How to speed up wasm build times for faster development iteration?

[bluenote10]

I'm new to both wgpu and targeting wasm, so I may simply lack some basic tricks.

I have started with a basic variation of the hello-triangle example and building my project with wasm-pack build --target web. That works fine, but I noticed that my development iteration cycles are quite slow: Re-compiling my wasm target takes roughly half a minute. It looks like wasm-opt is the dominating contribution to the re-build time. In some other wasm projects of mine that don't use wgpu the re-build times are actually pretty fast.

I'm wondering what are the general recommendations for fast development iteration cycles for wgpu + wasm? Is it e.g. possible to turn off wasm-opt, or is there a kind of "fast optimization" profile? If so, will it only impact the wasm size, or is the optimization actually need for runtime performance as well?

[daxpedda]

Personally I don't have any experience with wasm-pack, but in the past it definitely supported turning off wasm-opt.
wasm-opt definitely impacts performance, but it shouldn't be significant for development builds.

Without wasm-opt, development iteration cycles should be pretty short, but I never figured out a way to decrease them further.

[kpreid]

wasm-pack defaults to a release build (optimized by rustc, like cargo build --release) in addition to running wasm-opt.

You can change both of these at once by running wasm-pack build --dev --target web. It will use the cargo dev profile and will not run wasm-opt.

Also, if you want to disable wasm-opt even for releases, you can configure it using your Cargo.toml.