{ lib, pkgs, ... }: { # The function defining the NixOS module flake.nixosModules.fonts = { config, lib, pkgs, ... }: { # Define an enable option options.mySystem.desktop.fonts.enable = lib.mkEnableOption "Enable nerd-fonts"; # Only apply config if enabled config = lib.mkIf (config.mySystem.desktop.fonts.enable or false) { fonts.packages = with pkgs; [ nerd-fonts.iosevka nerd-fonts.fira-code ]; }; }; }