{ config, lib, pkgs, ... }:

{
  nix = {
    # nix settings
    settings = {
      # enable flakes, nix-command and eval-cache
      experimental-features = [ "nix-command" "flakes" "eval-cache" ];
      # auto-optimize my nix-store
      auto-optimise-store = true;
      # use all cores
      max-jobs = "auto";  
      # use all available cores per job
      cores = 0;          
      # add trusted substituters (binary caches)
      substituters = [
        "https://cache.nixos.org"
        "https://nix-community.cachix.org"
      ];
      # add keys
      trusted-public-keys = [
        "cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY="
        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
      ];
    };
    
    # enable automatic garbage collection
    gc = {
      automatic = true;
      dates = "weekly";
      options = "--delete-older-than 7d";
    };
  };

  # links /libexec from derivations to /run/current-system/sw
  environment.pathsToLink = [ "/libexec" ];
  # set the default editor to vim
  environment.variables.EDITOR = "vim";

  # enable home-manager globally
  home-manager.useGlobalPkgs = true;
  home-manager.useUserPackages = true;
  home-manager.backupFileExtension = "backup";
}