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Jeff Charles
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Javy: Creating a toolchain for running JavaScript on WebAssembly

Jeff Charles - Shopify

Slides

How to run JavaScript on WebAssembly is not obvious. Javy is an open source toolchain for running JavaScript on WebAssembly that has contributions from developers at multiple companies. Shopify also had to find a way for the WebAssembly modules produced by Javy to be small enough to work efficiently with our infrastructure.

This talk will unpack how Javy uses tools like QuickJS, Wizer, and Binaryen to translate JavaScript input into WebAssembly modules. Additionally, it will cover how we are able to use Wasmtime’s linker, WebAssembly’s multi-memory proposal, and part of the canonical ABI introduced in the component model to enable Javy to create WebAssembly modules that have a size less than 100 KB.

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