these 2 derivations will be built:
  /nix/store/qk73raay7caf7dvm75ay320pzy7zzk9c-rootfs-ubuntu-26_04.tar.drv
  /nix/store/p7yyfsms1a2giqygch2s71y8cdfbifba-container-test-ubuntu-26-04-example.drv