Emerging browser runtime target that lets code written in Rust, C++, Python, Ruby, etc. be compiled and executed in the browser. Panel highlights: streaming compilation means code can run almost as soon as the first bytes of a module are loaded; tree-shaking allows loading only the parts of a module actually needed, yielding large performance gains for initial load. Once garbage-collection support and cross-language object hosting inside the JS engine runtime land, isomorphic applications in arbitrary languages become much easier. Case study: Yehuda Katz rewrote Ember's Glimmer rendering engine in Rust, compiled it to WebAssembly, and measured a 0.3–0.5× improvement in LinkedIn initial load time vs the Preact-based rewrite.