these 2 derivations will be built:
  /nix/store/lmwrf1vlgawr1y0gq3l2i6hvhwjdapd6-iets-0.1.0.drv
  /nix/store/pszb824d5d3a5xnz45i9h8vidpf6pfh7-iets-partest.drv