diff --git a/flake.nix b/flake.nix
index 63296c0..3aa61e9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -331,6 +331,34 @@
           diskSize = "auto";
         };
 
+        # BATM3 (OptiPlex 9030 AIO board-swap) installed image, dd-able to
+        # its SATA drive. Unlike the douro/sintra images, this one grows
+        # itself: growPartition expands the root partition to fill whatever
+        # drive it lands on (16GB today) at first boot and autoResize
+        # stretches the ext4 to match — no manual parted/resize2fs step
+        # after flashing, and all the drive's headroom is available to the
+        # nix store from day one (cf. #55). Image-only override: once
+        # grown, subsequent nixos-rebuilds against plain batm3-installed
+        # are unaffected.
+        disk-image-batm3 =
+          let
+            cfg = self.nixosConfigurations.batm3-installed.extendModules {
+              modules = [
+                {
+                  boot.growPartition = true;
+                  fileSystems."/".autoResize = true;
+                }
+              ];
+            };
+          in
+          import (nixpkgs + "/nixos/lib/make-disk-image.nix") {
+            inherit pkgs lib;
+            config = cfg.config;
+            format = "raw";
+            partitionTableType = "efi";
+            diskSize = "auto";
+          };
+
         # USB-bootable Sintra image with DISTINCT partition labels
         # (nixos-usb / ESP-USB) so the stick can be booted on a Sintra whose
         # eMMC already holds a nixos/ESP-labelled install without a by-label