diff --git a/.gitignore b/.gitignore
index 8cfe0d4..97ab6ac 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,8 +5,6 @@
 /result
 /target
 /out
-/initrd*
-/patos*
 .*.swp
 .*.swo
 .nixos-test-history
diff --git a/flake.nix b/flake.nix
index 146376c..2e4eafa 100644
--- a/flake.nix
+++ b/flake.nix
@@ -21,18 +21,7 @@
       {
         packages = {
           default = self.packages.${system}.image;
-          image = pkgs.writeShellScriptBin "image" ''
-            set -ex
-            echo "make UKI..."
-
-            mkdir -p patos/efi/boot
-            ${patosPkgs.systemd.out}/usr/bin/ukify build \
-            --linux ${patosPkgs.kernel.kernel}/bzImage \
-            --initrd ${patosPkgs.initrd.out}/initrd.xz \
-            --cmdline "console=ttyS0" \
-            -o patos/efi/boot/bootx64.efi
-          '';
-
+          image = pkgs.callPackage ./image { inherit patosPkgs; };
           kernel = pkgs.callPackage ./kernel { };
           glibc = pkgs.callPackage ./glibc { };
           systemd = pkgs.callPackage ./systemd { };
@@ -60,7 +49,6 @@
             nixfmt-rfc-style
             squashfs-tools-ng
             self.packages.${system}.qemu-uefi-tpm
-            self.packages.${system}.mkinitrd
           ];
         };
 
diff --git a/image/default.nix b/image/default.nix
new file mode 100644
index 0000000..b4394c2
--- /dev/null
+++ b/image/default.nix
@@ -0,0 +1,27 @@
+{
+  pkgs,
+  stdenvNoCC,
+  patosPkgs,
+  ...
+}:
+let
+  version = "0.0.1";
+  pname = "patos-image";
+in
+stdenvNoCC.mkDerivation (finalAttrs: {
+  inherit version;
+  inherit pname;
+
+  buildInputs = with pkgs; [
+    erofs-utils
+    dosfstools
+    mtools
+  ];
+
+  systemd = patosPkgs.systemd.out;
+  kernel = patosPkgs.kernel.kernel;
+  initrd = patosPkgs.initrd.out;
+  rootfs = patosPkgs.rootfs.out;
+
+  builder = ./mkimage.sh;
+})
diff --git a/image/mkimage.sh b/image/mkimage.sh
new file mode 100644
index 0000000..c7473d7
--- /dev/null
+++ b/image/mkimage.sh
@@ -0,0 +1,52 @@
+set -ex -o pipefail
+
+mkdir -p $out/repart.d $out/boot
+pushd $out
+
+# Don't seem to work just to create a symlink to rootfs derivation?
+# ln -sf $rootfs rootfs
+mkdir rootfs
+cp -prP $rootfs/* rootfs/
+find rootfs/ -type d -exec chmod 755 {} \;
+
+$systemd/usr/bin/ukify build \
+  --os-release rootfs/etc/os-release \
+  --linux $kernel/bzImage \
+  --initrd $initrd/initrd.xz \
+  --cmdline "console=ttyS0" \
+  -o boot/patos-x64.efi
+
+cp ${systemd}/usr/lib/systemd/boot/efi/systemd-bootx64.efi boot/
+
+cat <<EOF > repart.d/10-esp.conf
+[Partition]
+Type=esp
+Format=vfat
+SizeMinBytes=96M
+SizeMaxBytes=96M
+SplitName=-
+CopyFiles=/boot/patos-x64.efi:/EFI/Linux/patos-x64.efi
+CopyFiles=/boot/systemd-bootx64.efi:/EFI/BOOT/BOOTX64.EFI
+EOF
+
+cat <<EOF > repart.d/10-root.conf
+[Partition]
+Type=root
+Format=erofs
+CopyFiles=/rootfs:/
+Minimize=best
+SplitName=root
+EOF
+
+$systemd/usr/bin/systemd-repart \
+  --no-pager \
+  --empty=create \
+  --size=1G \
+  --definitions=./repart.d \
+  --root=$out \
+  patos-$version.raw
+
+rm -rf rootfs
+rm -rf boot
+
+popd
diff --git a/utils/qemu-uefi-tpm.nix b/utils/qemu-uefi-tpm.nix
index e6a27f9..d05fbb2 100644
--- a/utils/qemu-uefi-tpm.nix
+++ b/utils/qemu-uefi-tpm.nix
@@ -19,7 +19,7 @@ pkgs.writeShellApplication {
       state="/tmp/patos-qemu-$USER"
       rm -rf "$state"
       mkdir -m 700 "$state"
-      truncate -s 1G "$state/disk.raw"
+      qemu-img create -f qcow2 -F raw -b "$(readlink -e "$1")" "$state/disk.qcow2" 2G
 
       swtpm socket -d --tpmstate dir="$state" \
         --ctrl type=unixio,path="$state/swtpm-sock" \
@@ -44,7 +44,6 @@ pkgs.writeShellApplication {
         -device tpm-tis,tpmdev=tpm0 \
         -netdev id=net00,type=user,hostfwd=tcp::2222-:22 \
         -device virtio-net-pci,netdev=net00 \
-        -drive "file=fat:rw:patos/,format=raw" \
-        -drive "format=raw,file=$state/disk.raw"
+        -drive "format=qcow2,file=$state/disk.qcow2"
     '';
 }