these 3 derivations will be built:
  /nix/store/jyk4sf7kgvy7s1khlv6rn6sq1pllam4m-nixos-vm.drv
  /nix/store/6qn0yjaixx3kjmbwc9bsxyjbikf03825-nixos-test-driver-wrappers-regression-PSQL-1387.drv
  /nix/store/7y4h7nrhxlnqqb65kjs0d4jzbspwr0g6-vm-test-run-wrappers-regression-PSQL-1387.drv