13 files changed, 567 insertions, 56 deletions

diff --git a/nixos/doc/manual/release-notes/rl-2311.section.md b/nixos/doc/manual/release-notes/rl-2311.section.md
index af5147e0128..18f44320f07 100644
--- a/nixos/doc/manual/release-notes/rl-2311.section.md
+++ b/nixos/doc/manual/release-notes/rl-2311.section.md
@@ -347,4 +347,6 @@ The module update takes care of the new config syntax and the data itself (user
   can automatically format the root device by setting
   `virtualisation.fileSystems."/".autoFormat = true;`.
 
+- `python3.pkgs.flitBuildHook` has been removed. Use `flit-core` and `format = "pyproject"` instead.
+
 - The `electron` packages now places its application files in `$out/libexec/electron` instead of `$out/lib/electron`. Packages using electron-builder will fail to build and need to be adjusted by changing `lib` to `libexec`.
diff --git a/nixos/modules/hardware/cpu/amd-sev.nix b/nixos/modules/hardware/cpu/amd-sev.nix
index 28ee07f005b..08e1de49638 100644
--- a/nixos/modules/hardware/cpu/amd-sev.nix
+++ b/nixos/modules/hardware/cpu/amd-sev.nix
@@ -1,37 +1,43 @@
-{ config, lib, ... }:
+{ config, options, lib, ... }:
 with lib;
 let
-  cfg = config.hardware.cpu.amd.sev;
-  defaultGroup = "sev";
-in
-  with lib; {
-    options.hardware.cpu.amd.sev = {
-      enable = mkEnableOption (lib.mdDoc "access to the AMD SEV device");
-      user = mkOption {
-        description = lib.mdDoc "Owner to assign to the SEV device.";
-        type = types.str;
-        default = "root";
-      };
-      group = mkOption {
-        description = lib.mdDoc "Group to assign to the SEV device.";
-        type = types.str;
-        default = defaultGroup;
-      };
-      mode = mkOption {
-        description = lib.mdDoc "Mode to set for the SEV device.";
-        type = types.str;
-        default = "0660";
-      };
+  cfgSev = config.hardware.cpu.amd.sev;
+  cfgSevGuest = config.hardware.cpu.amd.sevGuest;
+
+  optionsFor = device: group: {
+    enable = mkEnableOption (lib.mdDoc "access to the AMD ${device} device");
+    user = mkOption {
+      description = lib.mdDoc "Owner to assign to the ${device} device.";
+      type = types.str;
+      default = "root";
+    };
+    group = mkOption {
+      description = lib.mdDoc "Group to assign to the ${device} device.";
+      type = types.str;
+      default = group;
     };
+    mode = mkOption {
+      description = lib.mdDoc "Mode to set for the ${device} device.";
+      type = types.str;
+      default = "0660";
+    };
+  };
+in
+with lib; {
+  options.hardware.cpu.amd.sev = optionsFor "SEV" "sev";
+
+  options.hardware.cpu.amd.sevGuest = optionsFor "SEV guest" "sev-guest";
 
-    config = mkIf cfg.enable {
+  config = mkMerge [
+    # /dev/sev
+    (mkIf cfgSev.enable {
       assertions = [
         {
-          assertion = hasAttr cfg.user config.users.users;
+          assertion = hasAttr cfgSev.user config.users.users;
           message = "Given user does not exist";
         }
         {
-          assertion = (cfg.group == defaultGroup) || (hasAttr cfg.group config.users.groups);
+          assertion = (cfgSev.group == options.hardware.cpu.amd.sev.group.default) || (hasAttr cfgSev.group config.users.groups);
           message = "Given group does not exist";
         }
       ];
@@ -40,12 +46,35 @@ in
         options kvm_amd sev=1
       '';
 
-      users.groups = optionalAttrs (cfg.group == defaultGroup) {
-        "${cfg.group}" = {};
+      users.groups = optionalAttrs (cfgSev.group == options.hardware.cpu.amd.sev.group.default) {
+        "${cfgSev.group}" = { };
       };
 
-      services.udev.extraRules = with cfg; ''
+      services.udev.extraRules = with cfgSev; ''
         KERNEL=="sev", OWNER="${user}", GROUP="${group}", MODE="${mode}"
       '';
-    };
-  }
+    })
+
+    # /dev/sev-guest
+    (mkIf cfgSevGuest.enable {
+      assertions = [
+        {
