Simon Willison’s Weblog

Implementing a syntax-higlighting JavaScript editor in JavaScript. Appropriately subtitled “a brutal odyssey to the dark side of the DOM tree”. Some seriously clever trickery going on here.

Posted 4th April 2008 at 8:27 am

Recent articles

JustHTML is a fascinating example of vibe engineering in action - 14th December 2025
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025

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