refactor: make hosts declarative and consolidate shared config

- add my.username / my.gaming.enable / my.ai.local.enable options and
  gate optional app modules on them instead of per-host import lists
- move vendor-neutral hardware.graphics into modules/graphical, leaving
  only NVIDIA-specific drivers and env vars in modules/hardware/nvidia
- derive the primary user everywhere from my.username (users, getty,
  home-manager, tmpfiles)
- de-duplicate Hyprland autostart down to a single system loginShellInit
  using the start-hyprland wrapper
- consolidate all nixpkgs overlays into modules/core/nix.nix and use
  final.stdenv.hostPlatform.system
- make the zsh rebuild helper target $(hostname) instead of hardcoded hades
- add nixpkgs follows for nixos-hardware, pi and comfy-ui (single nixpkgs)
- add .gitignore and a nixfmt flake formatter; format all nix files
- remove empty browser.nix/display-configuration.nix and rename
  local_ai.nix -> local-ai.nix
- document the my.* toggles in the README

.gitignore

@@ -0,0 +1,9 @@
+# Nix build results
+result
+result-*
+
+# home-manager backup files (backupFileExtension = "backup")
+*.backup
+
+# direnv
+.direnv/

README.md

@@ -24,10 +24,22 @@ rebuild switch   # zsh helper: sudo nixos-rebuild switch --flake ~/NixOS-Configs
 ## Adding a new host (e.g. a laptop)
 
 1. Create `hosts/<name>/` with `default.nix`, `hardware-configuration.nix`, and
-   (optionally) `disko.nix`; import the shared modules (`modules/core`,
+   (optionally) `disko.nix`. Shared modules (`modules/core`, `modules/graphical`,
-   `modules/graphical`, `modules/apps`).
+   `modules/apps`) are already pulled in by `commonModules` in `flake.nix` — the
+   host only adds its own hardware/disko config.
 2. Register it in `flake.nix` under `nixosConfigurations`.
-3. Declare host-specific displays in `hosts/<name>/default.nix`:
+3. Turn optional features on per machine via the shared `my.*` options:
+
+```nix
+# hosts/<name>/default.nix
+my = {
+  username = "anish";      # default; change for a different primary user
+  gaming.enable = false;   # Steam, Gamemode, MangoHud
+  ai.local.enable = false; # Ollama, ComfyUI, Open WebUI
+};
+```
+
+4. Declare host-specific displays in `hosts/<name>/default.nix`:
 
 ```nix
 home-manager.users.anish.volt.monitors = [
@@ -44,4 +56,19 @@ home-manager.users.anish.volt.monitors = [
 
 The `volt.monitors` default (any output @ preferred) keeps every machine working
 out of the box; hosts override only what they need. Hosts without an NVIDIA GPU
-simply don't import `modules/hardware/nvidia.nix` — all vendor env vars live there.
+simply don't import `modules/hardware/nvidia.nix` — all vendor env vars live there,
+while the vendor-neutral `hardware.graphics` stack lives in `modules/graphical`.
+
+## Feature toggles (`my.*`)
+
+Optional app modules are always imported (via `modules/apps/default.nix`) but only
+activate when a host sets the corresponding flag, so hosts never need to edit
+import lists:
+
+| Option | Enables |
+| --- | --- |
+| `my.username` | Primary user (users, home-manager, getty autologin) |
+| `my.gaming.enable` | Steam, Gamemode, MangoHud |
+| `my.ai.local.enable` | Ollama (CUDA), ComfyUI, Open WebUI |
+
+Hardware modules remain explicit imports per host (e.g. `modules/hardware/nvidia.nix`).

