these 2 derivations will be built:
  /nix/store/zg3mgc20z7l53ji7pgqzhrywq355gbc8-harmonia-deps-3.2.0.drv
  /nix/store/cqcjblh7vj2pgrzk9hz8rmbfrwzf3srl-harmonia-llvm-cov-3.2.0.drv