# TODO: Add build user for servers.

        attrsToList

      inherit (builtins) filter;

      inherit (config) isServer isDarwin;

      nix.distributedBuilds = mkIf (config.networking.hostName != "yuzu") true; # No distributed builds for powerful desktop.
      nix.buildMachines = mkIf (config.networking.hostName != "yuzu") (
        inputs.self.nixosConfigurations
        |> attrsToList
        |> filter ({ name, value }: name != config.networking.hostName && value.config.users.users ? build)
        |> map (
          { name, value }:
          {
            hostName = name;
            maxJobs = 25; # This is handled by remote anyway so not sure what difference it makes..
            protocol = "ssh-ng";
            sshUser = "build";
            sshKey = "/root/.ssh/id";
            supportedFeatures = [
              "benchmark"
              "big-parallel"
              "kvm"
              "nixos-test"
            ];
            system = value.config.nixpkgs.hostPlatform.system;
          }
        )
      );

        |> (if config.isDarwin then concatStringsSep ":" else id);

        |> (if isDarwin then concatStringsSep ":" else id);

          optionals config.isDarwin [

          optionals isDarwin [

      nix.extraOptions = mkIf config.isServer ''

      nix.extraOptions = mkIf isServer ''

{
  config.flake.modules.nixos.nix-distributed-builds =
    {
      inputs,
      config,
      lib,
      ...
    }:
    let
      inherit (lib.attrsets) attrsToList;
      inherit (builtins) filter;
    in
    {
      nix.distributedBuilds = true;
      nix.buildMachines = (
        inputs.self.nixosConfigurations
        |> attrsToList
        |> filter ({ name, value }: name != config.networking.hostName && value.config.users.users ? build)
        |> map (
          { name, value }:
          {
            hostName = name;
            maxJobs = 25; # This is handled by remote anyway so not sure what difference it makes..
            protocol = "ssh-ng";
            sshUser = "build";
            sshKey = "/root/.ssh/id";
            supportedFeatures = [
              "benchmark"
              "big-parallel"
              "kvm"
              "nixos-test"
            ];
            system = value.config.nixpkgs.hostPlatform.system;
          }
        )
      );
    };
  config.flake.modules.nixos.nix-distributed-builder =
    { config, lib, ... }:
    let
      inherit (config.flake) keys;
      inherit (lib.lists) singleton;
    in
    {
      users.users.build = {
        description = "Build";
        isNormalUser = true;
        createHome = false;
        openssh.authorizedKeys.keys = keys.all;
        extraGroups = singleton "build";
      };
    };
}

      nix-distributed-builds
      nix-distributed-builder