alt Hacker NewsBut there's not really a great reason for the long build times. There are plenty of languages that compile very fast. The Rust borrowchecker isn't the source of the bulk of the slowness. It seems to be a combination of language design (e.g. they didn't design it for fast compile times from the start), and implementation decisions. It does seem like there's room for a Rust-like language with Go-like tooling, standard lib, and a focus on development speed.
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The Rust compiler, while not extremely fast, is not extremely slow either. As an example, my toy compiler is 130K LoC of Rust and compiles in under 7 seconds on a cold build on my M5 Max. An incremental build is nearly instant. So then why is it that so many projects have a minute compile time with far fewer LoC?
The answer: dependencies (My compiler has virtually none, intentionally)
Rust has a very small stdlib, so you are forced to bring in dependency crates, and not just a few. Many programs have 50-100 or more, and they all have dependencies, and so on. Contrast with Go where it has a culture of few dependencies, and those project have few dependencies. Your Rust compiler is doing a lot more work for what appears to be the same program as in other langs, but ultimately is a lot more code (typically).
To make matters worse, cargo does a decent job of parallelizing the builds, but it can only do so a) at the crate level b) only as much as the dependency graph allows.
It remains to be seen whether you can have a useful borrow checker on top of a simpler type system (at least, a type system that's significantly simpler so as to meaningfully reduce compile times). I have my doubts, personally.