{pkgs, ...}: {
  nix.settings = {
    substituters = [
      "https://holochain-ci.cachix.org"
      "https://holochain-ci-internal.cachix.org"
      # "https://cache.holo.host/"
    ];

    trusted-public-keys = [
      "holochain-ci.cachix.org-1:5IUSkZc0aoRS53rfkvH9Kid40NpyjwCMCzwRTXy+QN8="
      "holochain-ci-internal.cachix.org-1:QvVsSrTiearCjrLTVtNtJOdQCDTseXh7UXUuSMx46NE="
      # "cache.holo.host-1:lNXIXtJgS9Iuw4Cu6X0HINLu9sTfcjEntnrgwMQIMcE="
      # "cache.holo.host-2:ZJCkX3AUYZ8soxTLfTb60g+F3MkWD7hkH9y8CgqwhDQ="
    ];
  };
}