{ lib, pkgs, inputs, config, ... }:
{
  environment.variables = {
    NIXPKGS_ALLOW_UNFREE = "1";
  };

  nixpkgs.flake.setNixPath = true;
  nixpkgs.flake.setFlakeRegistry = true;

  nix = {
    package = pkgs.nixVersions.latest;

    settings = {
      experimental-features = [ "nix-command" "flakes" ];

      auto-optimise-store = true;

      keep-outputs = true;
      keep-derivations = true;

      substituters = [
        "https://nix-community.cachix.org"
        "https://nixpkgs-wayland.cachix.org"
        "https://wezterm.cachix.org"
        "https://niri.cachix.org"
        "https://cache.soopy.moe"
      ];
      trusted-public-keys = [
        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
        "nixpkgs-wayland.cachix.org-1:3lwxaILxMRkVhehr5StQprHdEo4IrE8sRho9R9HOLYA="
        "wezterm.cachix.org-1:kAbhjYUC9qvblTE+s7S+kl5XM1zVa4skO+E/1IDWdH0="
        "niri.cachix.org-1:Wv0OmO7PsuocRKzfDoJ3mulSl7Z6oezYhGhR+3W2964="
        "cache.soopy.moe-1:0RZVsQeR+GOh0VQI9rvnHz55nVXkFardDqfm4+afjPo="
      ];
    };
  };

  nix.optimise.automatic = true;
  nix.gc = {
    automatic = true;
    dates = "weekly";
    options = "--delete-older-than 14d";
  };

  programs.command-not-found.enable = false;
  programs.nix-index.enable = true;

  # compat w/ non-nix programs
  programs.nix-ld.enable = true;
  programs.appimage = {
    enable = true;
    binfmt = true;
  };
}