feat: add wip for 'sd-image-aarch64' image

flake.nix

@@ -76,7 +76,8 @@
       nix.nixPath = [
         "nixpkgs=${inputs.nixpkgs}"
       ]; # <https://github.com/nix-community/nixd/blob/main/nixd/docs/configuration.md>
-      nixosConfigurations = lib.genAttrs hostDirNames (
+      nixosConfigurations =
+        (lib.genAttrs hostDirNames (
           host:
           nixpkgs.lib.nixosSystem {
             modules = [ ./hosts/${host} ];
@@ -84,7 +85,23 @@
               inherit inputs outputs dotsPath;
             };
           }
-      );
+        ))
+        // {
+          sd-image-aarch64 = nixpkgs.lib.nixosSystem {
+            modules = [
+              "${nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
+              ./images/sd-image-aarch64.nix
+              {
+                nixpkgs.config.allowUnsupportedSystem = true;
+                nixpkgs.hostPlatform.system = "aarch64-linux";
+                nixpkgs.buildPlatform.system = "x86_64-linux";
+              }
+            ];
+            specialArgs = {
+              inherit inputs outputs dotsPath;
+            };
+          };
+        };
       homeConfigurations = {
         work = home-manager.lib.homeManagerConfiguration {
           inherit pkgs;
@@ -115,5 +132,7 @@
           inputs
           ;
       };
+
+      images.sd-image-aarch64 = self.nixosConfigurations.sd-image-aarch64.config.system.build.sdImage;
     };
 }

images/sd-image-aarch64.nix

@@ -0,0 +1,9 @@
+# see <https://nixos.wiki/wiki/NixOS_on_ARM#Build_your_own_image_natively>
+
+{
+  imports = [
+    ../modules/ssh/hardened-openssh.nix
+  ];
+
+  ssh.username = "root";
+}