SimonWillison.net is the long-running blog of Simon Willison, a software engineer, open-source creator, and co-author of the original Django framework. He writes about Python, Django, Datasette, AI tooling, prompt engineering, search, databases, APIs, data journalism, and practical software architecture. The blog includes detailed notes from experiments, conference talks, and real projects. Readers will find clear explanations of topics such as LLM workflows, SQL patterns, data publishing, scraping, deployment, caching, and modern developer tooling. Simon also publishes frequent micro-posts and TIL entries that document small discoveries and tricks from day-to-day engineering work. The tone is practical and research oriented, making the site a valuable resource for anyone interested in serious engineering and open data.
260 articles from this blog
DeepSeek-Math-V2 is an open-source 685B parameter AI model that achieves gold medal performance on mathematical Olympiad problems.
Simon Willison discusses data journalism, Django's origins, and tech's role in news on the Data Renegades podcast.
Analysis of a prompt injection vulnerability in Google's Antigravity IDE that can exfiltrate AWS credentials and sensitive code data.
LLVM 21 adds constant-time support to protect cryptographic code from timing attacks at the compiler level.
Release of llm-anthropic 0.23 plugin adding support for Claude Opus 4.5 and its new thinking_effort option.
A benchmark comparing 9 AI models on their ability to generate SVG images from creative text prompts like 'an octopus operating a pipe organ'.
Analysis of a leaked system prompt for Claude Opus 4.5, discussing its content and the challenges of evaluating new LLMs.
Analysis of Claude Opus 4.5 LLM release and the growing difficulty in evaluating incremental improvements between AI models.
Release notes for sqlite-utils 3.39, featuring bug fixes for plugin installation with uv and new functionality for custom SQL functions.
Announcing sqlite-utils 4.0a1, a Python library and CLI for SQLite, detailing minor backwards incompatible changes before the stable release.
Analysis of how engineering management trends shift with business cycles, highlighting core skills that remain constant.
Armin Ronacher discusses challenges in AI agent design, including abstraction issues, testing difficulties, and API synchronization problems.
Olmo 3 is a new fully open-source large language model from AI2, featuring training data, code, and unique interpretability for reasoning traces.
Explains dependency cooldowns, a strategy to reduce supply chain attack risk by delaying automatic dependency updates.
Analysis of Google's new Nano Banana Pro image generation model, covering its advanced features, API pricing, and real-world testing results.
Explores how LLMs could enable malware to find personal secrets for blackmail, moving beyond simple ransomware attacks.
OpenAI releases GPT-5.1-Codex-Max, a new AI model focused on agentic coding tasks, featuring advanced context compaction for long-running work.
A developer explains his automated workflow using SQL, Datasette, and Observable to generate a Substack newsletter from his blog content.
Analysis of a major Cloudflare outage caused by a database permissions change and software panic, quoting CEO Matthew Prince.
New release of the llm-gemini plugin adds support for nested Pydantic schemas, YouTube URL attachments, and the latest Gemini 3 Pro model.
