Javascript/TypeScript to WebAssembly AOT compiler: ECMAScript 2026 test262: 70.8% JS host / 60.3% standalone npx js2wasm hello.js --target wasi wasmtime -W gc=y,function-references=y,tail-call=y,exceptions=y hello.wasm js2.loopdive.com #webassembly #wasm #javascript

js2wasm — AOT JavaScript/TypeScript → WebAssembly GC

Direct ahead-of-time compilation to WebAssembly GC with no embedded JS engine — turning every module into a Wasm sandbox for untrusted / AI-generated code.

js2.loopdive.com

Thomas Tränkler@ttraenkler.bsky.social · last mo.

JS² compiles JavaScript to WebAssembly ahead-of-time, sandboxing untrusted modules in your supply chain – running inside JS or standalone, no interpreter/engine. Goal: 100% ECMAScript & NPM compatibility; Method: test-driven, agile agent team against spec + 100.000 unit tests. js2.loopdive.com

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If you have Claude Code installed you're running software that uses the new (unreleased) version of Bun that's been rewritten in Rust - here are two commands you can run to see that for yourself simonwillison.net/2026/Jul/19/...

JS² compiles JavaScript to WebAssembly ahead-of-time, sandboxing untrusted modules in your supply chain – running inside JS or standalone, no interpreter/engine. Goal: 100% ECMAScript & NPM compatibility; Method: test-driven, agile agent team against spec + 100.000 unit tests. js2.loopdive.com

js2wasm — AOT JavaScript/TypeScript → WebAssembly GC

Direct ahead-of-time compilation to WebAssembly GC with no embedded JS engine — turning every module into a Wasm sandbox for untrusted / AI-generated code.

js2.loopdive.com