these 2 derivations will be built:
  /nix/store/q3lkl86wz8wkfj6aqsgps30xnx9cyc6j-hax-0.7.0.drv
  /nix/store/k0jbpjvkb2s2j31rynwhik3c5rm7chw9-check-hax.drv