AIGenerated AI news, written by AI and explained simply. Models, technology, culture and the people behind it.
Simon Willison is a developer and writer known for building practical AI tools and sharing clear perspectives on how artificial intelligence is changing software.
7 stories, first covered on Oct 11, 2026.
Simon Willison is a software developer who has spent years exploring how AI can be used in everyday programming and data work. He is best known for building small, focused tools that help developers navigate the rapidly changing AI landscape.
He shares his work and thinking on public forums such as Hacker News, where his posts regularly attract attention from the developer community. His topics range from how AI is reshaping software development to practical implementations of autonomous coding systems.
One of his most recognized projects is ttok, a tool that counts tokens for AI language models. In an October 2026 update, he released ttok 1.0, which changed its default setting to use the tokenizer shared by OpenAI's GPT-5 and GPT-6 models. This update came after testing confirmed the two models use the same token counting system, making the tool more useful for developers working with the latest OpenAI releases.
Willison has also showcased OctopusGarden, described as an autonomous software factory that takes specifications as input and produces code as output. This project reflects his ongoing interest in how AI can automate routine development tasks.
Willison's work sits at a practical intersection: he builds tools developers actually use while also examining broader trends in AI and software. His contributions help developers keep pace with model updates and explore new ways AI can assist in coding workflows.
His perspective has also been featured on podcasts such as the Talking Postgres podcast, where he discussed applying AI to data engineering tasks.
He is known for building practical developer tools for the AI era, most notably ttok, a token counting tool updated for newer OpenAI models. He also explores autonomous software generation and how AI is changing development workflows.
ttok is a token counting tool that helps developers estimate how many tokens their prompts and responses use in AI models. It was updated in October 2026 to default to the tokenizer used by GPT-5 and GPT-6, after testing showed the two models share the same token counting system.
He shares his projects and commentary on public platforms like Hacker News and has appeared on podcasts such as the Talking Postgres podcast discussing AI applications for data engineering.
PeopleSimon Willison builds two-player pong game that communicates via audio chirpsHerald of AI
The AI educator used Claude Opus 5.5 to create a game where two phones exchange moves through sounds played through the microphone.
PeopleSimon Willison Codes a Game With One Prompt to ClaudeHerald of AI
A blogger proved that 'vibe coding' can produce a surprisingly polished Three.js game in just one conversation.
PeopleSimon Willison releases web-edit for browser-based file editingHerald of AIPaul Downey from Berkhamsted, UK, CC BY 2.0, via Wikimedia Commons
His new tool lets you edit files in a folder straight from your browser, with help from Claude Opus 5.5.
PeopleSimon Willison Updates llm-gemini to Support New Gemini 4 Argon ModelHerald of AI
The developer behind the popular llm plugin adds Google's latest low-cost model, which promises strong performance at a fraction of rival prices — at least until December.
How it worksNew Plugin Lets You Use Meta’s Muse Wonder AI ModelsHerald of AI
Simon Willison updated his llm-meta-ai tool to work with Meta’s latest top-tier reasoning models.
How it worksAnthropic rebuilt its code system to handle 10x growth in daily changesHerald of AI
Anthropic replaced Git with a custom tool called Scion after its daily code merges jumped from 2,500 to over 30,000 in just four months.
How it worksttok 1.0 Updates Token Counting Tool to Match New OpenAI ModelsHerald of AIPaul Downey from Berkhamsted, UK, CC BY 2.0, via Wikimedia Commons
Simon Willison releases an updated tool that now defaults to the tokenizer used by GPT-5 and GPT-6, after a recent experiment confirmed they share the same system.