# vim: ts=2
{
  config,
  lib,
  pkgs,
  nixpkgs,
  templates,
  ...
}: {
  nix = {
    package = pkgs.nixUnstable;

    registry = {
      nixpkgs.flake = nixpkgs;
      n.flake = nixpkgs;
      t.flake = templates;
    };

    gc = {
      automatic = true;
      dates = "weekly";
      options = "--delete-older-than 7d";
    };
    settings = {
      auto-optimise-store = true;
      experimental-features = ["nix-command" "flakes" "ca-derivations"];

      substituters = "https://cache.ngi0.nixos.org/";
      trusted-public-keys = "cache.ngi0.nixos.org-1:KqH5CBLNSyX184S9BKZJo1LxrxJ9ltnY2uAs5c/f1MA=";
      fallback = true; # TODO what does this do?

      keep-failed = true; #keep failed tmp build dirs
      pure-eval = true; # restrict file system and network access to  hash
    };
  };
}