refactor: automatic options for overlays, fix build

nixosModules/default.nix

@@ -18,6 +18,7 @@
     ./modern-desktop.nix
     ./muede-desktop-settings.nix
     ./nix-ld.nix
+    ./nixpkgs-overlays.nix
     ./openssh.nix
     ./podman.nix
     ./printing.nix

nixosModules/nixpkgs-overlays.nix

@@ -0,0 +1,33 @@
+{
+  lib,
+  config,
+  self,
+  ...
+}:
+{
+  options.my.overlays = {
+    enableAll = lib.mkEnableOption "all nixpkgs overlays";
+  }
+  // lib.mapAttrs (_: _: {
+    enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+    };
+  }) self.overlays;
+
+  config = lib.mkMerge (
+    [
+      {
+        my.overlays = lib.mapAttrs (_: _: {
+          enable = lib.mkDefault config.my.overlays.enableAll;
+        }) self.overlays;
+      }
+    ]
+    ++ lib.mapAttrsToList (
+      name: overlay:
+      lib.mkIf config.my.overlays.${name}.enable {
+        nixpkgs.overlays = [ overlay ];
+      }
+    ) self.overlays
+  );
+}

nixosModules/pxvirt-guest.nix

@@ -1,24 +1,12 @@
 {
-  modulesPath,
   lib,
   config,
   ...
 }:
 {
-  # Import unconditionally — the module only defines options, activating nothing by default.
-  imports = [ (modulesPath + "/virtualisation/proxmox-lxc.nix") ];
-
   options.my.pxvirtGuest.enable = lib.mkEnableOption "Proxmox LXC guest configuration";
 
   config = lib.mkIf config.my.pxvirtGuest.enable {
-    # TODO is this needed?
-    # nix.settings.sandbox = false;
-
-    proxmoxLXC = {
-      manageNetwork = false;
-      privileged = false;
-    };
-
     # Let Proxmox host handle fstrim
     services.fstrim.enable = false;