+          assertion = hasAttr cfgSevGuest.user config.users.users;
+          message = "Given user does not exist";
+        }
+        {
+          assertion = (cfgSevGuest.group == options.hardware.cpu.amd.sevGuest.group.default) || (hasAttr cfgSevGuest.group config.users.groups);
+          message = "Given group does not exist";
+        }
+      ];
+
+      users.groups = optionalAttrs (cfgSevGuest.group == options.hardware.cpu.amd.sevGuest.group.default) {
+        "${cfgSevGuest.group}" = { };
+      };
+
+      services.udev.extraRules = with cfgSevGuest; ''
+        KERNEL=="sev-guest", OWNER="${user}", GROUP="${group}", MODE="${mode}"
+      '';
+    })
+  ];
+}
diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 7744bbd76e6..206d5eaf75d 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -499,6 +499,7 @@
   ./services/games/quake3-server.nix
   ./services/games/teeworlds.nix
   ./services/games/terraria.nix
+  ./services/games/xonotic.nix
   ./services/hardware/acpid.nix
   ./services/hardware/actkbd.nix
   ./services/hardware/argonone.nix
diff --git a/nixos/modules/services/games/xonotic.nix b/nixos/modules/services/games/xonotic.nix
new file mode 100644
index 00000000000..c84347ddc98
--- /dev/null
+++ b/nixos/modules/services/games/xonotic.nix
@@ -0,0 +1,198 @@
+{ config
+, pkgs
+, lib
+, ...
+}:
+
+let
+  cfg = config.services.xonotic;
+
+  serverCfg = pkgs.writeText "xonotic-server.cfg" (
+    toString cfg.prependConfig
+      + "\n"
+      + builtins.concatStringsSep "\n" (
+        lib.mapAttrsToList (key: option:
+          let
+            escape = s: lib.escape [ "\"" ] s;
+            quote = s: "\"${s}\"";
+
+            toValue = x: quote (escape (toString x));
+
+            value = (if lib.isList option then
+              builtins.concatStringsSep
+                " "
+                (builtins.map (x: toValue x) option)
+            else
+              toValue option
+            );
+          in
+          "${key} ${value}"
+        ) cfg.settings
+      )
+      + "\n"
+      + toString cfg.appendConfig
+  );
+in
+
+{
+  options.services.xonotic = {
+    enable = lib.mkEnableOption (lib.mdDoc "Xonotic dedicated server");
+
+    package = lib.mkPackageOption pkgs "xonotic-dedicated" {};
+
+    openFirewall = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = lib.mdDoc ''
+        Open the firewall for TCP and UDP on the specified port.
+      '';
+    };
+
+    dataDir = lib.mkOption {
+      type = lib.types.path;
+      readOnly = true;
+      default = "/var/lib/xonotic";
+      description = lib.mdDoc ''
+        Data directory.
+      '';
+    };
+
+    settings = lib.mkOption {
+      description = lib.mdDoc ''
+        Generates the `server.cfg` file. Refer to [upstream's example][0] for
+        details.
+
+        [0]: https://gitlab.com/xonotic/xonotic/-/blob/master/server/server.cfg
+      '';
+      default = {};
+      type = lib.types.submodule {
+        freeformType = with lib.types; let
+          scalars = oneOf [ singleLineStr int float ];
+        in
+        attrsOf (oneOf [ scalars (nonEmptyListOf scalars) ]);
+
+        options.sv_public = lib.mkOption {
+          type = lib.types.int;
+          default = 0;
+          example = [ (-1) 1 ];
+          description = lib.mdDoc ''
+            Controls whether the server will be publicly listed.
+          '';
+        };
+
+        options.hostname = lib.mkOption {
+          type = lib.types.singleLineStr;
+          default = "Xonotic $g_xonoticversion Server";
+          description = lib.mdDoc ''
+            The name that will appear in the server list. `$g_xonoticversion`
+            gets replaced with the current version.
+          '';
+        };
+
+        options.sv_motd = lib.mkOption {
+          type = lib.types.singleLineStr;
+          default = "";
+          description = lib.mdDoc ''
+            Text displayed when players join the server.
