these 2 derivations will be built:
  /nix/store/8iyswa4sidi2zbq5bhw1psvqyc2m8mpn-harmonia-deps-3.2.0.drv
  /nix/store/g3aw6mba98549mlkkyfj0wdq6zd6v6mx-harmonia-llvm-cov-3.2.0.drv