[imtringued]

There's a tooling problem in the compiler with regards to parallelism, but the real problem is that the Rust ecosystem makes use of intense amounts of code generation features, like serdes, which generates a huge amount of invisible code so that you can serialize and deserialize JSON at speeds that may or may not be practically relevant, but whose impact on compile times is guaranteed.

[pjmlp]

The relevant part is without proper way to cache it, so rebuilding everything requires lots of external stuff that every single developer has to manually configure.

However as language nerd, I still think there is a possible way out of it.