flake.lock

@@ -51,7 +51,9 @@
     "comfy-ui": {
       "inputs": {
         "flake-parts": "flake-parts",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": [
+          "nixpkgs"
+        ]
       },
       "locked": {
         "lastModified": 1787851822,
@@ -186,7 +188,9 @@
     },
     "nixos-hardware": {
       "inputs": {
-        "nixpkgs": "nixpkgs_2"
+        "nixpkgs": [
+          "nixpkgs"
+        ]
       },
       "locked": {
         "lastModified": 1788044418,
@@ -205,16 +209,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1766902085,
+        "lastModified": 1787962033,
-        "narHash": "sha256-coBu0ONtFzlwwVBzmjacUQwj3G+lybcZ1oeNSQkgC0M=",
+        "narHash": "sha256-u6z9VTZA4Kf3RkHQo9sQI7NI4Ei/uiU9vrMqOiwWP1Y=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "c0b0e0fddf73fd517c3471e546c0df87a42d53f4",
+        "rev": "c5c4a43b0e8056328ec4529f735cabdb8f1942bb",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-unstable",
+        "ref": "nixos-26.05",
         "repo": "nixpkgs",
         "type": "github"
       }
@@ -250,56 +254,13 @@
         "type": "github"
       }
     },
-    "nixpkgs_2": {
-      "locked": {
-        "lastModified": 1767892417,
-        "narHash": "sha256-8bW3q88CEg2u4hSP66Vf4lpbLonHz7hqDNBMcCY7E9U=",
-        "rev": "3497aa5c9457a9d88d71fa93a4a8368816fbeeba",
-        "type": "tarball",
-        "url": "https://releases.nixos.org/nixos/unstable/nixos-26.05pre924538.3497aa5c9457/nixexprs.tar.xz"
-      },
-      "original": {
-        "type": "tarball",
-        "url": "https://channels.nixos.org/nixos-unstable/nixexprs.tar.xz"
-      }
-    },
-    "nixpkgs_3": {
-      "locked": {
-        "lastModified": 1787962033,
-        "narHash": "sha256-u6z9VTZA4Kf3RkHQo9sQI7NI4Ei/uiU9vrMqOiwWP1Y=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "c5c4a43b0e8056328ec4529f735cabdb8f1942bb",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixos-26.05",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs_4": {
-      "locked": {
-        "lastModified": 1773646010,
-        "narHash": "sha256-iYrs97hS7p5u4lQzuNWzuALGIOdkPXvjz7bviiBjUu8=",
-        "owner": "nixos",
-        "repo": "nixpkgs",
-        "rev": "5b2c2d84341b2afb5647081c1386a80d7a8d8605",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nixos",
-        "ref": "nixos-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
     "pi": {
       "inputs": {
         "bun2nix": "bun2nix",
         "jail-nix": "jail-nix",
-        "nixpkgs": "nixpkgs_4",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
         "systems": "systems"
       },
       "locked": {
@@ -324,7 +285,7 @@
         "herdr": "herdr",
         "home-manager": "home-manager",
         "nixos-hardware": "nixos-hardware",
-        "nixpkgs": "nixpkgs_3",
+        "nixpkgs": "nixpkgs",
         "nixpkgs-unstable": "nixpkgs-unstable",
         "pi": "pi"
       }

flake.nix

@@ -4,7 +4,10 @@
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-26.05";
     nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixos-unstable";
-    nixos-hardware.url = "github:NixOS/nixos-hardware/master";
+    nixos-hardware = {
+      url = "github:NixOS/nixos-hardware/master";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
 
     home-manager = {
       url = "github:nix-community/home-manager/release-26.05";
@@ -23,9 +26,9 @@
 
     comfy-ui = {
       url = "github:utensils/comfyui-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
     };
 
-
     herdr = {
       url = "github:herdrdev/herdr";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -33,6 +36,7 @@
 
     pi = {
       url = "github:lukasl-dev/pi.nix";
+      inputs.nixpkgs.follows = "nixpkgs";
     };
   };
 
@@ -46,26 +50,18 @@
         ./modules/graphical
         ./modules/apps
         inputs.home-manager.nixosModules.home-manager
+        (
+          { config, ... }:
           {
-          nixpkgs.overlays = [
-            (final: prev: {
-              unstable = import inputs.nixpkgs-unstable {
-                inherit (final) system;
-                config.allowUnfree = true;
-              };
-            })
-            inputs.antigravity.overlays.default
-            inputs.comfy-ui.overlays.default
-          ];
-
             home-manager = {
               useGlobalPkgs = true;
               useUserPackages = true;
               extraSpecialArgs = { inherit inputs; };
               backupFileExtension = "backup";
-            users.anish = import ./home;
+              users.${config.my.username} = import ./home;
             };
           }
+        )
       ];
     in
     {
@@ -80,6 +76,8 @@
         };
       };
 
+      formatter.${system} = inputs.nixpkgs.legacyPackages.${system}.nixfmt;
+
       devShells.${system}.default =
         let
           pkgs = import inputs.nixpkgs {

home/brave.nix

@@ -48,6 +48,7 @@ in
     ];
   };
   xdg.configFile."brave/policies/managed/policies.json".text = builtins.toJSON bravePolicies;
-    xdg.configFile."BraveSoftware/Brave-Browser/policies/managed/policies.json".text = builtins.toJSON bravePolicies;
+  xdg.configFile."BraveSoftware/Brave-Browser/policies/managed/policies.json".text =
+    builtins.toJSON bravePolicies;
   xdg.configFile."chromium/policies/managed/policies.json".text = builtins.toJSON bravePolicies;
 }

home/foot.nix

@@ -1,14 +1,22 @@
 { pkgs, inputs, ... }:
 
 let
-  herdrPkg = if (inputs ? herdr && inputs.herdr ? packages && inputs.herdr.packages ? ${pkgs.stdenv.hostPlatform.system})
+  herdrPkg =
-    then inputs.herdr.packages.${pkgs.stdenv.hostPlatform.system}.default
+    if
-    else (pkgs.herdr or null);
+      (
+        inputs ? herdr
+        && inputs.herdr ? packages
+        && inputs.herdr.packages ? ${pkgs.stdenv.hostPlatform.system}
+      )
+    then
+      inputs.herdr.packages.${pkgs.stdenv.hostPlatform.system}.default
+    else
+      (pkgs.herdr or null);
 
   herdrPicker = pkgs.writeShellScriptBin "herdr-picker" (builtins.readFile ./scripts/herdr-picker.sh);
 in
 {
-  home.packages = (if herdrPkg != null then [ herdrPkg ] else []) ++ [
+  home.packages = (if herdrPkg != null then [ herdrPkg ] else [ ]) ++ [
     herdrPicker
   ];
 

home/hypr/default.nix

@@ -1,4 +1,9 @@
-{ pkgs, lib, config, ... }:
+{
+  pkgs,
+  lib,
+  config,
+  ...
