Web bundle size optimization / wasm build best practices

[D1plo1d]

According to the readme:

Simple "hello world" at about 65kb, comparable to React

I have not been able to find any documentation on how to achieve such a small bundle size.

My Results

I've written a simple hello world which compiles with trunk build --release, lto = true, and opt-level="z" down to 275 KB:

use dioxus::prelude::*;

fn main() {
    dioxus_web::launch(App);
}

fn App(cx: Scope) -> Element {
    cx.render(rsx! {
        div {
            "Hello world"
        }
    })
}

This is 4 times the size of the 65KB Readme bundle size. My build size also grows quite quickly to 600KB for a small single page app mockup with just a few simple pages, a router and without any IO.

What best practices are the Dioxus devs applying to get a 64KB build size?

[ealmloff]

Building using the nightly compiler, gzip, trunk wasm opt, and a few tricks from min-sized-rust you can get the wasm size of the above app to 143 KB, which is 62 KB GZIPed: https://github.com/Demonthos/tiny-dioxus

It would be great to either link to min-sized-rust, or provide a guide on how to get binary sizes smaller for WASM specifically in the future

[D1plo1d]

I must be doing something wrong or perhaps there's still a further difference between our setups that I'm not aware of - I've cloned tiny-dioxus and built it with trunk build --release but I'm seeing a 205 KB wasm file in my dist directory. It's much better but not yet 143 KB for some reason.

Edit: I wasn't using the nightly compiler, I am now getting 143 KB. For any fellow Trunk newbies who stumble across this in the future you want to be using RUSTUP_TOOLCHAIN="nightly" trunk build --release

Edit 2: Copying the approach in tiny-dioxus to my SPA also brought my wasm down from 600 KB to 430 KB. This starts to feel more manageable at least for this small project. I'm a bit concerned that this might continue to grow linearly if I tried to build something larger - are there any examples of large Dioxus web apps and their bundle sizes?

[ealmloff]

This was documented in DioxusLabs/docsite#132