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Javascript (ECMAScript) AOT compiler. Ship lightweight binaries, not source. Drop the heavy engine and slow interpreter. Sandbox untrusted code.

Munich, Bavaria
Joined August 2026
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JavaScript compiler js2 now passes 99% of the official test suite for the 2015 ECMAScript standard #js #javascript #wasm #webassembly
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Javascript compiler JS² now covers 95% of ECMAScript 2015 unit tests #js #javascript #wasm #webassembly
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A new foundation for our security architecture is needed
An open letter for a global surge in cyber defense, signed by over 100 organizations including Anthropic, AWS, Google, Microsoft, OpenAI, and Oracle.
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First level complete: ECMAScript 5 100% #js #javascript #wasm #webassembly
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First target in sight: 98.5% ECMAScript 5 tests pass. #js #javascript #wasm #webassembly
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2 more options for runtime eval side modules besides the basic interpreter: QuickJS interpreter (fast cold start) JIT compilation (fast on hot loops)
eval support is in – both for strings known at compile time (AOT compiled) and unknown at compile time (optional interpreter side module). passing 96% of eval tests in test262. #javascript #js #webassembly #wasm #ecmascript
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Side modules are only linked when needed - e.g. for eval() of strings unknown at compile time
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Playing „catch me if you can“ with V8’s JIT tier „Turbofan“ on npm packages 🐇 Speed relative to V8: Starting out at less than 10%, already seeing some 2-3 x speedups: 26% on cookie 18% on clsx 16% on acorn js2wasm.loopdive.com #javascript #js #webassembly #wasm
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90% ES5 unlocked: JavaScript to WebAssembly #javascript #js #webassembly #wasm
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If we don’t want to end up in a severe situation we need to tighten up security for what is to come. Code is no longer written or read by humans while AI is finding ways to get in and out without permission. Module sandboxing will be the bare minimum.
I have accepted reality, I no longer write code manually. But man do I miss reading a bug report and knowing exactly off the top of my head the if statement that causes it in the exact file in a 100K+ line codebase.
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eval support is in – both for strings known at compile time (AOT compiled) and unknown at compile time (optional interpreter side module). passing 96% of eval tests in test262. #javascript #js #webassembly #wasm #ecmascript
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This is the new normal. We need better systems to manage AI generated code.
I'm officially done reading AI-generated code. It's been two weeks since I looked at any of it. I think the IDE is officially on its way to the graveyard. The job is no longer about "writing code," so we need new tools that better reflect this new reality. While reviewing the code, I realized my only complaints were stylistic, and I wasn't finding any obvious bugs anymore. The more code I generated, the harder it became to keep track of every line. I found that my time is better spent designing ways to verify that the overall system works than looking at the code. State-of-the-art coding agents are better at writing code than I'd ever be, and I'm going to stop pretending otherwise. I still think these coding agents can't go too far without an experienced human guiding them, but we're past the point where we need to check every line of code.
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Seems like sandboxing needs an upgrade... #js2wasm
AI agents are escaping cybersecurity testing environments and reaching real-world systems, raising questions about whether safety infrastructure, industry standards and regulation can keep pace with increasingly powerful models. spr.ly/6010B1HI8r
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JavaScript ahead-of-time compiler js2asm now passes 88.8% of official ECMAScript 5 test suite. js2.loopdive.com #javascript #webassembly #js #wasm
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