feat(niri,xbacklight): Brightness control

hosts/fruitbook/configuration.nix

@@ -11,6 +11,7 @@
     wifi.enable = true;
     stylix.enable = true;
     niri.enable = true;
+    xbacklight-permissions.enable = true;
     users.users = [
       "crumb"
     ];

hosts/fruitbook/disks.nix

@@ -1,73 +0,0 @@
-# sudo nix --experimental-features "nix-command flakes" run github:nix-community/disko/latest -- --mode disko /persist/dots/hosts/nixos-testbed/disko-config.nix
-# time sudo nixos-install --flake /persist/dots#nixos-testbed
-{ lib, ... }:
-{
-  # imports = [ disko.nixosModules.disko ];
-  boot.initrd.supportedFilesystems.btrfs = true;
-  boot.supportedFilesystems.btrfs = true;
-
-  # From Impermanence's README: "Important note: Make sure your persistent
-  # volumes are marked with neededForBoot, otherwise you will run into
-  # problems."
-  fileSystems."/persist".neededForBoot = true;
-
-  disko.devices = {
-    disk = {
-      bootroot = {
-        type = "disk";
-        device = "/dev/disk/by-id/ata-APPLE_SSD_SM0512G_S29ANYAH526520-part4";
-        content = {
-          type = "gpt";
-          partitions = {
-            ESP = {
-              size = "512M";
-              type = "EF00";
-              content = {
-                type = "filesystem";
-                format = "vfat";
-                mountpoint = "/boot";
-                mountOptions = [ "umask=0077" ];
-              };
-            };
-            root = {
-              size = "100%";
-              content = {
-                type = "btrfs";
-
-                mountpoint = "/partition-root";
-                swap.swapfile.size = "4G";
-
-                # Override existing partitions.
-                extraArgs = [ "-f" ];
-
-                # Subvolumes must set a mountpoint in order to be mounted,
-                # *unless their parent is mounted*.
-                subvolumes = {
-                  # Subvolume names do not necessarily correspond to
-                  # mountpoints, despite the structural resemblance to a file
-                  # path.
-                  "/rootfs" = {
-                    mountpoint = "/";
-                  };
-                  "/nix" = {
-                    mountpoint = "/nix";
-                  };
-                  "/persist" = {
-                    mountpoint = "/persist";
-                  };
-                  "/persist/home" = {
-                    mountpoint = "/persist/home";
-                  };
-                  "/swap" = {
-                    mountpoint = "/.swapvol";
-                    swap.swapfile.size = "4G";
-                  };
-                };
-              };
-            };
-          };
-        };
-      };
-    };
-  };
-}

modules/home/users/crumb/niri.nix

@@ -73,7 +73,7 @@ in {
 
         spawn-at-startup =
           [{ command = [ "${pkgs.swaynotificationcenter}/bin/swaync" ]; }
-           { command = [ "${pkgs.gammastep}/bin/gammastep" "-o" "-O" "4000k"
+           { command = [ (lib.getExe pkgs.gammastep) "-o" "-O" "4000k"
                          "-b" "0.9:0.9" "-l" "0:0"]; }]
           ++ lib.optional
             (! builtins.isNull cfg.wallpaper)
@@ -226,8 +226,9 @@ in {
         binds = {
           "Mod+Q".action.close-window = [];
           "Mod+Shift+Q".action.quit = [];
-          "Mod+Ctrl+L".action.spawn = ["${pkgs.swaylock}/bin/swaylock"];
-          "Mod+D".action.spawn = ["${pkgs.fuzzel}/bin/fuzzel"];
+          "Mod+Ctrl+L".action.spawn = [ (lib.getExe pkgs.swaylock) ];
+          "Mod+D".action.spawn = [ (lib.getExe pkgs.fuzzel) ];
+          "XF86LaunchB".action.spawn = [ (lib.getExe pkgs.fuzzel) ];
           "Mod+Shift+Slash".action.show-hotkey-overlay = [];
 
           # Powers off the monitors.  They will be powered back on upon any
@@ -280,6 +281,11 @@ in {
           "Mod+Shift+K".action.move-window-up = []; 
           "Mod+Shift+L".action.move-column-right = []; 
 
+          "XF86MonBrightnessDown".action.spawn =
+            ["${lib.getExe pkgs.acpilight}" "-dec" "10"];
+          "XF86MonBrightnessUp".action.spawn =
+            ["${lib.getExe pkgs.acpilight}" "-inc" "10"];
+
           "Mod+1".action.focus-workspace = [1];
           "Mod+2".action.focus-workspace = [2];
           "Mod+3".action.focus-workspace = [3];

modules/nixos/xbacklight-permissions.nix

@@ -0,0 +1,35 @@
+{ config, lib, pkgs, ... }:
+
+let cfg = config.sydnix.xbacklight-permissions;
+in {
+  options.sydnix.xbacklight-permissions = {
+    enable =
+      lib.mkEnableOption "the user group that is allowed to use xbacklight";
+    group = lib.mkOption {
+      type = lib.types.str;
+      default = "xbacklight";
+    };
+    paths = lib.mkOption {
+      type = with lib.types; listOf str;
+      default = [
+        "/sys/class/backlight/intel_backlight/brightness"
+      ];
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    users.groups.${cfg.group} = {};
+
+    systemd.tmpfiles.settings."50-xbacklight" =
+      lib.mergeAttrsList
+        (builtins.map
+          (path: {
+            ${path}.z = {
+              inherit (cfg) group;
+              mode = "0664";
+              user = "root";
+            };
+          })
+          cfg.paths);
+  };
+}

users/crumb/default.nix

@@ -3,7 +3,13 @@
     isNormalUser = true;
     # TODO: Don't hard-code `persist`.  Use
     # config.sydnix.impermanence.persistGroupName.
-    extraGroups = [ "wheel" "persist" "input" "networkmanager" ];
+    extraGroups = [
+      "wheel"
+      "persist"
+      "input"
+      "networkmanager"
+      "xbacklight"
+    ];
     initialHashedPassword =
       "$y$j9T$aEFDDwdTZbAc6VQRXrkBJ0$K8wxTGTWDihyX1wxJ.ZMH//wmQFfrGGUkLkxIU0Lyq8";