+          '';
+        };
+
+        options.sv_termsofservice_url = lib.mkOption {
+          type = lib.types.singleLineStr;
+          default = "";
+          description = lib.mdDoc ''
+            URL for the Terms of Service for playing on your server.
+          '';
+        };
+
+        options.maxplayers = lib.mkOption {
+          type = lib.types.int;
+          default = 16;
+          description = lib.mdDoc ''
+            Number of player slots on the server, including spectators.
+          '';
+        };
+
+        options.net_address = lib.mkOption {
+          type = lib.types.singleLineStr;
+          default = "0.0.0.0";
+          description = lib.mdDoc ''
+            The address Xonotic will listen on.
+          '';
+        };
+
+        options.port = lib.mkOption {
+          type = lib.types.port;
+          default = 26000;
+          description = lib.mdDoc ''
+            The port Xonotic will listen on.
+          '';
+        };
+      };
+    };
+
+    # Still useful even though we're using RFC 42 settings because *some* keys
+    # can be repeated.
+    appendConfig = lib.mkOption {
+      type = with lib.types; nullOr lines;
+      default = null;
+      description = lib.mdDoc ''
+        Literal text to insert at the end of `server.cfg`.
+      '';
+    };
+
+    # Certain changes need to happen at the beginning of the file.
+    prependConfig = lib.mkOption {
+      type = with lib.types; nullOr lines;
+      default = null;
+      description = lib.mdDoc ''
+        Literal text to insert at the start of `server.cfg`.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    systemd.services.xonotic = {
+      description = "Xonotic server";
+      wantedBy = [ "multi-user.target" ];
+
+      environment = {
+        # Required or else it tries to write the lock file into the nix store
+        HOME = cfg.dataDir;
+      };
+
+      serviceConfig = {
+        DynamicUser = true;
+        User = "xonotic";
+        StateDirectory = "xonotic";
+        ExecStart = "${cfg.package}/bin/xonotic-dedicated";
+
+        # Symlink the configuration from the nix store to where Xonotic actually
+        # looks for it
+        ExecStartPre = [
+          "${pkgs.coreutils}/bin/mkdir -p ${cfg.dataDir}/.xonotic/data"
+          ''
+            ${pkgs.coreutils}/bin/ln -sf ${serverCfg} \
+              ${cfg.dataDir}/.xonotic/data/server.cfg
+          ''
+        ];
+
+        # Cargo-culted from search results about writing Xonotic systemd units
+        ExecReload = "${pkgs.util-linux}/bin/kill -HUP $MAINPID";
+
+        Restart = "on-failure";
+        RestartSec = 10;
+        StartLimitBurst = 5;
+      };
+    };
+
+    networking.firewall.allowedTCPPorts = lib.mkIf cfg.openFirewall [
+      cfg.settings.port
+    ];
+    networking.firewall.allowedUDPPorts = lib.mkIf cfg.openFirewall [
+      cfg.settings.port
+    ];
+  };
+
+  meta.maintainers = with lib.maintainers; [ CobaltCause ];
+}
diff --git a/nixos/modules/services/monitoring/prometheus/exporters.nix b/nixos/modules/services/monitoring/prometheus/exporters.nix
index 66aff30b5ed..1d06893bf1d 100644
--- a/nixos/modules/services/monitoring/prometheus/exporters.nix
+++ b/nixos/modules/services/monitoring/prometheus/exporters.nix
@@ -68,6 +68,7 @@ let
     "redis"
     "rspamd"
     "rtl_433"
+    "sabnzbd"
     "scaphandre"
     "script"
     "shelly"
diff --git a/nixos/modules/services/monitoring/prometheus/exporters/sabnzbd.nix b/nixos/modules/services/monitoring/prometheus/exporters/sabnzbd.nix
