Simon Willison — Independent developer and writer documenting practical experiments, tools, and deep analysis around large language models, generative AI, web development, security, and emerging programming workflows through detailed posts and daily TILs.
86 articles from this blog
Anthropic publicly releases Claude AI's internal 'constitution', a lengthy document detailing its core values and training principles.
Analysis of the electricity consumption of AI coding agents like Claude Code, comparing it to daily household appliance usage.
A university professor describes an open-book exam where students could use chatbots, analyzing the low adoption rate and student motivations.
Explores NanoLang, a new programming language designed for LLMs, and tests AI's ability to generate working code in it.
Experiments with AI coding agents building a web browser from scratch, generating over a million lines of code in a week.
A pure C, dependency-free implementation of the FLUX.2-klein-4B AI model, created with AI assistance.
Jeremy Daer discusses why CLI tools are better than REST APIs for AI agents, citing accuracy, cost, and model accessibility.
OpenAI announces ads for ChatGPT's free and Go tiers, plus a new pricing structure, while assuring ad independence and user privacy.
Introduces Open Responses, a vendor-neutral JSON API standard for hosted LLMs, based on OpenAI's Responses API and backed by major industry partners.
Explains the technical design of Fly.io's Sprites, focusing on fast provisioning via warm pools and a custom persistence layer using JuiceFS and SQLite.
OpenAI researchers propose 'confessions' as a method to improve AI honesty by training models to self-report misbehavior in reinforcement learning.
A security vulnerability in Claude Cowork allowed file exfiltration via the Anthropic API, bypassing default HTTP restrictions.
Anthropic invests $1.5 million in the Python Software Foundation to support Python ecosystem security and core development.
A prompt injection attack on Superhuman AI exposed sensitive emails, highlighting a critical security vulnerability in AI email assistants.
A hands-on review of Anthropic's new Claude Cowork agent, exploring its interface, capabilities, and potential as a general AI assistant for non-developers.
Argues against anti-AI sentiment in software development, stating AI is a permanent, useful tool that will democratize coding and improve productivity.
Author explores the legal and ethical implications of using LLMs to port open source code between programming languages, based on personal experiments.
A blog post quoting Linus Torvalds on using AI-assisted 'vibe-coding' to create a Python audio visualizer tool.
An experiment in creating a software library with no code, using AI agents to generate implementations from specifications and tests.
Fly.io launches Sprites.dev, a stateful sandbox environment for secure coding agents and untrusted code execution.
