these 9 derivations will be built:
  /nix/store/jj05aj4wk5d7wl2jxax0anvyy414kryr-source.drv
  /nix/store/h521j3im6c0d6kqhd0i2zgsrjvnw41lx-cargo-package-hyper-1.12.0.drv
  /nix/store/hdgi05595qf4qrq9y3a1ic2m5aiz4g19-cargo-package-want-0.3.2.drv
  /nix/store/s6276l88vcmnhb5xj0j4k4gln9d8z0yv-cargo-src-serde_json-1.0.154.drv
  /nix/store/rykm4sp7fk7f7lq3kj4plkq4jq2ck5bz-cargo-package-serde_json-1.0.154.drv
  /nix/store/v81q10a7hkv7vgwkwdg4624vsp9vmx46-vendor-registry.drv
  /nix/store/n2h3mdq0b4y95hbp4jb0p4h2qilygx80-vendor-cargo-deps.drv
  /nix/store/1fxrbrfqlb8qaa8xcygz5shi60i40j0x-flakelet-relay-deps-0.1.0.drv
  /nix/store/3jvjf5fqqvhgg6n7z76g76cygx67jfgp-flakelet-relay-0.1.0.drv