these 5 derivations will be built:
  /nix/store/zdcvdprb4dnf0ssilrrw6fb0cqjvy4m3-vendor-registry.drv
  /nix/store/683c41i8zlkc6q6q03g2k0vanbsxbdzw-vendor-cargo-deps.drv
  /nix/store/rxpcn5v25jqyhm7j1pxichyxh9w6zyc2-source.drv
  /nix/store/8s2krv5zj7d1w8nfriqvzamdwa6lrv9i-harmonia-deps-3.3.0.drv
  /nix/store/5557p89qfli2kvmz345rvzirr7y3k57a-harmonia-llvm-cov-3.3.0.drv