these 5 derivations will be built:
  /nix/store/2hdz01dyqhz166fxn8v7a43gl55gd921-vendor-registry.drv
  /nix/store/0kpjzh6z2h0k4w3b8lv07bsvwg88s04g-vendor-cargo-deps.drv
  /nix/store/xkpw107qydjv11hh7dvy775vl1qnzc6q-source.drv
  /nix/store/f655dfcw8g9aq3cv4znmijafcpnf9dlg-harmonia-deps-3.1.0.drv
  /nix/store/i12y77f8msbxq5z7zgj8f1lrqnvabwyl-harmonia-llvm-cov-3.1.0.drv