+}:
 
 let
   # Deterministic Silicon Volt wallpaper: rendered from SVG at build time,

home/hypr/hyprland.nix

@@ -1,4 +1,9 @@
-{ pkgs, lib, config, ... }:
+{
+  pkgs,
+  lib,
+  config,
+  ...
+}:
 
 let
   mkLua = lib.generators.mkLuaInline;
@@ -8,13 +13,14 @@ in
   # Per-host monitor configuration.
   #
   # Hosts declare their displays once, in hosts/<host>/default.nix, via:
-  #   home-manager.users.anish.volt.monitors = [ { ... } ];
+  #   home-manager.users.<my.username>.volt.monitors = [ { ... } ];
   # and the setting flows into Hyprland here. The default (empty output +
   # preferred mode) works on any machine with any display.
   # -------------------------------------------------------------------------
   options.volt.monitors = lib.mkOption {
     description = "Hyprland monitor rules for this host";
-    type = lib.types.listOf (lib.types.submodule {
+    type = lib.types.listOf (
+      lib.types.submodule {
         options = {
           output = lib.mkOption {
             type = lib.types.str;
@@ -40,15 +46,29 @@ in
             description = "Optional per-monitor VRR setting (0/1/on-demand).";
           };
         };
-    });
+      }
+    );
     default = [
-      { output = ""; mode = "preferred"; position = "auto"; scale = "auto"; }
+      {
+        output = "";
+        mode = "preferred";
+        position = "auto";
+        scale = "auto";
+      }
     ];
   };
 
   config = {
-    wayland.windowManager.hyprland.settings.monitor = map (m:
+    wayland.windowManager.hyprland.settings.monitor = map (
-      { inherit (m) output mode position scale; }
+      m:
+      {
+        inherit (m)
+          output
+          mode
+          position
+          scale
+          ;
+      }
       // (lib.optionalAttrs (m.vrr != null) { inherit (m) vrr; })
     ) config.volt.monitors;
 
@@ -61,9 +81,15 @@ in
         # -----------------------------------------------------------------------
         # 1. Variables & Modifiers (Rendered as Lua local variables)
         # -----------------------------------------------------------------------
-      mainMod = { _var = "SUPER"; };
+        mainMod = {
-      terminal = { _var = "foot"; };
+          _var = "SUPER";
-      browser = { _var = "brave"; };
+        };
+        terminal = {
+          _var = "foot";
+        };
+        browser = {
+          _var = "brave";
+        };
 
         # -----------------------------------------------------------------------
         # 2. Monitors (hl.monitor) - declared per-host via volt.monitors
@@ -74,8 +100,18 @@ in
         # 3. Environment Variables (hl.env)
         # -----------------------------------------------------------------------
         env = [
-        { _args = [ "XCURSOR_SIZE" "24" ]; }
+          {
-        { _args = [ "XDG_SESSION_TYPE" "wayland" ]; }
+            _args = [
+              "XCURSOR_SIZE"
+              "24"
+            ];
+          }
+          {
+            _args = [
+              "XDG_SESSION_TYPE"
+              "wayland"
+            ];
+          }
         ];
 
         # -----------------------------------------------------------------------
@@ -107,7 +143,10 @@ in
             col = {
               # Silicon Volt: electric lime gradient on focus, glass gray at rest
               active_border = {
-              colors = [ "rgba(cffc00ee)" "rgba(e3ff66ee)" ];
+                colors = [
+                  "rgba(cffc00ee)"
+                  "rgba(e3ff66ee)"
+                ];
                 angle = 45;
               };
               inactive_border = "rgba(ffffff14)";
@@ -127,7 +166,10 @@ in
 
             col = {
               border_active = {
-              colors = [ "rgba(cffc00ee)" "rgba(e3ff66ee)" ];
+                colors = [
+                  "rgba(cffc00ee)"
+                  "rgba(e3ff66ee)"
+                ];
                 angle = 45;
               };
               border_inactive = "rgba(ffffff14)";
@@ -184,19 +226,59 @@ in
               "myBezier"
               {
                 type = "bezier";
-              points = [ [ 0.05 0.9 ] [ 0.1 1.05 ] ];
+                points = [
+                  [
+                    0.05
+                    0.9
+                  ]
+                  [
+                    0.1
+                    1.05
+                  ]
+                ];
               }
             ];
           }
         ];
 
         animation = [
-        { leaf = "windows"; enabled = true; speed = 7; bezier = "myBezier"; }
+          {
-        { leaf = "windowsOut"; enabled = true; speed = 7; bezier = "default"; style = "popin 80%"; }
+            leaf = "windows";
-        { leaf = "border"; enabled = true; speed = 10; bezier = "default"; }
+            enabled = true;
