servers/machines/lebesgue/config/hardware-configuration.nix

{
  config,
  lib,
  pkgs,
  modulesPath,
  ...
}:
{
  imports = [
    (modulesPath + "/profiles/qemu-guest.nix")
  ];

  services.qemuGuest.enable = true;

  boot.initrd.availableKernelModules = [
    "ata_piix"
    "uhci_hcd"
    "virtio_pci"
    "sr_mod"
    "virtio_blk"
  ];
  boot.initrd.kernelModules = [ ];
  boot.kernelModules = [ ];
  boot.extraModulePackages = [ ];
  boot.supportedFilesystems = [ "btrfs" ];

  boot.initrd.postDeviceCommands = lib.mkAfter ''
    mkdir /btrfs_tmp
    mount /dev/disk/by-label/NIXROOT /btrfs_tmp
    if [[ -e /btrfs_tmp/root ]]; then
        mkdir -p /btrfs_tmp/old_roots
        timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/root)" "+%Y-%m-%-d_%H:%M:%S")
        mv /btrfs_tmp/root "/btrfs_tmp/old_roots/$timestamp"
    fi

    delete_subvolume_recursively() {
        IFS=$'\n'
        for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
            delete_subvolume_recursively "/btrfs_tmp/$i"
        done
        btrfs subvolume delete "$1"
    }

    for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do
        delete_subvolume_recursively "$i"
    done

    btrfs subvolume create /btrfs_tmp/root
    umount /btrfs_tmp
  '';

  fileSystems."/" = {
    device = "/dev/disk/by-label/NIXROOT";
    fsType = "btrfs";
    options = [
      "subvol=root"
      "defaults"
      "noatime"
      "compress=zstd:1"
      "discard=async"
      "nodatacow"
    ];
  };

  fileSystems."/nix" = {
    device = "/dev/disk/by-label/NIXROOT";
    fsType = "btrfs";
    neededForBoot = true;
    options = [
      "subvol=nix"
      "defaults"
      "noatime"
      "compress=zstd:3"
      "discard=async"
      "nodatacow"
    ];
  };

  fileSystems."/persist" = {
    device = "/dev/disk/by-label/NIXROOT";
    fsType = "btrfs";
    neededForBoot = true;
    options = [
      "subvol=persist"
      "defaults"
      "noatime"
      "compress=zstd:1"
      "discard=async"
      "nodatacow"
    ];
  };

  fileSystems."/boot" = {
    device = "/dev/disk/by-label/NIXBOOT";
    fsType = "vfat";
    options = [
      "fmask=0077"
      "dmask=0077"
    ];
  };

  swapDevices = [ ];

  networking.useDHCP = lib.mkDefault true;

  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
}