{ pkgs, config, ... }: let username = config.defaultUser or "henrov"; in { # Install Thunar and related packages system-wide environment.systemPackages = [ pkgs.thunar pkgs.thunar-plugins pkgs.xarchiver ]; # If you want session variables for Thunar, do it via Home Manager home-manager.users.${username} = { home.sessionVariables = { FILE_MANAGER = "thunar"; USERNAME = username; }; }; }