-        { leaf = "borderangle"; enabled = true; speed = 8; bezier = "default"; }
+            speed = 7;
-        { leaf = "fade"; enabled = true; speed = 7; bezier = "default"; }
+            bezier = "myBezier";
-        { leaf = "workspaces"; enabled = true; speed = 6; bezier = "default"; }
+          }
+          {
+            leaf = "windowsOut";
+            enabled = true;
+            speed = 7;
+            bezier = "default";
+            style = "popin 80%";
+          }
+          {
+            leaf = "border";
+            enabled = true;
+            speed = 10;
+            bezier = "default";
+          }
+          {
+            leaf = "borderangle";
+            enabled = true;
+            speed = 8;
+            bezier = "default";
+          }
+          {
+            leaf = "fade";
+            enabled = true;
+            speed = 7;
+            bezier = "default";
+          }
+          {
+            leaf = "workspaces";
+            enabled = true;
+            speed = 6;
+            bezier = "default";
+          }
         ];
 
         # -----------------------------------------------------------------------
@@ -206,7 +288,8 @@ in
           {
             _args = [
               "hyprland.start"
-            (mkLua ''function()
+              (mkLua ''
+                function()
                               hl.exec_cmd("qs")
                               hl.exec_cmd("hyprpaper")
                               hl.exec_cmd("mako")
@@ -223,48 +306,178 @@ in
         # -----------------------------------------------------------------------
         bind = [
           # Launchers & Window Controls
-        { _args = [ (mkLua "mainMod .. \" + Q\"") (mkLua "hl.dsp.exec_cmd(terminal)") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + C\"") (mkLua "hl.dsp.window.close()") ]; }
+            _args = [
-        { _args = [ (mkLua "mainMod .. \" + SPACE\"") (mkLua "hl.dsp.exec_cmd(\"rofi -show combi -show-icons\")") ]; }
+              (mkLua "mainMod .. \" + Q\"")
-        { _args = [ (mkLua "mainMod .. \" + N\"") (mkLua "hl.dsp.exec_cmd(\"swaync-client -t -sw\")") ]; }
+              (mkLua "hl.dsp.exec_cmd(terminal)")
-        { _args = [ (mkLua "mainMod .. \" + TAB\"") (mkLua "hl.dsp.exec_cmd(\"qs ipc call overview toggle\")") ]; }
+            ];
-        { _args = [ (mkLua "mainMod .. \" + V\"") (mkLua "hl.dsp.window.float({ action = \"toggle\" })") ]; }
+          }
-        { _args = [ (mkLua "mainMod .. \" + R\"") (mkLua "hl.dsp.exec_cmd(\"rofi -show combi\")") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + G\"") (mkLua "hl.dsp.group.toggle()") ]; }
+            _args = [
-        { _args = [ (mkLua "mainMod .. \" + F\"") (mkLua "hl.dsp.window.fullscreen({ fullscreen = 0 })") ]; }
+              (mkLua "mainMod .. \" + C\"")
+              (mkLua "hl.dsp.window.close()")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + SPACE\"")
+              (mkLua "hl.dsp.exec_cmd(\"rofi -show combi -show-icons\")")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + N\"")
+              (mkLua "hl.dsp.exec_cmd(\"swaync-client -t -sw\")")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + TAB\"")
+              (mkLua "hl.dsp.exec_cmd(\"qs ipc call overview toggle\")")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + V\"")
+              (mkLua "hl.dsp.window.float({ action = \"toggle\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + R\"")
+              (mkLua "hl.dsp.exec_cmd(\"rofi -show combi\")")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + G\"")
+              (mkLua "hl.dsp.group.toggle()")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + F\"")
+              (mkLua "hl.dsp.window.fullscreen({ fullscreen = 0 })")
+            ];
+          }
 
           # Move focus with mainMod + vim
-        { _args = [ (mkLua "mainMod .. \" + h\"") (mkLua "hl.dsp.focus({ direction = \"left\" })") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + l\"") (mkLua "hl.dsp.focus({ direction = \"right\" })") ]; }
+            _args = [
-        { _args = [ (mkLua "mainMod .. \" + k\"") (mkLua "hl.dsp.focus({ direction = \"up\" })") ]; }
+              (mkLua "mainMod .. \" + h\"")
-        { _args = [ (mkLua "mainMod .. \" + j\"") (mkLua "hl.dsp.focus({ direction = \"down\" })") ]; }
+              (mkLua "hl.dsp.focus({ direction = \"left\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + l\"")
+              (mkLua "hl.dsp.focus({ direction = \"right\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + k\"")
+              (mkLua "hl.dsp.focus({ direction = \"up\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + j\"")
+              (mkLua "hl.dsp.focus({ direction = \"down\" })")
+            ];
