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

Generating running routes with GPT-6 Astra and ChatGPT Work - 12th September 2026
OpenAI agents attacked RubyGems back in May - 12th September 2026
Some thoughts on the Navier–Stokes Millennium Prize Problem - 8th September 2026

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

ai 2,239 openai 464 generative-ai 1,985 llms 1,951 ai-assisted-programming 407 anthropic 337 claude 311 claude-4 14 gpt-5 31 november-2025-inflection 16 gpt 131

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