Simon Willison

  1. Quoting John Gruber

    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 several OpenAI investors came back with an answer: Y Combinator owns about 0.6 percent of OpenAI. At OpenAI’s…

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  2. Granite 4.1 3B SVG Pelican Gallery

    Granite 4.1 3B SVG Pelican Gallery IBM released their Granite 4.1 family of LLMs a few days ago. They're Apache 2.0 licensed and come in 3B, 8B and 30B sizes. Granite 4.1 LLMs: How They’re Built by Granite team member Yousaf Shah describes the training process in detail. Unsloth released the unsloth…

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  3. Quoting Andy Masley

    [...] 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. None of this caused any problems for US food access. And then, in the middle of all this, a farmer in Loudoun…

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  4. April 2026 newsletter

    I just sent out the April edition of my sponsors-only monthly newsletter. If you are a sponsor (or if you start a sponsorship now) you can access it here. In this month's newsletter: Opus 4.7 and GPT-5.5, both with price increases Claude Mythos and LLM security research ChatGPT Images 2.0 More model…

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  5. TRE Python binding — ReDoS robustness demo

    Research: TRE Python binding — ReDoS robustness demo If it's good enough for antirez to add to Redis I figured Ville Laurikari's TRE regular expression engine was worth exploring in a little more detail. I had Claude Code build an experimental Python binding (it used ctypes) and try some malicious regular…

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  6. Redis Array Playground

    Tool: Redis Array Playground Salvatore Sanfilippo submitted a PR adding a new data type - arrays - to Redis. The new commands are ARCOUNT, ARDEL, ARDELRANGE, ARGET, ARGETRANGE, ARGREP, ARINFO, ARINSERT, ARLASTITEMS, ARLEN, ARMGET, ARMSET, ARNEXT, AROP, ARRING, ARSCAN, ARSEEK, ARSET. The implementation…

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  7. Quoting Anthropic

    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 ideas, and speak frankly regardless of what a person wants to hear. Most of the time in these situations…

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  8. Sightings

    /elsewhere/sightings/ 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 iNaturalist, and based on yesterday's successful prototype I decided to add those to my blog. I built this feature on my phone using Claude Code for web, as an extension…

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  9. iNaturalist Sightings

    Tool: iNaturalist Sightings I wanted to see my iNaturalist observations - across two separate accounts - grouped by when they occurred. I'm camping this weekend so I built this entirely on my phone using Claude Code for web. I started by building an inaturalist-clumper Python CLI for fetching and "clumping…

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  10. Codex CLI 0.128.0 adds /goal

    Codex CLI 0.128.0 adds /goal The latest version of OpenAI's Codex CLI coding agent adds their own version of the Ralph loop: you can now set a /goal and Codex will keep on looping until it evaluates that the goal has been completed... or the configured token budget has been exhausted. It looks like the…

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  11. Our evaluation of OpenAI's GPT-5.5 cyber capabilities

    Our evaluation of OpenAI's GPT-5.5 cyber capabilities The UK's AI Security Institute previously evaluated Claude Mythos: now they've evaluated GPT-5.5 for finding security vulnerability and found it to be comparable to Mythos, but unlike Mythos it's generally available right now. Tags: ai, openai, generative…

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  12. Quoting Andrew Kelley

    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 fundamentally different than LLM hallucinations, making them easy to spot. Furthermore, people who come…

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  13. We need RSS for sharing abundant vibe-coded apps

    We need RSS for sharing abundant vibe-coded apps Matt Webb: I would love an RSS web feed for all those various tools and apps pages, each item with an “Install” button. (But install to where?) The lesson here is that when vibe-coding accelerates app development, apps become more personal, more situated…

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  14. The Zig project's rationale for their firm anti-AI contribution policy

    Zig has one of the most stringent anti-LLM policies of any major open source project: No LLMs for issues. No LLMs for pull requests. No LLMs for comments on the bug tracker, including translation. English is encouraged, but not required. You are welcome to post in your native language and rely on others…

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  15. llm 0.32a1

    Release: llm 0.32a1 Fixed a bug in 0.32a0 where tool-calling conversations were not correctly reinflated from SQLite. #1426 Tags: llm

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  16. LLM 0.32a0 is a major backwards-compatible refactor

    I just released LLM 0.32a0, an alpha release of my LLM Python library and CLI tool for accessing LLMs, with some consequential changes that I've been working towards for quite a while. Previous versions of LLM modeled the world in terms of prompts and responses. Send the model a text prompt, get back…

