these 2 derivations will be built:
  /nix/store/iyxxsv0gkzkvy7ysy4nc8ad50xgw5cxy-harmonia-deps-3.3.0.drv
  /nix/store/fi4s9pav5alll9ki57jpf4ac1j79kr0n-harmonia-llvm-cov-3.3.0.drv