let
  krops = builtins.fetchGit { url = "https://cgit.krebsco.de/krops/"; };
  lib = import "${krops}/lib";
  pkgs = import "${krops}/pkgs" { };
  source = machine:
    lib.evalSource [{
      config.file = toString ./machines;
      nixos-config.symlink = "config/${machine}/configuration.nix";
      nixpkgs.git = {
        clean.exclude = [ "/.version-suffix" ];
        ref = "973910f5c31b9ba6c171c33a8bd7199990b14c72"; # nixos-21.05
        url = "https://github.com/NixOS/nixpkgs";
      };
    }];
  mkTestConfig = hostname: {
    name = "test-${hostname}";
    value = pkgs.krops.writeTest "test-${hostname}" {
      source = source hostname;
      target = lib.mkTarget {
        host = "localhost";
        path = "/tmp/src";
      };
      force = true; # force create the sentinel file.
    };
  };
  mkTestsConfig = hostnames: builtins.listToAttrs (map mkTestConfig hostnames);
  mkDeploy = hostname: target: { ${hostname} = pkgs.krops.writeDeploy "deploy-${hostname}" {
    source = source hostname;
    inherit target;
  };
in {}
// mkDeploy "core-services-01" "root@core01.internal.rz.ens.wtf"
// mkDeploy "remote-builder-01" "root@nix01.builders.rz.ens.wtf"
// mkTestsConfig [ "core-services-01" "remote-builder-01" ]