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.
170 articles from this blog
Analysis of Anthropic's Pentagon contract and its branding as a 'moral' AI provider in a commodified AI market.
Explores the importance of manual testing by AI coding agents to complement automated tests, with practical patterns for Python, APIs, and web UIs.
A detailed analysis of a prompt injection attack against Cline's GitHub repo, leading to cache poisoning and a compromised NPM release.
OpenAI announces GPT-5.4 and GPT-5.4-Pro models with enhanced coding, document creation, and a 1M token context window.
Explores the legal and ethical implications of AI coding agents creating "clean room" rewrites to relicense open-source software, using the chardet Python library case.
Reports on high-profile resignations and internal reorganization within Alibaba's Qwen AI team, raising questions about the project's future.
Donald Knuth shares his reaction to an AI solving an open problem he was working on, highlighting advances in AI reasoning.
A skeptic's detailed journey using AI coding agents to port scikit-learn to Rust, showcasing the surprising capabilities of modern LLMs.
Anthropic offers free Claude Max AI access to eligible open source maintainers for six months.
A developer builds a Unicode character lookup tool using binary search over HTTP range requests, with AI assistance.
Explores how AI-generated code creates 'cognitive debt'—a loss of system understanding—which can paralyze developers more than technical debt.
Announcing Interop 2026, a cross-browser initiative by major vendors to improve web platform feature compatibility and parity.
Anthropic's Claude Code creator discusses the evolving role of engineers and why developers are still crucial in the AI era.
Thoughtworks retreat findings challenge the idea that AI replaces junior devs, highlighting their value and the challenges facing mid-level engineers.
Anthropic's public benefit mission as a corporation, detailing its commitment to responsible AI development for humanity's long-term benefit.
Analyzes changes in OpenAI's official mission statement from 2016 to 2024, based on public tax filings, showing a shift in focus and wording.
OpenAI and Cerebras launch GPT-5.3-Codex-Spark, an ultra-fast, text-only AI model for real-time coding with a 128k context window.
Anthropic announces Claude Code's rapid growth, reaching $2.5B run-rate revenue and doubling weekly users in early 2026.
Anthropic pledges to cover grid upgrade costs and electricity price increases caused by its data centers, addressing AI's energy impact.
Google's Gemini 3 Deep Think AI model is tested by generating detailed SVG images of a pelican riding a bicycle, showcasing its capabilities.
