Simon Willison’s Weblog
I recorded a short demo video of my Equal Earth animation on my phone and wanted to publish an optimized version of that video (using FFMPEG) on my blog, so I had Claude Fable 5.1 in Claude Code for web build me this tool using the WebAssembly build of FFMPEG.
Recent articles
The Pelican comparison grid for Astra is pretty interesting - 4th September 2026
OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026
Claude's new system prompt really doesn't want to reproduce song lyrics - 2nd September 2026
This is a beat by Simon Willison, posted on 7th September 2026 .
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