This isn't anywhere near the top issue that I (or anyone else I know of) encounter with build performance in Rust. Dependent library builds are very parallelizable, so they tend to build quickly. Moreover, the build performance that matters in the day-to-day cycle is mostly rebuild performance, and the binary artifacts are cached in this case.
We could spend time adding a global cache of build artifacts, I guess, but all the time we'd spend working on this wouldn't impact my development velocity much at all. Incremental compilation, on the other hand, would.
It takes me more than one hour on a core duo with 8 GB + HDD, while I occasionally see the same crates being compiled and get to do something else.
I could probably buy a new computer, as this one isn't something that one can easily parallelize, but why should I when my C++ builds are actually fast enough?
I am just an opinated Rust dabbler, please take my complaint as contributing feedback about what I see as one possible show stopper for Windows developers to adopt Rust, vs our current .NET + C++ workflow, in terms of productivity.
Thanks for Rust.