new file mode 100644
index 00000000000..41127749401
--- /dev/null
+++ b/nixos/modules/services/monitoring/prometheus/exporters/sabnzbd.nix
@@ -0,0 +1,47 @@
+{ config, lib, pkgs, options }:
+
+let
+  inherit (lib) mkOption types;
+  cfg = config.services.prometheus.exporters.sabnzbd;
+in
+{
+  port = 9387;
+
+  extraOpts = {
+    servers = mkOption {
+      description = "List of sabnzbd servers to connect to.";
+      type = types.listOf (types.submodule {
+        options = {
+          baseUrl = mkOption {
+            type = types.str;
+            description = "Base URL of the sabnzbd server.";
+            example = "http://localhost:8080/sabnzbd";
+          };
+          apiKeyFile = mkOption {
+            type = types.str;
+            description = "File containing the API key.";
+            example = "/run/secrets/sabnzbd_apikey";
+          };
+        };
+      });
+    };
+  };
+
+  serviceOpts =
+    let
+      servers = lib.zipAttrs cfg.servers;
+      apiKeys = lib.concatStringsSep "," (builtins.map (file: "$(cat ${file})") servers.apiKeyFile);
+    in
+    {
+      environment = {
+        METRICS_PORT = toString cfg.port;
+        METRICS_ADDR = cfg.listenAddress;
+        SABNZBD_BASEURLS = lib.concatStringsSep "," servers.baseUrl;
+      };
+
+      script = ''
+        export SABNZBD_APIKEYS="${apiKeys}"
+        exec ${lib.getExe pkgs.prometheus-sabnzbd-exporter}
+      '';
+    };
+}
diff --git a/nixos/modules/tasks/network-interfaces-systemd.nix b/nixos/modules/tasks/network-interfaces-systemd.nix
index dfa883a2c33..679567cbb73 100644
--- a/nixos/modules/tasks/network-interfaces-systemd.nix
+++ b/nixos/modules/tasks/network-interfaces-systemd.nix
@@ -173,6 +173,33 @@ let
     }];
   }));
 
+  bridgeNetworks = mkMerge (flip mapAttrsToList cfg.bridges (name: bridge: {
+    netdevs."40-${name}" = {
+      netdevConfig = {
+        Name = name;
+        Kind = "bridge";
+      };
+    };
+    networks = listToAttrs (forEach bridge.interfaces (bi:
+      nameValuePair "40-${bi}" (mkMerge [ (genericNetwork (mkOverride 999)) {
+        DHCP = mkOverride 0 (dhcpStr false);
+        networkConfig.Bridge = name;
+      } ])));
+  }));
+
+  vlanNetworks = mkMerge (flip mapAttrsToList cfg.vlans (name: vlan: {
+    netdevs."40-${name}" = {
+      netdevConfig = {
+        Name = name;
+        Kind = "vlan";
+      };
+      vlanConfig.Id = vlan.id;
+    };
+    networks."40-${vlan.interface}" = (mkMerge [ (genericNetwork (mkOverride 999)) {
+      vlan = [ name ];
+    } ]);
+  }));
+
 in
 
 {
@@ -182,7 +209,15 @@ in
     # Note this is if initrd.network.enable, not if
     # initrd.systemd.network.enable. By setting the latter and not the
     # former, the user retains full control over the configuration.
-    boot.initrd.systemd.network = mkMerge [(genericDhcpNetworks true) interfaceNetworks];
+    boot.initrd.systemd.network = mkMerge [
+      (genericDhcpNetworks true)
+      interfaceNetworks
+      bridgeNetworks
+      vlanNetworks
+    ];
+    boot.initrd.availableKernelModules =
+      optional (cfg.bridges != {}) "bridge" ++
+      optional (cfg.vlans != {}) "8021q";
   })
 
   (mkIf cfg.useNetworkd {
@@ -212,19 +247,7 @@ in
       }
       (genericDhcpNetworks false)
       interfaceNetworks
-      (mkMerge (flip mapAttrsToList cfg.bridges (name: bridge: {
-        netdevs."40-${name}" = {
-          netdevConfig = {
-            Name = name;
