{
  inputs',
  lib,
  ...
}: let
  inherit
    (lib)
    flip
    mapAttrs
    ;
in {
  nix.registry =
    flip mapAttrs inputs'
    (
      n: flake: {inherit flake;}
    );
  nix.settings = {
    substituters = [
      "https://cache.nixos.org/"
      # "https://hydra.redalder.org/"
    ];
    trusted-public-keys = [
      "redalder-nix-cache-1:8t4zBJWgVtrfAOJ45iNHEqA/dDFV47Sr1sGa8ME9ru0="
    ];
    experimental-features = ["flakes" "nix-command" "ca-derivations" "recursive-nix" "dynamic-derivations"];
  };
  nixpkgs.config.allowUnfree = true;
}