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Comment by wrnr | Hacker News Reader

Back in the days the compile times where legendary for being slow and that fact has stuck around but this is no longer true today.

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Rust code is not slow to compile today? I'm currently learning myself some Rust, have a project with some dependencies + ~1500 lines of code in my directory and my debug build with cargo takes 20 seconds every time I change just a line. Specs: Intel i7-7600U (4) @ 2.800GHz, Samsung NVMe SSD SM961/PM961, 16GiB.

Considering the small size of the project, I wouldn't consider that fast and in fact, makes me very turned off on the prospect of the project growing any bigger.

That sounds quite bad to me. It can happen if you have a virus scanner going crazy on your build target during build (which is a common complaint on Windows, you might have to add your Rust projects to an exceptions list). It can also happen if you have really heavy proc macros or other compile-time magic going that needs to reprocess and reexecute often (serde famously can crank up compile times).

I doubt your compile times would really ramp up that much from your project itself getting much bigger. If you are at 1.5k lines of code, the ridiculous compile time is probably due to other causes.

These horrible compile times happen both on Windows and Linux. I am using Serde, but only on two out of 15 structs in total. I haven't really tried to investigate yet if these compile times is just because of my project, but I am using some "standard" crates (like tokio and serde) that the community seems to overall use for most user-facing software, so hopefully they won't "infect" the compile times too much.

Thanks for the pointers though!

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