Simon Willison’s Weblog

Use HTML 4.01, not XHTML. Why Stuart’s book uses HTML, not XHTML.

Posted 21st February 2005 at 12:52 pm

Recent articles

Reverse engineering Codex CLI to get GPT-5-Codex-Mini to draw me a pelican - 9th November 2025
Video + notes on upgrading a Datasette plugin for the latest 1.0 alpha, with help from uv and OpenAI Codex CLI - 6th November 2025
Code research projects with async coding agents like Claude Code and Codex - 6th November 2025

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