+          }
 
           # Move focus within a grouped page
-        { _args = [ (mkLua "mainMod .. \" + e\"") (mkLua "hl.dsp.group.next()") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + d\"") (mkLua "hl.dsp.group.prev()") ]; }
+            _args = [
+              (mkLua "mainMod .. \" + e\"")
+              (mkLua "hl.dsp.group.next()")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + d\"")
+              (mkLua "hl.dsp.group.prev()")
+            ];
+          }
 
           # Move window or group with vim keys
-        { _args = [ (mkLua "mainMod .. \" + SHIFT + h\"") (mkLua "hl.dsp.window.move({ direction = \"left\" })") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + SHIFT + l\"") (mkLua "hl.dsp.window.move({ direction = \"right\" })") ]; }
+            _args = [
-        { _args = [ (mkLua "mainMod .. \" + SHIFT + k\"") (mkLua "hl.dsp.window.move({ direction = \"up\" })") ]; }
+              (mkLua "mainMod .. \" + SHIFT + h\"")
-        { _args = [ (mkLua "mainMod .. \" + SHIFT + j\"") (mkLua "hl.dsp.window.move({ direction = \"down\" })") ]; }
+              (mkLua "hl.dsp.window.move({ direction = \"left\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + SHIFT + l\"")
+              (mkLua "hl.dsp.window.move({ direction = \"right\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + SHIFT + k\"")
+              (mkLua "hl.dsp.window.move({ direction = \"up\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + SHIFT + j\"")
+              (mkLua "hl.dsp.window.move({ direction = \"down\" })")
+            ];
+          }
 
           # Scroll through existing workspaces with mainMod + scroll
-        { _args = [ (mkLua "mainMod .. \" + mouse_down\"") (mkLua "hl.dsp.focus({ workspace = \"e+1\" })") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + mouse_up\"") (mkLua "hl.dsp.focus({ workspace = \"e-1\" })") ]; }
+            _args = [
+              (mkLua "mainMod .. \" + mouse_down\"")
+              (mkLua "hl.dsp.focus({ workspace = \"e+1\" })")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + mouse_up\"")
+              (mkLua "hl.dsp.focus({ workspace = \"e-1\" })")
+            ];
+          }
 
           # Lock shortcut
-        { _args = [ (mkLua "mainMod .. \" + S\"") (mkLua "hl.dsp.exec_cmd(\"hyprlock\")") ]; }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + S\"")
+              (mkLua "hl.dsp.exec_cmd(\"hyprlock\")")
+            ];
+          }
 
           # Quick access applications
-        { _args = [ (mkLua "mainMod .. \" + b\"") (mkLua "hl.dsp.exec_cmd(browser)") ]; }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + b\"")
+              (mkLua "hl.dsp.exec_cmd(browser)")
+            ];
+          }
 
           # Scratch workspace
-        { _args = [ (mkLua "mainMod .. \" + RETURN\"") (mkLua "hl.dsp.workspace.toggle_special(\"scratch\")") ]; }
+          {
-        { _args = [ (mkLua "mainMod .. \" + SHIFT + RETURN\"") (mkLua "hl.dsp.window.move({ workspace = \"special:scratch\" })") ]; }
+            _args = [
+              (mkLua "mainMod .. \" + RETURN\"")
+              (mkLua "hl.dsp.workspace.toggle_special(\"scratch\")")
+            ];
+          }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + SHIFT + RETURN\"")
+              (mkLua "hl.dsp.window.move({ workspace = \"special:scratch\" })")
+            ];
+          }
 
           # Messaging workspace
-        { _args = [ (mkLua "mainMod .. \" + M\"") (mkLua "hl.dsp.workspace.toggle_special(\"messaging\")") ]; }
+          {
+            _args = [
+              (mkLua "mainMod .. \" + M\"")
+              (mkLua "hl.dsp.workspace.toggle_special(\"messaging\")")
+            ];
+          }
 
           # Move/resize windows with mouse and dragging
           {
@@ -294,28 +507,40 @@ in
             _args = [
               "XF86AudioLowerVolume"
               (mkLua "hl.dsp.exec_cmd(\"pactl -- set-sink-volume @DEFAULT_SINK@ -5%\")")
-            { repeating = true; locked = true; }
+              {
+                repeating = true;
+                locked = true;
+              }
             ];
           }
           {
             _args = [
               "XF86AudioMute"
               (mkLua "hl.dsp.exec_cmd(\"pactl -- set-sink-mute @DEFAULT_SINK@ toggle\")")
-            { repeating = true; locked = true; }
+              {
+                repeating = true;
+                locked = true;
+              }
             ];
           }
           {
             _args = [
               "XF86MonBrightnessUp"
               (mkLua "hl.dsp.exec_cmd(\"brightnessctl set 5%+\")")
-            { repeating = true; locked = true; }
+              {
+                repeating = true;
+                locked = true;
+              }
