Simon Willison’s Weblog

The Resource Expert Droid. Like the HTML Validator but for your server’s HTTP headers—extremely useful.

Posted 25th June 2009 at 10:06 am

Recent articles

Hacking the WiFi-enabled color screen GitHub Universe conference badge - 28th October 2025
Video: Building a tool to copy-paste share terminal sessions using Claude Code for web - 23rd October 2025
Dane Stuckey (OpenAI CISO) on prompt injection risks for ChatGPT Atlas - 22nd October 2025

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