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  17. llm 0.32a0

    Release: llm 0.32a0 See the annotated release notes. Tags: llm

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  18. Quoting OpenAI Codex base_instructions

    Never talk about goblins, gremlins, raccoons, trolls, ogres, pigeons, or other animals or creatures unless it is absolutely and unambiguously relevant to the user's query. — OpenAI Codex base_instructions, for GPT-5.5 Tags: openai, ai, llms, system-prompts, prompt-engineering, codex-cli, generative-ai…

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  19. Quoting Matthew Yglesias

    Five months in, I think I've decided that I don't want to vibecode — I want professionally managed software companies to use AI coding assistance to make more/better/cheaper software products that they sell to me for money. — Matthew Yglesias Tags: agentic-engineering, vibe-coding, ai-assisted-programming…

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  20. What's new in pip 26.1 - lockfiles and dependency cooldowns!

    What's new in pip 26.1 - lockfiles and dependency cooldowns! Richard Si describes an excellent set of upgrades to Python's default pip tool for installing dependencies. This version drops support for Python 3.9 - fair enough, since it's been EOL since October. macOS still ships with python3 as a default…

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  21. Introducing talkie: a 13B vintage language model from 1930

    Introducing talkie: a 13B vintage language model from 1930 New project from Nick Levine, David Duvenaud, and Alec Radford (of GPT, GPT-2, Whisper fame). talkie-1930-13b-base (53.1 GB) is a "13B language model trained on 260B tokens of historical pre-1931 English text". talkie-1930-13b-it (26.6 GB) is…

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  22. microsoft/VibeVoice

    microsoft/VibeVoice VibeVoice is Microsoft's Whisper-style audio model for speech-to-text, MIT licensed and with speaker diarization built into the model. Microsoft released it on January 21st, 2026 but I hadn't tried it until today. Here's a one-liner to run it on a Mac with uv, mlx-audio (by Prince…

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  23. Tracking the history of the now-deceased OpenAI Microsoft AGI clause

    For many years, Microsoft and OpenAI's relationship has included a weird clause saying that, should AGI be achieved, Microsoft's commercial IP rights to OpenAI's technology would be null and void. That clause appeared to end today. I decided to try and track its expression over time on openai.com. OpenAI…

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  24. Speech translation in Google Meet is now rolling out to mobile devices

    Speech translation in Google Meet is now rolling out to mobile devices I just encountered this feature via a "try this out now" prompt in a Google Meet meeting. It kind-of worked! This is Google's implementation of the ultimate sci-fi translation app, where two people can talk to each other in two separate…

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  25. WHY ARE YOU LIKE THIS

    @scottjla on Twitter in reply to my pelican riding a bicycle benchmark: I feel like we need to stack these tests now I checked to confirm that the model (ChatGPT Images 2.0) added the "WHY ARE YOU LIKE THIS" sign of its own accord and it did - the prompt Scott used was: Create an image of a horse riding…

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  26. Quoting Romain Huet

    Since GPT-5.4, we’ve unified Codex and the main model into a single system, so there’s no separate coding line anymore. GPT-5.5 takes this further, with strong gains in agentic coding, computer use, and any task on a computer. — Romain Huet, confirming OpenAI won't release a GPT-5.5-Codex model Tags…

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  27. GPT-5.5 prompting guide

    GPT-5.5 prompting guide Now that GPT-5.5 is available in the API, OpenAI have released a wealth of useful tips on how best to prompt the new model. Here's a neat trick they recommend for applications that might spend considerable time thinking before returning a user-visible response: Before any tool…

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  28. llm 0.31

    Release: llm 0.31 New GPT-5.5 OpenAI model: llm -m gpt-5.5. #1418 New option to set the text verbosity level for GPT-5+ OpenAI models: -o verbosity low. Values are low, medium, high. New option for setting the image detail level used for image attachments to OpenAI models: -o image_detail low - values…

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  29. The people do not yearn for automation

    The people do not yearn for automation This written and video essay by Nilay Patel explores why AI is unpopular with the general public even as usage numbers for ChatGPT continue to skyrocket. It’s a superb piece of commentary, and something I expect I’ll be thinking about for a long time to come. Nilay’s…

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  30. DeepSeek V4 - almost on the frontier, a fraction of the price

    Chinese AI lab DeepSeek's last model release was V3.2 (and V3.2 Speciale) last December. They just dropped the first of their hotly anticipated V4 series in the shape of two preview models, DeepSeek-V4-Pro and DeepSeek-V4-Flash. Both models are 1 million token context Mixture of Experts. Pro is 1.6T…

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