             ];
           }
           {
             _args = [
               "XF86MonBrightnessDown"
               (mkLua "hl.dsp.exec_cmd(\"brightnessctl set 5%-\")")
-            { repeating = true; locked = true; }
+              {
+                repeating = true;
+                locked = true;
+              }
             ];
           }
 
@@ -382,17 +607,23 @@ in
         window_rule = [
           {
             name = "signal-messaging";
-          match = { class = "Signal"; };
+            match = {
+              class = "Signal";
+            };
             workspace = "special:messaging";
           }
           {
             name = "vesktop-messaging";
-          match = { class = "vesktop"; };
+            match = {
+              class = "vesktop";
+            };
             workspace = "special:messaging";
           }
           {
             name = "ghidra-tile";
-          match = { class = "ghidra-Ghidra"; };
+            match = {
+              class = "ghidra-Ghidra";
+            };
             float = false;
           }
         ];

home/hypr/quickshell.nix

@@ -1,9 +1,17 @@
 { pkgs, inputs, ... }:
 
 let
-  quickshellPkg = if (inputs ? quickshell && inputs.quickshell ? packages && inputs.quickshell.packages ? ${pkgs.stdenv.hostPlatform.system})
+  quickshellPkg =
-    then inputs.quickshell.packages.${pkgs.stdenv.hostPlatform.system}.default
+    if
-    else (pkgs.quickshell or pkgs.qt6.qtbase);
+      (
+        inputs ? quickshell
+        && inputs.quickshell ? packages
+        && inputs.quickshell.packages ? ${pkgs.stdenv.hostPlatform.system}
+      )
+    then
+      inputs.quickshell.packages.${pkgs.stdenv.hostPlatform.system}.default
+    else
+      (pkgs.quickshell or pkgs.qt6.qtbase);
 in
 {
   home.packages = with pkgs; [

home/nvim/default.nix

@@ -1,4 +1,9 @@
-{ config, pkgs, lib, ... }:
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
 
 let
   treesitterParsers = pkgs.symlinkJoin {
@@ -61,7 +66,9 @@ in
     ];
 
     extraWrapperArgs = [
-            "--set" "NVIM_TREESITTER_PARSERS" "${treesitterParsers}"
+      "--set"
+      "NVIM_TREESITTER_PARSERS"
+      "${treesitterParsers}"
     ];
   };
 

home/rofi.nix

@@ -3,8 +3,7 @@
 let
   # Rofi script-mode indexer: exposes every executable user script
   # (shell, python, whatever) so the launcher finds "everything".
-  rofiScripts = pkgs.writeShellScriptBin "rofi-scripts"
+  rofiScripts = pkgs.writeShellScriptBin "rofi-scripts" (builtins.readFile ./rofi/rofi-scripts.sh);
-    (builtins.readFile ./rofi/rofi-scripts.sh);
 in
 {
   programs.rofi = {

home/zsh/init.zsh

@@ -47,7 +47,7 @@ rebuild () {
     shift 2>/dev/null || true
 
     local config_dir="${FLAKE_CONFIG:-$HOME/NixOS-Configs}"
-    local host="hades"
+    local host="${REBUILD_HOST:-$(hostname)}"
     local target="$config_dir#$host"
 
     case "$action" in

hosts/hades/default.nix

@@ -11,18 +11,21 @@
     inputs.disko.nixosModules.disko
     ./disko.nix
     ./hardware-configuration.nix
-    ./display-configuration.nix
     ../../modules/hardware/nvidia.nix
-    ../../modules/apps/gaming.nix
-    ../../modules/apps/local_ai.nix
   ];
 
   networking.hostName = "hades";
 
+  # Opt this machine into the shared optional feature modules.
+  my = {
+    gaming.enable = true;
+    ai.local.enable = true;
+  };
+
   # ---------------------------------------------------------------------------
   # Host display configuration (absorbed by home/hypr/hyprland.nix)
   # ---------------------------------------------------------------------------
-  home-manager.users.anish.volt.monitors = [
+  home-manager.users.${config.my.username}.volt.monitors = [
     {
       # Samsung Odyssey Ark - matched by description so it survives port changes
       output = "desc:Samsung Electric Company Odyssey Ark H1AK500000";
@@ -44,7 +47,7 @@
 
   # Ensure /games directory is accessible by default user
   systemd.tmpfiles.rules = [
-    "d /games 0755 anish users -"
+    "d /games 0755 ${config.my.username} users -"
   ];
 
   powerManagement.cpuFreqGovernor = "performance";
@@ -58,7 +61,6 @@
   };
 
   environment.systemPackages = with pkgs; [
-    mangohud
     nvtopPackages.nvidia
   ];
 }

hosts/hades/disko.nix

@@ -14,7 +14,10 @@
                 type = "filesystem";
                 format = "vfat";
                 mountpoint = "/boot";
-                mountOptions = [ "fmask=0077" "dmask=0077" ];
+                mountOptions = [
+                  "fmask=0077"
+                  "dmask=0077"
+                ];
               };
             };
             root = {

hosts/hades/display-configuration.nix

@@ -1,5 +0,0 @@
-{ ... }:
-
-{
-  # Host-specific display configurations can be placed here if needed.
