Simon Willison's Weblog
One Human + One Agent = One Browser From Scratch
Kimi K2.5: Visual Agentic Intelligence
Tips for getting coding agents to write good Python tests
ChatGPT Containers can now run bash, pip/npm install packages, and download files
the browser is the sandbox
Kākāpō Cam: Rakiura live stream
Don't "Trust the Process"
Quoting Jasmine Sun
Wilson Lin on FastRender: a browser built by thousands of parallel agents
Quoting Theia Vogel
SSH has no Host header
Qwen3-TTS Family is Now Open Sourced: Voice Design, Clone, and Generation
Quoting Thariq Shihipar
Quoting Chris Lloyd
Claude's new constitution
Electricity use of AI coding agents
Giving University Exams in the Age of Chatbots
jordanhubbard/nanolang
Scaling long-running autonomous coding
FLUX.2-klein-4B Pure C Implementation
Quoting Jeremy Daer
Our approach to advertising and expanding access to ChatGPT
Open Responses
The Design & Implementation of Sprites
Quoting Boaz Barak, Gabriel Wu, Jeremy Chen and Manas Joglekar
Claude Cowork Exfiltrates Files
Anthropic invests $1.5 million in the Python Software Foundation and open source security
Superhuman AI Exfiltrates Emails
First impressions of Claude Cowork, Anthropic's general agent
Don't fall into the anti-AI hype
My answers to the questions I posed about porting open source code with LLMs
TIL from taking Neon I at the Crucible
Quoting Linus Torvalds
A Software Library with No Code
Fly's new Sprites.dev addresses both developer sandboxes and API sandboxes at the same time
LLM predictions for 2026, shared with Oxide and Friends
How Google Got Its Groove Back and Edged Ahead of OpenAI
Quoting Adam Wathan
Quoting Robin Sloan
A field guide to sandboxes for AI
It’s hard to justify Tahoe icons
Oxide and Friends Predictions 2026, today at 4pm PT
The November 2025 inflection point
Quoting Addy Osmani
Helping people write code again
Quoting Jaana Dogan
Was Daft Punk Having a Laugh When They Chose the Tempo of Harder, Better, Faster, Stronger?
Quoting Will Larson
The most popular blogs of Hacker News in 2025
December 2025 sponsors-only newsletter
Quoting Ben Werdmuller
Introducing gisthost.github.io
2025: The year in LLMs
Codex cloud is now called Codex web
Quoting Armin Ronacher
TIL: Downloading archived Git repositories from archive.softwareheritage.org
Quoting Liz Fong-Jones
shot-scraper 1.9
Quoting D. Richard Hipp
Quoting Jason Gorman
Copyright Release for Contributions To SQLite
Quoting Aaron Levie
simonw/actions-latest
Substack Network error = security content they don't allow to be sent
Pluribus training data
Quoting Boris Cherny
textarea.my on GitHub
How uv got so fast
How Rob Pike got spammed with an AI slop "act of kindness"
A new way to extract detailed transcripts from Claude Code
uv-init-demos
Quoting Salvatore Sanfilippo
MicroQuickJS
Cooking with Claude
Using Claude in Chrome to navigate out the Cloudflare dashboard
Quoting Shriram Krishnamurthi
Quoting Andrej Karpathy
Sam Rose explains how LLMs work with a visual essay
Introducing GPT-5.2-Codex
Agent Skills
swift-justhtml
Your job is to deliver code you have proven to work
Inside PostHog: How SSRF, a ClickHouse SQL Escaping 0day, and Default PostgreSQL Credentials Formed an RCE Chain
AoAH Day 15: Porting a complete HTML5 parser and browser test suite
Gemini 3 Flash
firefox parser/html/java/README.txt
The new ChatGPT Images is here
s3-credentials 0.17
ty: An extremely fast Python type checker and LSP
Poe the Poet
Quoting Gemini thinking trace
Quoting Kent Beck
I ported JustHTML from Python to JavaScript with Codex CLI and GPT-5.2 in 4.5 hours
2025 Word of the Year: Slop
JustHTML is a fascinating example of vibe engineering in action
Copywriters reveal how AI has decimated their industry
Quoting Obie Fernandez
Quoting OpenAI Codex CLI
OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI
LLM 0.28
GPT-5.2
Useful patterns for building HTML tools
The Normalization of Deviance in AI
Dark mode
10 Years of Let's Encrypt
Devstral 2
Under the hood of Canada Spends with Brendan Samek
Agentic AI Foundation
mistralai/mistral-vibe
