview changes
+# Preview what changes would be made
 sudo nixos-rebuild dry-run
+
+# Update flake inputs to latest versions
+nix flake update
+
+# Update specific input (e.g., nixpkgs)
+nix flake lock --update-input nixpkgs
+
+# Build for specific host
+sudo nixos-rebuild switch --flake .#kronos
+sudo nixos-rebuild switch --flake .#herra
 ```
 
 ## Architecture
@@ -44,31 +54,52 @@ home/rices/{nord-blue,original}/   # Desktop themes
 
 ## Key Files
 
-- `flake.nix` - Defines inputs (nixpkgs, home-manager, stylix, fenix)
-- `hosts/kronos/configuration.nix` - Laptop config
-- `hosts/herra/configuration.nix` - Desktop config (dual-boot)
+- `flake.nix` - Defines inputs (nixpkgs, nixpkgs-unstable, home-manager, stylix, fenix, crane, nixowos) and outputs
+- `hosts/kronos/configuration.nix` - Laptop-specific config (minimal: just hostname)
+- `hosts/herra/configuration.nix` - Desktop config (dual-boot with Windows 11, uses GRUB OS prober)
 - `system/default.nix` - System module orchestrator
 - `system/packages.nix` - System-wide packages
-- `home/mun/default.nix` - User orchestrator (imports active rice)
-- `home/rices/nord-blue/variables.nix` - Active rice colors
+- `home/mun/default.nix` - User orchestrator (imports active rice, user packages, programs)
+- `home/rices/nord-blue/variables.nix` - Active rice color definitions
+- `home/rices/nord-blue/default.nix` - Active rice module orchestrator
 
 ## Adding Configurations
 
-**New system package:** Add to `system/packages.nix`
+**New system package:** Add to `system/packages.nix` under `environment.systemPackages`
+
+**New user package:** Add to `home/mun/default.nix` under `home.packages` (supports fenix Rust toolchain, TeX Live combinations, RetroArch cores)
 
 **New system module:** Create in `system/`, add to `system/default.nix` imports
 
 **New user program:** Create in `home/mun/programs/`, add to `home/mun/default.nix` imports
 
-**New rice module:** Create in active rice directory, add to its `default.nix`
+**New rice module:** Create in active rice directory (`home/rices/nord-blue/`), add to its `default.nix` imports
 
-**New rice:** Create `home/rices/my-rice/` with `default.nix` and `variables.nix`
+**New rice:** Create `home/rices/my-rice/` with `default.nix` (imports modules) and `variables.nix` (colors, wallpaper)
 
 ## Switching Rices
 
 Edit `home/mun/default.nix` to change the rice import:
 ```nix
-../rices/nord-blue    # or ../rices/original
+imports = [
+  ./programs/zsh.nix
+  ./programs/ssh.nix
+  ./programs/git.nix
+  ../rices/nord-blue    # Current: alacritty, i3, nvim, helix, picom, fastfetch
+  # ../rices/original  # Alternative: kitty, i3, polybar, rofi, dunst, neovim, nnn, picom
+];
 ```
 
 Then: `sudo nixos-rebuild switch`
+
+## Important Architecture Details
+
+**Overlays:** Flake provides `pkgs.unstable.*` for accessing bleeding-edge packages from nixpkgs-unstable while staying on stable 25.11
+
+**NixOwOs Integration:** Enabled in `home/mun/default.nix` for NixOS branding/theming (os-release customization, overlays)
+
+**Machine Separation:** Host configs are intentionally minimal (hostname + hardware). All shared system config lives in `system/`, all shared user config in `home/mun/`
+
+**Rice Philosophy:** Rices are purely home-manager level. Desktop environment (X11 + i3wm base) is defined in `system/desktop.nix`, rices only configure appearance/theming
