these 4 derivations will be built:
  /nix/store/vwi57gszjl4d41rs40qbyn5lpxyaznfl-Cargo.toml.drv
  /nix/store/madcv0pv7zcqalj9v8rvr1q6bda3ai7z-source.drv
  /nix/store/ij19xqsjrrqjighy7fdgqq2d93prph63-harmonia-deps-3.2.0.drv
  /nix/store/hgdvkrlwh2fgjmh44z31yd9r67gh0kz0-harmonia-3.2.0.drv