Quoting Claude
Prediction: AI will make formal verification go mainstream
Deprecations via warnings don’t work for Python libraries
Niche Museums: The Museum of Jurassic Technology
Quoting Cory Doctorow
Using LLMs at Oxide
Quoting David Crespo
The Unexpected Effectiveness of One-Shot Decompilation with Claude
Quoting Daniel Lemire
TIL: Subtests in pytest 9.0.0+
Thoughts on Go vs. Rust vs. Zig
The Resonant Computing Manifesto
Django 6.0 released
Text a community college librarian
Quoting Mitchell Hashimoto
TIL: Dependency groups and uv run
Anthropic acquires Bun
Introducing Mistral 3
Claude 4.5 Opus' Soul Document
DeepSeek-V3.2
I sent out my November sponsor newsletter
Quoting David Bauder, AP News
YouTube embeds fail with a 153 error
Quoting Felix Nolan
ChatGPT is three years old today
Quoting Rodrigo Arias Mallo
Context plumbing
Quoting Wikipedia content guideline
A ChatGPT prompt equals about 5.1 seconds of Netflix
Bluesky Thread Viewer thread by @simonwillison.net
Quoting Qwen3-VL Technical Report
deepseek-ai/DeepSeek-Math-V2
Highlights from my appearance on the Data Renegades podcast with CL Kao and Dori Wilson
Google Antigravity Exfiltrates Data
Constant-time support lands in LLVM: Protecting cryptographic code at the compiler level
llm-anthropic 0.23
LLM SVG Generation Benchmark
Quoting Claude Opus 4.5 system prompt
Claude Opus 4.5, and why evaluating new LLMs is increasingly difficult
sqlite-utils 3.39
sqlite-utils 4.0a1 has several (minor) backwards incompatible changes
"Good engineering management" is a fad
Agent design is still hard
Olmo 3 is a fully open LLM
We should all be using dependency cooldowns
Nano Banana Pro aka gemini-3-pro-image-preview is the best available image generation model
Quoting Nicholas Carlini
Building more with GPT-5.1-Codex-Max
How I automate my Substack newsletter with content from my blog
Quoting Matthew Prince
llm-gemini 0.27
MacWhisper has Automatic Speaker Recognition now
Google Antigravity
Quoting Ethan Mollick
Trying out Gemini 3 Pro with audio transcription and a new pelican benchmark
The fate of “small” open source
Quoting Andrej Karpathy
llm-anthropic 0.22
parakeet-mlx
GPT-5.1 Instant and GPT-5.1 Thinking System Card Addendum
Introducing GPT-5.1 for developers
Datasette 1.0a22
Nano Banana can be prompt engineered for extremely nuanced AI image generation
Quoting Nov 12th letter from OpenAI to Judge Ona T. Wang
What happens if AI labs train for pelicans riding bicycles?
Quoting Steve Krouse
Fun-reliable side-channels for cross-container communication
Scaling HNSWs
Agentic Pelican on a Bicycle
Six coding agents at once
Quoting Netflix
Pelican on a Bike - Raytracer Edition
Reverse engineering Codex CLI to get GPT-5-Codex-Mini to draw me a pelican
Quoting Kenton Varda
Mastodon 4.5
Quoting Josh Cohenzadeh
Could LLMs encourage new programming languages?
Using Codex CLI with gpt-oss:120b on an NVIDIA DGX Spark via Tailscale
Game design is simple, actually
You should write an agent
Quoting Ben Stolovitz
Kimi K2 Thinking
Quoting Nathan Lambert
Video + notes on upgrading a Datasette plugin for the latest 1.0 alpha
Code research projects with async coding agents like Claude Code and Codex
Open redirect endpoint in Datasette prior to 0.65.2 and 1.0a21
Removing XSLT for a more secure browser
Quoting @belligerentbarbies
Code execution with MCP: Building more efficient agents
A new SQL-powered permissions system in Datasette 1.0a20
MCP Colors: Systematically deal with prompt injection risk
Quoting Steve Francia
The fetch()ening
Quoting Barry Warsaw
The case against pgvector
Quoting MiniMax
New prompt injection papers: Agents Rule of Two and The Attacker Moves Second
PyCon US 2026 call for proposals is now open
How I Use Every Claude Code Feature
Claude Code Can Debug Low-level Cryptography
October 2025 sponsors-only newsletter
Quoting Julian Andres Klode
Curiosity-driven blogging
CoreWeave adds Marimo to their 2025 acquisition spree
Quoting François Chollet
Introducing SWE-1.5: Our Fast Agent Model
MiniMax M2 & Agent: Ingenious in Simplicity
Composer: Building a fast frontier model with RL
