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  • Seems like an easy win! I'm kind of surprised nobody did this already. I guess someone will need to reimplement this by hand given Rust's AI policy, but this is still great because it demonstrates that it's a really good idea.
  • As an aside, it's just silly to make the repository a bunch of checked-in patches. Git already does revision control. You don't need to do revision control in your revision control.
  • Those are big improvements!
  • Woah nice thought! :) good idea
  • So this is like a cache? Reminded me of https://turborepo.dev for TS, is it a similar concept?
  • Excited to see if there is a path to getting this in the mainline compiler
  • Huh, I kinda thought something like this was already being done, but perhaps it was a bit later stage. Neat!

    A kind of related shower thought I had, could rustc not instantiate generic methods, but write out what it expects to find (std::Vec<String>::push), and a separate build process listens to these, but makes sure already built ones are not built multiple times from the whole build.

    I don’t actually know how much of duplication there usually is, but I had gotten the impression that it would be part of the problem.

    Of course I’m no compiler engineer, and I’m sure there are complications like per crate build profiles, etc.

  • There’s an interesting comment thread (including potential downsides) about this technique in the submission for “How to speed up the Rust compiler in September 2026” from a couple days ago: https://news.ycombinator.com/item?id=49923594

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