Project Setup

Rust

First, you’ll need Rust. To install Rust and the cargo build tool, follow the official instructions.

You also need to install the wasm32-unknown-unknown target to compile Rust to Wasm. If you’re using rustup, you just need to run rustup target add wasm32-unknown-unknown.

info

The minimum supported Rust version (MSRV) for Yew is 1.49.0. Older versions can cause unexpected issues accompanied by incomprehensible error messages. You can check your toolchain version using rustup show (under “active toolchain”) or alternatively rustc --version. To update your toolchain, run rustup update.

Wasm Build Tools

Extra tooling is needed to facilitate the interop between WebAssembly and JavaScript. Additionally, depending on the tool you choose, they can help make deployment and packaging much less of a headache by generating all of the JavaScript code necessary to load and run your app’s .wasm binary in a browser.

trunk

A tool practically made for building Yew apps. It can build any wasm-bindgen based app and its design is inspired by rollup.js. With Trunk you don’t need to have Node.js installed or touch any JavaScript code for that matter. It can bundle assets for your app and even ships with a Sass compiler.

All of our examples are built with Trunk.

Getting started with trunk

wasm-pack

A CLI tool developed by the Rust / Wasm Working Group for packaging up WebAssembly. Best used together with the wasm-pack-plugin for Webpack. The primary purpose of wasm-pack is building Wasm libraries for use in JavaScript. Because of this, it can only build libraries and doesn’t provide useful tools like a development server or automatic rebuilds.

Get started with wasm-pack

cargo-web

This was the best preferred tool to use before the creation of wasm-bindgen.

Getting started with cargo web

Comparison