Behind the Scenes Hardening Firefox with Claude Mythos Preview (https://hacks.mozilla.org/2026/05/behind-the-scenes-hardening-firefox/) Fascinating, in-depth details on how Mozilla used their access
There weren't a lot of big new announcements from Anthropic at yesterday's Code w/ Claude event, but the biggest by far was the deal they've struck with SpaceX/xAI to use "all of the capacity of
I'm at Anthropic's Code w/ Claude event in 2026, and I'll be live blogging the keynote and a few other notes throughout the day. Tags: ai (https://simonwillison.net/tags/ai),
I recently talked with Joseph Ruscio about AI coding tools for Heavybit's High Leverage podcast: Ep. #9, The AI Coding Paradigm Shift with Simon Willison
Release: datasette-referrer-policy 0.1 (https://github.com/datasette/datasette-referrer-policy/releases/tag/0.1) The OpenStreetMap tiles on the Datasette global-power-plants demo
Our AI started a cafe in Stockholm (https://andonlabs.com/blog/ai-cafe-stockholm) Andon Labs previously started an AI-run retail store (https://andonlabs.com/blog/andon-market-launch) in San
Release: datasette-llm 0.1a7 (https://github.com/datasette/datasette-llm/releases/tag/0.1a7) • Mechanism for configuring default options
Release: llm-echo 0.5a0 (https://github.com/simonw/llm-echo/releases/tag/0.5a0) • New -o thinking 1 option to help test against LLM 0.32a0
So it’s well known that Y Combinator owns some stake in OpenAI. But how big is that stake? This seems like devilishly difficult information to obtain. I asked around and a little birdie who knows
Granite 4.1 3B SVG Pelican Gallery (https://simonw.github.io/granite-4.1-3b-gguf-pelicans/) IBM released their Granite 4.1 family (https://research.ibm.com/blog/granite-4-1-ai-foundation-models) of
[...] Between 2000 and 2024, farmers sold in total a Colorado-sized chunk of land all on their own, 77 times all land on data center property in 2028, and grew more food than ever on what was left.
I just sent out the April 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
Research: TRE Python binding — ReDoS robustness demo (https://github.com/simonw/research/tree/main/tre-python-binding#readme) If it's good enough for antirez
Tool: Redis Array Playground (https://tools.simonwillison.net/redis-array) Salvatore Sanfilippo submitted a PR (https://github.com/redis/redis/pull/15162) adding a new data type - arrays -
We used an automatic classifier which judged sycophancy by looking at whether Claude showed a willingness to push back, maintain positions when challenged, give praise proportional to the merit of
/elsewhere/sightings/ (https://simonwillison.net/elsewhere/sighting/) I have a new camera (a Canon R6 Mark II) so I'm taking a lot more photos of birds. I share my best wildlife photos on
Tool: iNaturalist Sightings (https://tools.simonwillison.net/inat-sightings) I wanted to see my iNaturalist (https://www.inaturalist.org) observations - across two separate accounts - grouped by
Codex CLI 0.128.0 adds /goal (https://github.com/openai/codex/releases/tag/rust-v0.128.0) The latest version of OpenAI's Codex CLI coding agent adds their own version of the Ralph loop
Our evaluation of OpenAI's GPT-5.5 cyber capabilities (https://www.aisi.gov.uk/blog/our-evaluation-of-openais-gpt-5-5-cyber-capabilities) The UK's AI Security Institute previously evaluated Claude
It's a common misconception that we can't tell who is using LLM and who is not. I'm sure we didn't catch 100% of LLM-assisted PRs over the past few months, but the kind of mistakes humans make are