these 2 derivations will be built:
  /nix/store/rmf63m63zbinaq7npk1lc0xi5fnkqgvy-harmonia-deps-3.3.0.drv
  /nix/store/rvyywgb4x3sagw6vxnasjk89xjrdk70i-harmonia-llvm-cov-3.3.0.drv