diff --git a/lib/make-disk-image.nix b/lib/make-disk-image.nix
index 572a9ef..572daa2 100644
--- a/lib/make-disk-image.nix
+++ b/lib/make-disk-image.nix
@@ -62,6 +62,7 @@ let
   '';
   installer = ''
     ${systemToInstall.config.system.build.nixos-install}/bin/nixos-install --system ${systemToInstall.config.system.build.toplevel} --keep-going --no-channel-copy -v --no-root-password --option binary-caches ""
+    umount -Rv ${systemToInstall.config.disko.rootMountPoint}
   '';
   QEMU_OPTS = lib.concatMapStringsSep " " (disk: "-drive file=${disk.name}.raw,if=virtio,cache=unsafe,werror=report") (lib.attrValues nixosConfig.config.disko.devices.disk);
 in