-}

hosts/hades/hardware-configuration.nix

@@ -1,14 +1,27 @@
 # Do not modify this file!  It was generated by ‘nixos-generate-config’
 # and may be overwritten by future invocations.  Please make changes
 # to /etc/nixos/configuration.nix instead.
-{ config, lib, pkgs, modulesPath, ... }:
+{
+  config,
+  lib,
+  pkgs,
+  modulesPath,
+  ...
+}:
 
 {
   imports = [
     (modulesPath + "/installer/scan/not-detected.nix")
   ];
 
-  boot.initrd.availableKernelModules = [ "nvme" "xhci_pci" "ahci" "thunderbolt" "usbhid" "sd_mod" ];
+  boot.initrd.availableKernelModules = [
+    "nvme"
+    "xhci_pci"
+    "ahci"
+    "thunderbolt"
+    "usbhid"
+    "sd_mod"
+  ];
   boot.initrd.kernelModules = [ ];
   boot.kernelModules = [ "kvm-amd" ];
   boot.extraModulePackages = [ ];

modules/apps/browser.nix

@@ -1,5 +0,0 @@
-{ ... }:
-
-{
-    # Browser is configured and managed via Home Manager (home/brave.nix)
-}

modules/apps/default.nix

@@ -3,9 +3,10 @@
 {
   imports = [
     ./terminal.nix
-    ./browser.nix
     ./communication.nix
     ./dev.nix
     ./virt.nix
+    ./gaming.nix
+    ./local-ai.nix
   ];
 }

modules/apps/gaming.nix

@@ -1,6 +1,12 @@
-{ pkgs, ... }:
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
 
 {
+  config = lib.mkIf config.my.gaming.enable {
     programs.steam = {
       enable = true;
       remotePlay.openFirewall = false;
@@ -12,4 +18,5 @@
       mangohud
       gamemode
     ];
+  };
 }

modules/apps/local-ai.nix

@@ -0,0 +1,45 @@
+{
+  config,
+  lib,
+  pkgs,
+  inputs,
+  ...
+}:
+
+{
+  imports = [
+    inputs.comfy-ui.nixosModules.default
+  ];
+
+  config = lib.mkIf config.my.ai.local.enable {
+    services = {
+      comfyui = {
+        enable = true;
+        gpuSupport = "cuda";
+        enableManager = true;
+        port = 8188;
+        listenAddress = "0.0.0.0";
+        dataDir = "/var/lib/comfyui";
+        user = "comfyui";
+        group = "comfyui";
+        createUser = true;
+      };
+
+      ollama = {
+        enable = true;
+        package = pkgs.unstable.ollama-cuda;
+        host = "0.0.0.0";
+        port = 11434;
+        user = "ollama";
+        group = "ollama";
+        home = "/var/lib/ollama";
+      };
+
+      open-webui.enable = true;
+    };
+
+    environment.systemPackages = with pkgs; [
+      unstable.ollama-cuda
+    ];
+  };
+}

modules/apps/local_ai.nix

@@ -1,37 +0,0 @@
-{ pkgs, inputs, ... }:
-
-{
-  imports = [
-    inputs.comfy-ui.nixosModules.default
-  ];
-
-  services = {
-    comfyui = {
-      enable = true;
-      gpuSupport = "cuda";
-      enableManager = true;
-      port = 8188;
-      listenAddress = "0.0.0.0";
-      dataDir = "/var/lib/comfyui";
-      user = "comfyui";
-      group = "comfyui";
-      createUser = true;
-    };
-
-    ollama = {
-      enable = true;
-      package = pkgs.unstable.ollama-cuda;
-      host = "0.0.0.0";
-      port = 11434;
-      user = "ollama";
-      group = "ollama";
-      home = "/var/lib/ollama";
-    };
-
-    open-webui.enable = true;
-  };
-
-  environment.systemPackages = with pkgs; [
-    unstable.ollama-cuda
-  ];
-}

modules/apps/virt.nix

@@ -1,4 +1,4 @@
-{ pkgs, ... }:
+{ config, pkgs, ... }:
 
 {
   virtualisation = {
@@ -27,7 +27,7 @@
 
   programs.virt-manager.enable = true;
 
-  users.users.anish.extraGroups = [
+  users.users.${config.my.username}.extraGroups = [
     "libvirtd"
     "kvm"
     "incus-admin"

modules/core/default.nix

@@ -2,6 +2,7 @@
 
 {
   imports = [
+    ../options.nix
     ./system.nix
     ./users.nix
     ./nix.nix

modules/core/nix.nix

@@ -36,12 +36,16 @@
 
   nixpkgs.config.allowUnfree = true;
 
+  # Single source of truth for overlays; the flake module imports only the
+  # modules and does not declare overlays itself.