-            Kind = "bridge";
-          };
-        };
-        networks = listToAttrs (forEach bridge.interfaces (bi:
-          nameValuePair "40-${bi}" (mkMerge [ (genericNetwork (mkOverride 999)) {
-            DHCP = mkOverride 0 (dhcpStr false);
-            networkConfig.Bridge = name;
-          } ])));
-      })))
+      bridgeNetworks
       (mkMerge (flip mapAttrsToList cfg.bonds (name: bond: {
         netdevs."40-${name}" = {
           netdevConfig = {
@@ -377,18 +400,7 @@ in
           } ]);
         };
       })))
-      (mkMerge (flip mapAttrsToList cfg.vlans (name: vlan: {
-        netdevs."40-${name}" = {
-          netdevConfig = {
-            Name = name;
-            Kind = "vlan";
-          };
-          vlanConfig.Id = vlan.id;
-        };
-        networks."40-${vlan.interface}" = (mkMerge [ (genericNetwork (mkOverride 999)) {
-          vlan = [ name ];
-        } ]);
-      })))
+      vlanNetworks
     ];
 
     # We need to prefill the slaved devices with networking options
diff --git a/nixos/tests/all-tests.nix b/nixos/tests/all-tests.nix
index a9bac3346b9..a3e85c337aa 100644
--- a/nixos/tests/all-tests.nix
+++ b/nixos/tests/all-tests.nix
@@ -109,6 +109,7 @@ in {
   allTerminfo = handleTest ./all-terminfo.nix {};
   alps = handleTest ./alps.nix {};
   amazon-init-shell = handleTest ./amazon-init-shell.nix {};
+  amd-sev = runTest ./amd-sev.nix;
   anbox = runTest ./anbox.nix;
   anuko-time-tracker = handleTest ./anuko-time-tracker.nix {};
   apcupsd = handleTest ./apcupsd.nix {};
@@ -764,6 +765,7 @@ in {
   systemd-cryptenroll = handleTest ./systemd-cryptenroll.nix {};
   systemd-credentials-tpm2 = handleTest ./systemd-credentials-tpm2.nix {};
   systemd-escaping = handleTest ./systemd-escaping.nix {};
+  systemd-initrd-bridge = handleTest ./systemd-initrd-bridge.nix {};
   systemd-initrd-btrfs-raid = handleTest ./systemd-initrd-btrfs-raid.nix {};
   systemd-initrd-luks-fido2 = handleTest ./systemd-initrd-luks-fido2.nix {};
   systemd-initrd-luks-keyfile = handleTest ./systemd-initrd-luks-keyfile.nix {};
@@ -778,6 +780,7 @@ in {
   systemd-initrd-networkd = handleTest ./systemd-initrd-networkd.nix {};
   systemd-initrd-networkd-ssh = handleTest ./systemd-initrd-networkd-ssh.nix {};
   systemd-initrd-networkd-openvpn = handleTest ./initrd-network-openvpn { systemdStage1 = true; };
+  systemd-initrd-vlan = handleTest ./systemd-initrd-vlan.nix {};
   systemd-journal = handleTest ./systemd-journal.nix {};
   systemd-machinectl = handleTest ./systemd-machinectl.nix {};
   systemd-networkd = handleTest ./systemd-networkd.nix {};
diff --git a/nixos/tests/amd-sev.nix b/nixos/tests/amd-sev.nix
new file mode 100644
index 00000000000..bf9a50c10d0
--- /dev/null
+++ b/nixos/tests/amd-sev.nix
@@ -0,0 +1,56 @@
+{ lib, ... }: {
+  name = "amd-sev";
+  meta = {
+    maintainers = with lib.maintainers; [ trundle veehaitch ];
+  };
+
+  nodes.machine = { lib, ... }: {
+    hardware.cpu.amd.sev.enable = true;
+    hardware.cpu.amd.sevGuest.enable = true;
+
+    specialisation.sevCustomUserGroup.configuration = {
+      users.groups.sevtest = { };
+
+      hardware.cpu.amd.sev = {
+        enable = true;
+        group = "root";
+        mode = "0600";
+      };
+      hardware.cpu.amd.sevGuest = {
+        enable = true;
+        group = "sevtest";
+      };
+    };
+  };
+
+  testScript = { nodes, ... }:
+    let
+      specialisations = "${nodes.machine.system.build.toplevel}/specialisation";
+    in
+    ''
