Simon Willison's blog offers a mix of technical tutorials, data analysis projects, and reflections on technology and society. With a focus on Python, SQL, and web development, Simon shares insights into building web applications, working with data, and exploring emerging technologies. Developers can learn about data visualization, API design, and software engineering best practices, gaining inspiration and practical knowledge to advance their careers.

Simon Willison

OpenAI released GPT-5.4 mini and GPT-5.4 nano, two new smaller models joining GPT-5.4. The nano model outperforms the previous GPT-5 mini at maximum reasoning effort, while the mini is 2x faster than its predecessor. Pricing is competitive: gpt-5.4-nano at $0.20/M input tokens is cheaper than Google's Gemini 3.1 Flash-Lite. A practical demo shows describing a museum photo cost under 0.07 cents, meaning 76,000 photos could be described for ~$52. The llm CLI tool (v0.29) was updated to support the new models.

GPT-5.4 mini and GPT-5.4 nano, which can describe 76,000 photos for $52