nixos/profiles/hetzner-cloud-cx22: init

It's mostly generic at this point and I want to manage more of them.

configs/nixos/plover/default.nix

@@ -2,16 +2,12 @@
 
 {
   imports = [
-    # Since this will be rarely configured, make sure to import the appropriate
-    # hardware modules depending on the hosting provider (and even just the
-    # server).
-    ./modules/profiles/hetzner-cloud-cx22.nix
-
     # The users for this host.
     (foodogsquaredUtils.getUser "nixos" "admin")
     (foodogsquaredUtils.getUser "nixos" "plover")
 
     "${foodogsquaredModulesPath}/profiles/hardened.nix"
+    "${foodogsquaredModulesPath}/profiles/hetzner-cloud-cx22.nix"
 
     ./disko.nix
 

modules/nixos/profiles/hetzner-cloud-cx22.nix

@@ -0,0 +1,25 @@
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports = [
+    (modulesPath + "/profiles/qemu-guest.nix")
+  ];
+
+  # Hetzner can only support non-UEFI bootloader (or at least it doesn't with
+  # systemd-boot).
+  boot.loader.grub = {
+    enable = lib.mkForce true;
+    efiSupport = true;
+    efiInstallAsRemovable = true;
+  };
+
+  boot.initrd.availableKernelModules = [ "ata_piix" "virtio_pci" "virtio_scsi" "xhci_pci" "sd_mod" "sr_mod" ];
+  boot.initrd.kernelModules = [ "nvme" ];
+
+  zramSwap.enable = true;
+
+  hardware.cpu.intel.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;
+
+  services.qemuGuest.enable = true;
+  systemd.services.qemu-guest-agent.path = [ pkgs.shadow ];
+}