+      machine.wait_for_unit("multi-user.target")
+
+      with subtest("Check default settings"):
+        out = machine.succeed("cat /etc/udev/rules.d/99-local.rules")
+        assert 'KERNEL=="sev", OWNER="root", GROUP="sev", MODE="0660"' in out
+        assert 'KERNEL=="sev-guest", OWNER="root", GROUP="sev-guest", MODE="0660"' in out
+
+        out = machine.succeed("cat /etc/group")
+        assert "sev:" in out
+        assert "sev-guest:" in out
+        assert "sevtest:" not in out
+
+      with subtest("Activate configuration with custom user/group"):
+        machine.succeed('${specialisations}/sevCustomUserGroup/bin/switch-to-configuration test')
+
+      with subtest("Check custom user and group"):
+        out = machine.succeed("cat /etc/udev/rules.d/99-local.rules")
+        assert 'KERNEL=="sev", OWNER="root", GROUP="root", MODE="0600"' in out
+        assert 'KERNEL=="sev-guest", OWNER="root", GROUP="sevtest", MODE="0660"' in out
+
+        out = machine.succeed("cat /etc/group")
+        assert "sev:" not in out
+        assert "sev-guest:" not in out
+        assert "sevtest:" in out
+    '';
+}
diff --git a/nixos/tests/prometheus-exporters.nix b/nixos/tests/prometheus-exporters.nix
index 306c5e071e7..7db7fdf13eb 100644
--- a/nixos/tests/prometheus-exporters.nix
+++ b/nixos/tests/prometheus-exporters.nix
@@ -1178,6 +1178,44 @@ let
       '';
     };
 
+    sabnzbd = {
+      exporterConfig = {
+        enable = true;
+        servers = [{
+          baseUrl = "http://localhost:8080";
+          apiKeyFile = "/var/sabnzbd-apikey";
+        }];
+      };
+
+      metricProvider = {
+        services.sabnzbd.enable = true;
+
+        # unrar is required for sabnzbd
+        nixpkgs.config.allowUnfreePredicate = pkg: builtins.elem (pkgs.lib.getName pkg) [ "unrar" ];
+
+        # extract the generated api key before starting
+        systemd.services.sabnzbd-apikey = {
+          requires = [ "sabnzbd.service" ];
+          after = [ "sabnzbd.service" ];
+          requiredBy = [ "prometheus-sabnzbd-exporter.service" ];
+          before = [ "prometheus-sabnzbd-exporter.service" ];
+          script = ''
+            grep -Po '^api_key = \K.+' /var/lib/sabnzbd/sabnzbd.ini > /var/sabnzbd-apikey
+          '';
+        };
+      };
+
+      exporterTest = ''
+        wait_for_unit("sabnzbd.service")
+        wait_for_unit("prometheus-sabnzbd-exporter.service")
+        wait_for_open_port(8080)
+        wait_for_open_port(9387)
+        wait_until_succeeds(
+            "curl -sSf 'localhost:9387/metrics' | grep 'sabnzbd_queue_size{sabnzbd_instance=\"http://localhost:8080\"} 0.0'"
+        )
+      '';
+    };
+
     scaphandre = {
       exporterConfig = {
         enable = true;
diff --git a/nixos/tests/systemd-initrd-bridge.nix b/nixos/tests/systemd-initrd-bridge.nix
new file mode 100644
index 00000000000..f48a46ff2b9
--- /dev/null
+++ b/nixos/tests/systemd-initrd-bridge.nix
@@ -0,0 +1,63 @@
+import ./make-test-python.nix ({ lib, ... }: {
+  name = "systemd-initrd-bridge";
+  meta.maintainers = [ lib.maintainers.majiir ];
+
+  # Tests bridge interface configuration in systemd-initrd.
+  #
+  # The 'a' and 'b' nodes are connected to a 'bridge' node through different
+  # links. The 'bridge' node configures a bridge across them. It waits forever
+  # in initrd (stage 1) with networking enabled. 'a' and 'b' ping 'bridge' to
+  # test connectivity with the bridge interface. Then, 'a' pings 'b' to test
+  # the bridge itself.
