feat: add host 'nixos-unstable' as a testing VM

flake.nix

@@ -14,5 +14,10 @@
       ];
       specialArgs = { inherit inputs; };
     };
+    nixosConfigurations.nixos-unstable = nixpkgs-unstable.lib.nixosSystem {
+      modules = [
+        ./hosts/nixos-unstable
+      ];
+    };
   };
 }

hosts/nixos-unstable/configuration.nix

@@ -0,0 +1,47 @@
+{ config, lib, pkgs, ... }:
+
+{
+  # Use the systemd-boot EFI boot loader.
+  boot.loader.systemd-boot.enable = true;
+  boot.loader.efi.canTouchEfiVariables = true;
+
+  # Use latest kernel.
+  boot.kernelPackages = pkgs.linuxPackages_latest;
+
+  networking.hostName = "nixos-unstable"; # Define your hostname.
+
+  # Set your time zone.
+  time.timeZone = "Europe/Amsterdam";
+
+  # Select internationalisation properties.
+  # i18n.defaultLocale = "en_US.UTF-8";
+  # console = {
+  #   font = "Lat2-Terminus16";
+  #   keyMap = "us";
+  #   useXkbConfig = true; # use xkb.options in tty.
+  # };
+
+  # Define a user account. Don't forget to set a password with ‘passwd’.
+  users.mutableUsers = false;
+  users.users.root.hashedPassword = "$y$j9T$i4Yx7PqpLH9bPaNb4SVLm/$dv2gVHCHiRZv.Y00rbNx4QeIExunnfHp57WEnh8qLF1";
+  users.users.alice = {
+    isNormalUser = true;
+    hashedPassword = "";
+    extraGroups = [ "wheel" ]; # Enable ‘sudo’ for the user.
+    packages = with pkgs; [
+      tree
+    ];
+  };
+
+  environment.systemPackages = with pkgs; [
+  ];
+
+  # Open ports in the firewall.
+  # networking.firewall.allowedTCPPorts = [ ... ];
+  # networking.firewall.allowedUDPPorts = [ ... ];
+  # Or disable the firewall altogether.
+  # networking.firewall.enable = false;
+
+  system.stateVersion = "25.05"; # Did you read the comment?
+
+}

hosts/nixos-unstable/default.nix

@@ -0,0 +1,7 @@
+{ inputs, pkgs, ...}: {
+  imports = [
+    ./hardware-configuration.nix
+    ./configuration.nix
+    ../../profiles/base
+  ];
+}

hosts/nixos-unstable/hardware-configuration.nix

@@ -0,0 +1,35 @@
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports =
+    [ (modulesPath + "/profiles/qemu-guest.nix")
+    ];
+
+  boot.initrd.availableKernelModules = [ "ahci" "xhci_pci" "virtio_pci" "sr_mod" "virtio_blk" ];
+  boot.initrd.kernelModules = [ ];
+  boot.initrd.systemd.enable = true;
+  boot.kernelModules = [ "kvm-amd" ];
+  boot.extraModulePackages = [ ];
+
+  fileSystems."/" =
+    { device = "/dev/disk/by-uuid/d696e6e0-64f1-4cb5-9ac6-57a3fd4634cc";
+      fsType = "btrfs";
+    };
+
+  fileSystems."/boot" =
+    { device = "/dev/disk/by-uuid/FA31-9186";
+      fsType = "vfat";
+      options = [ "fmask=0022" "dmask=0022" ];
+    };
+
+  swapDevices = [ ];
+
+  # Enables DHCP on each ethernet and wireless interface. In case of scripted networking
+  # (the default) this is the recommended approach. When using systemd-networkd it's
+  # still possible to use this option, but it's recommended to use it in conjunction
+  # with explicit per-interface declarations with `networking.interfaces.<interface>.useDHCP`.
+  networking.useDHCP = lib.mkDefault true;
+  # networking.interfaces.enp1s0.useDHCP = lib.mkDefault true;
+
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
+}