Item — HN Reader

As with most such things, there is considerable nuance to this question. If you're careful with your dependencies and optimizing for compile time, it can be quite good. For example, a clean release build of makepad studio on M1 Max is 8.81s.

There are also patterns that can really bloat compile time, especially heavy use of procedural macros to autogenerate code. Using serde to serialize big, complex data types can be a big compile time hit. Monomorphization can also be a problem, but fortunately careful use of boxing of dyn traits can help a lot with both code size and compile time (miniserde is an alternative to serde that's more optimized on these dimensions).

There's also continual and ongoing work to improve compile times. So overall I would say it's definitely a factor, but not necessarily a showstopper.

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> you're careful with your dependencies and optimizing for compile time, it can be quite good.

The same can be said about c++.

On the other points, every rust project I've seen in the wild makes heavy heavy use of macros, and the majority of projects I've used have a dependency like serde or something. If you're willing to avoid procedural macros and large dependencies, you might as well just work in c++, avoid custom templates and enjoy wicked fast iteration times.

> So overall I would say it's definitely a factor, but not necessarily a showstopper.

I disagree, it is a showstopper for now. It might not be in the future but the situation right now is that comparable c++ and rust projects in my experience have been an order of magnitude in the difference in compile times. My work c++ codebase is a 30 minutes clean build on a 32 core machine with 96GB ram and an NVMe SSD. I can only imagine what an equivalent project would be in my rust if it were as large.

Another real world example, and actually quite relevant to the use case of the original article. Tint and naga are both shader compilers, primarily used for compiling WGSL into SPIR-V, MSL, and HLSL so shaders can be used portably. Tint is in C++ and takes 113.6s for a clean compile on M1 Max. Naga, in Rust, is 17s. That includes serde and a bunch of the usual community crates (quote, syn, thiserror, petgraph).

Admittedly Tint is more mature and sophisticated, but both serve the function I need them for.