{
  lib,
  config,
  theme,
  my,
  ...
}:

let
  # Minimal Lua value renderer for the generated fragments.
  toLua =
    v:
    if builtins.isString v then
      ''"${v}"''
    else if builtins.isBool v then
      (if v then "true" else "false")
    else if builtins.isInt v || builtins.isFloat v then
      toString v
    else if v == null then
      "nil"
    else if builtins.isList v then
      "{ " + lib.concatMapStringsSep ", " toLua v + " }"
    else if builtins.isAttrs v then
      "{ " + lib.concatStringsSep ", " (lib.mapAttrsToList (k: val: "${k} = ${toLua val}") v) + " }"
    else
      throw "toLua: unsupported value type";

  themeLua = "return " + toLua { inherit (theme) colors bare; };

  monitorsLua =
    "return "
    + toLua (
      map (
        m:
        {
          inherit (m)
            output
            mode
            position
            scale
            ;
        }
        // lib.optionalAttrs (m.vrr != null) { inherit (m) vrr; }
      ) config.hypr.monitors
    );
in
{
  # -------------------------------------------------------------------------
  # Per-host monitor configuration.
  #
  # Hosts declare their displays once, in hosts/<host>/default.nix, via:
  #   home-manager.users.<my.username>.hypr.monitors = [ { ... } ];
  # The list is rendered to ~/.config/hypr/monitors.lua, which the
  # hand-maintained hyprland.lua pulls in with require("monitors").
  # -------------------------------------------------------------------------
  options.hypr.monitors = lib.mkOption {
    description = "Hyprland monitor rules for this host";
    type = lib.types.listOf (
      lib.types.submodule {
        options = {
          output = lib.mkOption {
            type = lib.types.str;
            default = "";
            description = "Output name or desc: match. Empty string matches every output.";
          };
          mode = lib.mkOption {
            type = lib.types.str;
            default = "preferred";
            description = "Resolution@refresh, e.g. \"3840x2160@164.99Hz\" or \"preferred\".";
          };
          position = lib.mkOption {
            type = lib.types.str;
            default = "auto";
          };
          scale = lib.mkOption {
            type = lib.types.either lib.types.number lib.types.str;
            default = "auto";
          };
          vrr = lib.mkOption {
            type = lib.types.nullOr (lib.types.either lib.types.number lib.types.str);
            default = null;
            description = "Optional per-monitor VRR setting (0/1/on-demand).";
          };
        };
      }
    );
    default = [
      {
        output = "";
        mode = "preferred";
        position = "auto";
        scale = "auto";
      }
    ];
  };

  config = {
    # Live, hand-maintained config: symlinked straight to the repo so edits
    # apply on `hyprctl reload` without a rebuild.
    xdg.configFile."hypr/hyprland.lua".source =
      config.lib.file.mkOutOfStoreSymlink "${my.flakeDir}/home/hypr/hyprland.lua";

    # Generated fragments required by the live config.
    xdg.configFile."hypr/theme.lua".text = themeLua;
    xdg.configFile."hypr/monitors.lua".text = monitorsLua;
  };
}