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Version: 0.19.0

Using wasm-pack

This tool was created by the Rust / Wasm Working Group for building WebAssembly applications. It supports packaging code into npm modules and has an accompanying Webpack plugin for easy integration with existing JavaScript applications. More information is given in the wasm-pack documentation.


wasm-pack requires that you set the crate-type explicitly to include cdylib:

crate-type = ["rlib", "cdylib"]


cargo install wasm-pack


This command will produce a bundle in the ./pkg directory with your app's compiled WebAssembly along with a JavaScript wrapper which can be used to start your application.

wasm-pack build --target web


For more information on rollup.js visit this guide.

rollup ./main.js --format iife --file ./pkg/bundle.js

When using a bundler like rollup.js you can omit --target web.


Feel free to use your preferred server. Here we use a simple Python server to serve the built app.

python -m http.server 8000

If you don't have Python installed, you can install and use the simple-http-server crate instead.