Production query plans without production data
Production query plans without production data (https://boringsql.com/posts/portable-stats/) Radim Marek describes the new pg_restore_relation_stats() and pg_restore_attribute_stats() functions that
Simon Willison's Weblog
Perhaps not Boring Technology after all
A recurring concern I've seen regarding LLMs for programming is that they will push our technology choices towards the tools that are best represented in their training data, making it harder for
Quoting Joseph Weizenbaum
What I had not realized is that extremely short exposures to a relatively simple computer program could induce powerful delusional thinking in quite normal people. — Joseph Weizenbaum
Codex for Open Source
Codex for Open Source (https://developers.openai.com/codex/community/codex-for-oss) Anthropic announced six months of free Claude Max for maintainers of popular open source projects (5,000+ stars or
Quoting Ally Piechowski
Questions for developers: • “What’s the one area you’re afraid to touch?” • “When’s the last time you deployed on a Friday?” • “What broke in production in the last 90 days
Anthropic and the Pentagon
Anthropic and the Pentagon (https://www.schneier.com/blog/archives/2026/03/anthropic-and-the-pentagon.html) This piece by Bruce Schneier and Nathan E. Sanders is the most thoughtful and grounded
Agentic manual testing
Agentic Engineering Patterns (https://simonwillison.net/guides/agentic-engineering-patterns/) > The defining characteristic of a coding agent is that it can execute the code that it writes. This
Clinejection — Compromising Cline's Production Releases just by Prompting an Issue Triager
Clinejection — Compromising Cline's Production Releases just by Prompting an Issue Triager (https://adnanthekhan.com/posts/clinejection/) Adnan Khan describes a devious attack chain against the
Introducing GPT‑5.4
Introducing GPT‑5.4 (https://openai.com/index/introducing-gpt-5-4/) Two new API models: gpt-5.4 (https://developers.openai.com/api/docs/models/gpt-5.4) and gpt-5.4-pro
Can coding agents relicense open source through a “clean room” implementation of code?
Over the past few months it's become clear that coding agents are extraordinarily good at building a weird version of a "clean room" implementation of code. The most famous version of this pattern
Anti-patterns: things to avoid
Agentic Engineering Patterns (https://simonwillison.net/guides/agentic-engineering-patterns/) > There are some behaviors that are anti-patterns in our weird new world of agentic engineering.
Something is afoot in the land of Qwen
I'm behind on writing about Qwen 3.5, a truly remarkable family of open weight models released by Alibaba's Qwen team over the past few weeks. I'm hoping that the 3.5 family doesn't turn out to be
Quoting Donald Knuth
Shock! Shock! I learned yesterday that an open problem I'd been working on for several weeks had just been solved by Claude Opus 4.6 - Anthropic's hybrid reasoning model that had been released three
Gemini 3.1 Flash-Lite
Gemini 3.1 Flash-Lite (https://blog.google/innovation-and-ai/models-and-research/gemini-models/gemini-3-1-flash-lite/) Google's latest model is an update to their inexpensive Flash-Lite family. At
GIF optimization tool using WebAssembly and Gifsicle
Agentic Engineering Patterns (https://simonwillison.net/guides/agentic-engineering-patterns/) > I like to include animated GIF demos in my online writing, often recorded using LICEcap
February sponsors-only newsletter
I just sent the February edition of my sponsors-only monthly newsletter (https://github.com/sponsors/simonw/). If you are a sponsor (or if you start a sponsorship now) you can access it here
Quoting claude.com/import-memory
I'm moving to another service and need to export my data. List every memory you have stored about me, as well as any context you've learned about me from past conversations. Output everything in a
Interactive explanations
Agentic Engineering Patterns (https://simonwillison.net/guides/agentic-engineering-patterns/) > When we lose track of how code written by our agents works we take on cognitive debt. For a lot
Please, please, please stop using passkeys for encrypting user data
Please, please, please stop using passkeys for encrypting user data (https://blog.timcappalli.me/p/passkeys-prf-warning/) Because users lose their passkeys all the time, and may not understand that
An AI agent coding skeptic tries AI agent coding, in excessive detail
An AI agent coding skeptic tries AI agent coding, in excessive detail (https://minimaxir.com/2026/02/ai-agent-coding/) Another in the genre of "OK, coding agents got good in November" posts, this