these 2 derivations will be built:
  /nix/store/84zb9l385xknag7afzy2dlfn0v2a1a25-harmonia-deps-3.2.0.drv
  /nix/store/fbddly7gk225src96p2q3mfbamdqd6ic-harmonia-llvm-cov-3.2.0.drv