diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 8eb2ebafb7d..8b6264341a4 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -816,6 +816,7 @@
./services/web-servers/varnish/default.nix
./services/web-servers/zope2.nix
./services/x11/extra-layouts.nix
+ ./services/x11/clight.nix
./services/x11/colord.nix
./services/x11/compton.nix
./services/x11/unclutter.nix
diff --git a/nixos/modules/services/x11/clight.nix b/nixos/modules/services/x11/clight.nix
new file mode 100644
index 00000000000..6ec395bb05e
--- /dev/null
+++ b/nixos/modules/services/x11/clight.nix
@@ -0,0 +1,115 @@
+{ config, pkgs, lib, ... }:
+
+with lib;
+
+let
+ cfg = config.services.clight;
+
+ toConf = v:
+ if builtins.isFloat v then toString v
+ else if isInt v then toString v
+ else if isBool v then boolToString v
+ else if isString v then ''"${escape [''"''] v}"''
+ else if isList v then "[ " + concatMapStringsSep ", " toConf v + " ]"
+ else abort "clight.toConf: unexpected type (v = ${v})";
+
+ clightConf = pkgs.writeText "clight.conf"
+ (concatStringsSep "\n" (mapAttrsToList
+ (name: value: "${toString name} = ${toConf value};")
+ (filterAttrs
+ (_: value: value != null)
+ cfg.settings)));
+in {
+ options.services.clight = {
+ enable = mkOption {
+ type = types.bool;
+ default = false;
+ description = ''
+ Whether to enable clight or not.
+ '';
+ };
+
+ temperature = {
+ day = mkOption {
+ type = types.int;
+ default = 5500;
+ description = ''
+ Colour temperature to use during the day, between
+ 1000 and 25000 K.
+ '';
+ };
+ night = mkOption {
+ type = types.int;
+ default = 3700;
+ description = ''
+ Colour temperature to use at night, between
+ 1000 and 25000 K.
+ '';
+ };
+ };
+
+ settings = let
+ validConfigTypes = with types; either int (either str (either bool float));
+ in mkOption {
+ type = with types; attrsOf (nullOr (either validConfigTypes (listOf validConfigTypes)));
+ default = {};
+ example = { captures = 20; gamma_long_transition = true; ac_capture_timeouts = [ 120 300 60 ]; };
+ description = ''
+ Additional configuration to extend clight.conf. See
+ for a
+ sample configuration file.
+ '';
+ };
+ };
+
+ config = mkIf cfg.enable {
+ boot.kernelModules = [ "i2c_dev" ];
+ environment.systemPackages = with pkgs; [ clight clightd ];
+ services.dbus.packages = with pkgs; [ clight clightd ];
+ services.upower.enable = true;
+
+ services.clight.settings = {
+ gamma_temp = with cfg.temperature; mkDefault [ day night ];
+ } // (optionalAttrs (config.location.provider == "manual") {
+ latitude = mkDefault config.location.latitude;
+ longitude = mkDefault config.location.longitude;
+ });
+
+ services.geoclue2.appConfig."clightc" = {
+ isAllowed = true;
+ isSystem = true;
+ };
+
+ systemd.services.clightd = {
+ requires = [ "polkit.service" ];
+ wantedBy = [ "multi-user.target" ];
+
+ description = "Bus service to manage various screen related properties (gamma, dpms, backlight)";
+ serviceConfig = {
+ Type = "dbus";
+ BusName = "org.clightd.clightd";
+ Restart = "on-failure";
+ RestartSec = 5;
+ ExecStart = ''
+ ${pkgs.clightd}/bin/clightd
+ '';
+ };
+ };
+
+ systemd.user.services.clight = {
+ after = [ "upower.service" "clightd.service" ];
+ wants = [ "upower.service" "clightd.service" ];
+ partOf = [ "graphical-session.target" ];
+ wantedBy = [ "graphical-session.target" ];
+
+ description = "C daemon to adjust screen brightness to match ambient brightness, as computed capturing frames from webcam";
+ serviceConfig = {
+ Restart = "on-failure";
+ RestartSec = 5;
+ ExecStart = ''
+ ${pkgs.clight}/bin/clight --conf-file ${clightConf}
+ '';
+ };
+ };
+ };
+}