Plenty of projects ship a) reproducible and b) application binaries. serde-derive is a macro that is used in the compilation of projects. The way the developer

Plenty of projects ship a) reproducible and b) application binaries. serde-derive is a macro that is used in the compilation of projects. The way the developers have implemented it, when you build a project _from source_, it pulls and executes a binary blob against your code. The binary in serde-derive is not reproducible (at least, there is no published hash and other users haven't been able to compile the same binary on their computers), and saves a very minor amount of time - serde-derive has to be compiled once per project per compiler version, unless you delete your dependencies.