Simon Willison’s Weblog

Hex Fiend. Hex editor for OS X. I could have done with this a few weeks ago.

Posted 28th March 2006 at 10:11 pm

Recent articles

OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025
Useful patterns for building HTML tools - 10th December 2025

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