+
+  nodes = {
+    bridge = { config, lib, ... }: {
+      boot.initrd.systemd.enable = true;
+      boot.initrd.network.enable = true;
+      boot.initrd.systemd.services.boot-blocker = {
+        before = [ "initrd.target" ];
+        wantedBy = [ "initrd.target" ];
+        script = "sleep infinity";
+        serviceConfig.Type = "oneshot";
+      };
+
+      networking.primaryIPAddress = "192.168.1.${toString config.virtualisation.test.nodeNumber}";
+
+      virtualisation.vlans = [ 1 2 ];
+      networking.bridges.br0.interfaces = [ "eth1" "eth2" ];
+
+      networking.interfaces = {
+        eth1.ipv4.addresses = lib.mkForce [];
+        eth2.ipv4.addresses = lib.mkForce [];
+        br0.ipv4.addresses = [{
+          address = config.networking.primaryIPAddress;
+          prefixLength = 24;
+        }];
+      };
+    };
+
+    a = {
+      virtualisation.vlans = [ 1 ];
+    };
+
+    b = { config, ... }: {
+      virtualisation.vlans = [ 2 ];
+      networking.primaryIPAddress = lib.mkForce "192.168.1.${toString config.virtualisation.test.nodeNumber}";
+      networking.interfaces.eth1.ipv4.addresses = lib.mkForce [{
+        address = config.networking.primaryIPAddress;
+        prefixLength = 24;
+      }];
+    };
+  };
+
+  testScript = ''
+    start_all()
+    a.wait_for_unit("network.target")
+    b.wait_for_unit("network.target")
+
+    a.succeed("ping -n -w 10 -c 1 bridge >&2")
+    b.succeed("ping -n -w 10 -c 1 bridge >&2")
+
+    a.succeed("ping -n -w 10 -c 1 b >&2")
+  '';
+})
diff --git a/nixos/tests/systemd-initrd-vlan.nix b/nixos/tests/systemd-initrd-vlan.nix
new file mode 100644
index 00000000000..5060163a047
--- /dev/null
+++ b/nixos/tests/systemd-initrd-vlan.nix
@@ -0,0 +1,59 @@
+import ./make-test-python.nix ({ lib, ... }: {
+  name = "systemd-initrd-vlan";
+  meta.maintainers = [ lib.maintainers.majiir ];
+
+  # Tests VLAN interface configuration in systemd-initrd.
+  #
+  # Two nodes are configured for a tagged VLAN. (Note that they also still have
+  # their ordinary eth0 and eth1 interfaces, which are not VLAN-tagged.)
+  #
+  # The 'server' node waits forever in initrd (stage 1) with networking
+  # enabled. The 'client' node pings it to test network connectivity.
+
+  nodes = let
+    network = id: {
+      networking = {
+        vlans."eth1.10" = {
+          id = 10;
+          interface = "eth1";
+        };
+        interfaces."eth1.10" = {
+          ipv4.addresses = [{
+            address = "192.168.10.${id}";
+            prefixLength = 24;
+          }];
+        };
+      };
+    };
+  in {
+    # Node that will use initrd networking.
+    server = network "1" // {
+      boot.initrd.systemd.enable = true;
+      boot.initrd.network.enable = true;
+      boot.initrd.systemd.services.boot-blocker = {
+        before = [ "initrd.target" ];
+        wantedBy = [ "initrd.target" ];
+        script = "sleep infinity";
+        serviceConfig.Type = "oneshot";
+      };
+    };
+
+    # Node that will ping the server.
+    client = network "2";
+  };
+
+  testScript = ''
+    start_all()
+    client.wait_for_unit("network.target")
+
+    # Wait for the regular (untagged) interface to be up.
+    def server_is_up(_) -> bool:
+        status, _ = client.execute("ping -n -c 1 server >&2")
+        return status == 0
+    with client.nested("waiting for server to come up"):
+        retry(server_is_up)
+
+    # Try to ping the (tagged) VLAN interface.
+    client.succeed("ping -n -w 10 -c 1 192.168.10.1 >&2")
+  '';
+})
diff --git a/nixos/tests/tinywl.nix b/nixos/tests/tinywl.nix
index 411cdb1f641..9199866b57a 100644
--- a/nixos/tests/tinywl.nix
+++ b/nixos/tests/tinywl.nix
@@ -16,6 +16,8 @@ import ./make-test-python.nix ({ pkgs, lib, ... }:
         systemPackages = with pkgs; [ tinywl foot wayland-utils ];
       };
 
+      hardware.opengl.enable = true;
+
       # Automatically start TinyWL when logging in on tty1:
       programs.bash.loginShellInit = ''
         if [ "$(tty)" = "/dev/tty1" ]; then