these 4 derivations will be built:
  /nix/store/gkjmzx28qyp0fb5qn8pmrxlm26s5cqq0-crate-icalendar-0.17.12.tar.gz.drv
  /nix/store/y7lbbmvfny3hp4w7kvszwp02a5h7jxvh-icalendar-0.17.12.drv
  /nix/store/zg0rv87cdxhbryc5qrzhqb4agai9xz4b-cargo-vendor-dir.drv
  /nix/store/6wi3im45c8xhny0dss9xvkbm6zcgchcg-citiesapp-frontend.drv