Simon Willison’s Weblog

4th January 2026

It genuinely feels to me like GPT-5.2 and Opus 4.5 in November represent an inflection point - one of those moments where the models get incrementally better in a way that tips across an invisible capability line where suddenly a whole bunch of much harder coding problems open up.

Posted 4th January 2026 at 11:21 pm

Recent articles

Publishing WASM wheels to PyPI for use with Pyodide - 13th June 2026
Claude Fable is relentlessly proactive - 11th June 2026
Initial impressions of Claude Fable 5 - 9th June 2026

This is a note by Simon Willison, posted on 4th January 2026.

anthropic 299 claude 284 openai 423 ai 2,076 llms 1,801 gpt-5 30 ai-assisted-programming 387 generative-ai 1,833 claude-4 14 november-2025-inflection 15 gpt 124

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