   nixpkgs.overlays = [
     (final: prev: {
       unstable = import inputs.nixpkgs-unstable {
-        inherit (prev) system;
+        system = final.stdenv.hostPlatform.system;
-        inherit (prev) config;
+        config = final.config;
       };
     })
+    inputs.antigravity.overlays.default
+    inputs.comfy-ui.overlays.default
   ];
 }

modules/core/users.nix

@@ -1,20 +1,20 @@
-{ pkgs, ... }:
+{ config, pkgs, ... }:
 
 {
   users.defaultUserShell = pkgs.zsh;
-    programs.zsh = {
+  programs.zsh.enable = true;
-        enable = true;
-        loginShellInit = ''
-            if [ -z "$DISPLAY" ] && [ "$TTY" = "/dev/tty1" ]; then
-                exec start-hyprland
-            fi
-        '';
-    }; 
 
-    users.users.anish = {
+  users.users.${config.my.username} = {
     isNormalUser = true;
     description = "Main Account";
-        extraGroups = [ "wheel" "networkmanager" "video" "audio" "gaming" "llm" ];
+    extraGroups = [
+      "wheel"
+      "networkmanager"
+      "video"
+      "audio"
+      "gaming"
+      "llm"
+    ];
     openssh.authorizedKeys.keys = [
       # ssh-ed25519 AAAAA.... add my key here to enable ssh from another computer
     ];

modules/graphical/default.nix

@@ -1,4 +1,9 @@
-{ pkgs, lib, ... }:
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
 
 {
   programs.hyprland = {
@@ -6,16 +11,25 @@
     xwayland.enable = true;
   };
 
-    services.getty.autologinUser = "anish";
+  services.getty.autologinUser = config.my.username;
 
   # Boot straight into Hyprland from the first virtual console on any machine.
   # No display manager required; tty2-6 remain available as plain shells.
+  # The start-hyprland wrapper ships with programs.hyprland and sets up the
+  # session environment correctly.
   environment.loginShellInit = ''
     if [ "$(tty)" = "/dev/tty1" ]; then
-            exec ${pkgs.hyprland}/bin/Hyprland
+        exec start-hyprland
     fi
   '';
 
+  # Vendor-neutral graphics stack. Vendor modules (e.g. modules/hardware/nvidia.nix)
+  # only add drivers and vendor-specific environment variables.
+  hardware.graphics = {
+    enable = true;
+    enable32Bit = true;
+  };
+
   # Machine-agnostic Wayland session variables.
   # GPU/vendor specific variables live with their hardware module (e.g. modules/hardware/nvidia.nix).
   environment.sessionVariables = {
@@ -31,11 +45,14 @@
   # Fonts used across the desktop shell (Silicon Volt theme):
   # JetBrains Mono for terminal/UI mono, IBM Plex Sans for UI sans,
   # Instrument Serif for display italics, Nanum Gothic Coding as mono fallback.
-    fonts.packages = with pkgs; [
+  fonts.packages =
+    with pkgs;
+    [
       nerd-fonts.jetbrains-mono
       nerd-fonts.fira-code
       font-awesome
       ibm-plex
       nanum-gothic-coding
-    ] ++ lib.optional (lib.hasAttr "instrument-serif" pkgs) pkgs.instrument-serif;
+    ]
+    ++ lib.optional (lib.hasAttr "instrument-serif" pkgs) pkgs.instrument-serif;
 }

modules/hardware/nvidia.nix

@@ -1,14 +1,19 @@
-{ config, pkgs, lib, ... }:
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
 
 {
-    hardware.graphics = {
-        enable = true;
-        enable32Bit = true;
-    };
-
   services.xserver.videoDrivers = [ "nvidia" ];
 
-    boot.initrd.kernelModules = [ "nvidia" "nvidia_modeset" "nvidia_uvm" "nvidia_drm" ];
+  boot.initrd.kernelModules = [
+    "nvidia"
+    "nvidia_modeset"
+    "nvidia_uvm"
+    "nvidia_drm"
+  ];
   boot.kernelParams = [
     "nvidia-drm.modeset=1"
     "nvidia-drm.fbdev=1"

modules/options.nix

@@ -0,0 +1,20 @@
+{
+  lib,
+  ...
+}:
+
+{
+  # Shared, machine-agnostic configuration surface. Hosts enable optional
+  # feature modules by setting these booleans instead of editing import lists.
+  options.my = {
+    username = lib.mkOption {
+      type = lib.types.str;
+      default = "anish";
+      description = "Primary interactive user account.";
+    };
+
+    gaming.enable = lib.mkEnableOption "Steam, Gamemode and gaming tooling";
+
+    ai.local.enable = lib.mkEnableOption "local AI services (Ollama, ComfyUI, Open WebUI)";
+  };
+}