these 2 derivations will be built:
  /nix/store/ygym7hrflbh4wqn1yh9y6xgf9a1bsjyh-rootfs-ubuntu-26_04.tar.drv
  /nix/store/k0hv6j2ams26vasw8grggh9ipid7rls7-container-test-ubuntu-26-04-user-packages.drv