Simon Willison’s Weblog

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16th December 2025

Tool QuickJS Code Executor — Execute JavaScript code in a sandboxed QuickJS WebAssembly environment with a built-in synchronous `fetch()` function for retrieving remote content. Code is automatically encoded in the URL hash, allowing you to easily share executable snippets with others. The interface provides a collection of ready-to-run examples covering common programming tasks and JavaScript features, making it useful for learning, testing, and demonstrating code behavior.

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This is a beat by Simon Willison, posted on 16th December 2025.

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