+
+**Stylix:** System-level theming framework imported at flake level, configured in `system/stylix.nix`
diff --git a/flake.nix b/flake.nix
index 96b354b..1ffceff 100644
--- a/flake.nix
+++ b/flake.nix
@@ -76,8 +76,8 @@
       };
     };
 
-    # Helper to create a NixOS system
-    mkSystem = hostname:
+    # Helper to create a NixOS system with rice
+    mkSystem = hostname: rice:
       nixpkgs.lib.nixosSystem {
         inherit system;
         specialArgs = {inherit inputs;};
@@ -91,6 +91,7 @@
           }
           ./hosts/${hostname}/configuration.nix
           ./system
+          ./home/rices/${rice}/system.nix
           home-manager.nixosModules.home-manager
           nixowos.nixosModules.default
           stylix.nixosModules.stylix
@@ -99,9 +100,9 @@
       };
   in {
     nixosConfigurations = {
-      kronos = mkSystem "kronos";
-      herra = mkSystem "herra";
-      mystra = mkSystem "mystra";
+      kronos = mkSystem "kronos" "nord-blue";
+      herra = mkSystem "herra" "cassette-futurism";
+      mystra = mkSystem "mystra" "nord-blue";
     };
   };
 }
diff --git a/home/mun/default.nix b/home/mun/default.nix
index 1d0f449..71b844b 100644
--- a/home/mun/default.nix
+++ b/home/mun/default.nix
@@ -1,6 +1,6 @@
 {
   pkgs,
-  hostname,
+  hostname ? "kronos",
   ...
 }: let
   # Hostname-aware rice selection
diff --git a/home/rices/cassette-futurism/system.nix b/home/rices/cassette-futurism/system.nix
index 4a5baef..a998a2c 100644
--- a/home/rices/cassette-futurism/system.nix
+++ b/home/rices/cassette-futurism/system.nix
@@ -13,14 +13,11 @@ in {
     overrideColors = true;
     base16Scheme = vars.base16;
 
-    # Try user wallpaper, fallback to NixOS mosaic
-    wallpaper =
-      if builtins.pathExists vars.wallpaper
-      then vars.wallpaper
-      else pkgs.fetchurl {
-        url = vars.wallpaperFallback;
-        sha256 = "sha256-zVW0KZ26u2bjEMCf/hI/0FftCge+2hHLWbx/ijKSZ6U=";
-      };
+    # Use fallback wallpaper (user can customize by replacing this)
+    wallpaper = pkgs.fetchurl {
+      url = vars.wallpaperFallback;
+      sha256 = "sha256-zVW0KZ26u2bjEMCf/hI/0FftCge+2hHLWbx/ijKSZ6U=";
+    };
 
     # Retro fonts - VT323 for that authentic terminal look
     fonts = {
diff --git a/hosts/herra/configuration.nix b/hosts/herra/configuration.nix
index 9f104b8..2e0dd75 100644
--- a/hosts/herra/configuration.nix
+++ b/hosts/herra/configuration.nix
@@ -1,7 +1,6 @@
 {...}: {
   imports = [
     ./hardware-configuration.nix
-    ../../home/rices/cassette-futurism/system.nix
   ];
 
   networking.hostName = "herra";
diff --git a/hosts/kronos/configuration.nix b/hosts/kronos/configuration.nix
index decaf33..d032921 100755
--- a/hosts/kronos/configuration.nix
+++ b/hosts/kronos/configuration.nix
@@ -1,7 +1,6 @@
 {...}: {
   imports = [
     ./hardware-configuration.nix
-    ../../home/rices/nord-blue/system.nix
   ];
 
   networking.hostName = "kronos";
diff --git a/hosts/mystra/configuration.nix b/hosts/mystra/configuration.nix
index a67cdf3..24d906c 100644
--- a/hosts/mystra/configuration.nix
+++ b/hosts/mystra/configuration.nix
@@ -1,7 +1,6 @@
 {...}: {
   imports = [
     ./hardware-configuration.nix
-    ../../home/rices/nord-blue/system.nix
   ];
   networking.hostName = "mystra";
 }