Hacking the WiFi-enabled color screen GitHub Universe conference badge
Quoting Aaron Boodman
The PSF has withdrawn a $1.5 million proposal to US government grant program
GenAI Image Editing Showdown
Sora might have a 'pervert' problem on its hands
Setting up a codebase for working with coding agents
Quoting Claude Docs
Visual Features Across Modalities: SVG and ASCII Art Reveal Cross-Modal Understanding
claude_code_docs_map.md
Quoting Geoffrey Litt
OpenAI no longer has to preserve all of its ChatGPT data, with some exceptions
Quoting AWS
Video: Building a tool to copy-paste share terminal sessions using Claude Code for web
Dane Stuckey (OpenAI CISO) on prompt injection risks for ChatGPT Atlas
Living dangerously with Claude
SLOCCount in WebAssembly
Don't let Claude Code delete your session logs
Unseeable prompt injections in screenshots: more vulnerabilities in Comet and other AI browsers
Introducing ChatGPT Atlas
Quoting Phil Gyford
Quoting Bruce Schneier and Barath Raghavan
Claude Code for web - a new asynchronous coding agent from Anthropic
Getting DeepSeek-OCR working on an NVIDIA Spark via brute force using Claude Code
TIL: Exploring OpenAI's deep research API model o4-mini-deep-research
The AI water issue is fake
Andrej Karpathy — AGI is still a decade away
Quoting Alexander Fridriksson and Jay Miller
Should form labels be wrapped or separate?
Quoting Barry Zhang
Claude Skills are awesome, maybe a bigger deal than MCP
NVIDIA DGX Spark + Apple Mac Studio = 4x Faster LLM Inference with EXO 1.0
Quoting Riana Pfefferkorn
Coding without typing the code
Quoting Catherine Wu
Introducing Claude Haiku 4.5
Quoting Claude Haiku 4.5 System Card
A modern approach to preventing CSRF in Go
NVIDIA DGX Spark: great hardware, early days for the ecosystem
Just Talk To It - the no-bs Way of Agentic Engineering
nanochat
Quoting Slashdot
Claude Code sub-agents
Vibing a Non-Trivial Ghostty Feature
Note on 11th October 2025
An MVCC-like columnar table on S3 with constant-time deletes
simonw/claude-skills
Superpowers: How I'm using coding agents in October 2025
A Retrospective Survey of 2024/2025 Open Source Supply Chain Compromises
Video of GPT-OSS 20B running on a phone
Quoting Gergely Orosz
TIL: Testing different Python versions with uv with-editable and uv-test
Claude can write complete Datasette plugins now
Python 3.14 Is Here. How Fast Is It?
Quoting Simon Højberg
Why NetNewsWire Is Not a Web App
Python 3.14
Gemini 2.5 Computer Use can solve Google's own CAPTCHAs
Quoting Thomas Klausner
Vibe engineering
Deloitte to pay money back to Albanese government after using AI in $440,000 report
a system that can do work independently on behalf of the user
gpt-image-1-mini
GPT-5 pro
OpenAI DevDay 2025 live blog
Quoting Tim Berners-Lee
Bad bots
Embracing the parallel coding agent lifestyle
Let the LLM Write the Prompts: An Intro to DSPy in Compound Al Pipelines
Litestream v0.5.0 is Here
Sora 2 prompt injection
Daniel Stenberg's note on AI assisted curl bug reports
Quoting Nadia Eghbal
aavetis/PRarena
Two more Chinese pelicans
September monthly sponsors newsletter
Sora 2
Designing agentic loops
Claude Sonnet 4.5 is probably the "best coding model in the world" (at least for now)
Armin Ronacher: 90%
Quoting Scott Aaronson
Quoting Nick Turley
Video models are zero-shot learners and reasoners
Quoting Dan Abramov
ForcedLeak: AI Agent risks exposed in Salesforce AgentForce
How to stop AI’s “lethal trifecta”
GitHub Copilot CLI is now in public preview
Improved Gemini 2.5 Flash and Flash-Lite
Don't hide your best documentation
Quoting Stanford CS221 Autumn 2025
Cross-Agent Privilege Escalation: When Agents Free Each Other
GPT-5-Codex
Qwen3-VL: Sharper Vision, Deeper Thought, Broader Action
Why AI systems might never be secure
Quoting Kate Niederhoffer, Gabriella Rosen Kellerman, Angela Lee, Alex Liebscher, Kristina Rapuano and Jeffrey T. Hancock
Four new releases from Qwen
CompileBench: Can AI Compile 22-year-old Code?
ChatGPT Is Blowing Up Marriages as Spouses Use AI to Attack Their Partners
Locally AI