these 2 derivations will be built:
  /nix/store/icxyjdarac805k70vk2xjkrc3z71vjw6-nixos-test-driver-pgtap.drv
  /nix/store/qlabhv4k5hrsc1hgpzm1a8ba6za4g3ah-vm-test-run-pgtap.drv