#./guix-daemon.nix

      ./guix-daemon.nix

## See GNU Guix official site, get the official installation script.
## Runt fearlessly on NixOS, and then add this file to your config.
## In June of 2021 the settings below are current.

let
  makeGuixBuilder = name:
  { isSystemUser = true;
    group = "guixbuild";
    extraGroups = [ "guixbuild" "kvm" ];
    description = "Guix Build user ${name}";
  };
in

  users.groups.guixbuild = { name = "guixbuild"; };
  users.users = builtins.listToAttrs (map (x: {name = "guixbuild${toString x}"; value = makeGuixBuilder "guixbuild${toString x}"; }) (lib.range 0 11) );
  systemd.services.guix-daemon = {
    enable = true;
    description = "Build daemon for GNU Guix";
    after = [ "gnu-store.mount" "var-guix.mount" ];
    serviceConfig = {
      ExecStart = "/var/guix/profiles/per-user/root/current-guix/bin/guix-daemon --build-users-group=guixbuild";
      Environment = "GUIX_LOCPATH=/var/guix/profiles/per-user/root/guix-profile/lib/locale";
      RemainAfterExit = "yes";
      StandardOutput = "syslog";
      StandardError = "syslog";
      TasksMax = "8192";

  systemd =
    { mounts =
        [
          { enable = true;
            before = [ "guix-daemon.service" ];
            description = "Read-only /gnu/store for GNU Guix";
            options = "bind,ro";
            wantedBy = [ "guix-daemon.service" ];
            what = "/gnu/store";
            where = "/gnu/store";
          }
        ];
      services.guix-daemon =
        { enable = true;
          description = "Build daemon for GNU Guix";
          after = [ "gnu-store.mount" ];
          serviceConfig =
            { ExecStart = "/var/guix/profiles/per-user/root/current-guix/bin/guix-daemon --build-users-group=guixbuild";
              Environment = "GUIX_LOCPATH=/var/guix/profiles/per-user/root/guix-profile/lib/locale LC_ALL=en_US.utf8";
              RemainAfterExit = "yes";
              StandardOutput = "syslog";
              StandardError = "syslog";
              TasksMax = "8192";
            };
          wantedBy = [ "multi-user.target" ];
        };

    wantedBy = [ "multi-user.target" ];
  };

      #"/gnu" =
      #  { device = "uf/guix";
      #    fsType = "zfs";
      #    options = [ "noatime" ];
      #  };
      #"/gnu/store" =
      #  { device = "/gnu/store";
      #    options = [ "bind" "ro" ];
      #  };
      #"/var/guix" =
      #  {
      #    device = "/gnu/var/guix";
      #    options = [ "bind" ];
      #  };