SimonWillison.net is the long-running blog of Simon Willison, a software engineer, open-source creator, and co-author of the original Django framework. He writes about Python, Django, Datasette, AI tooling, prompt engineering, search, databases, APIs, data journalism, and practical software architecture. The blog includes detailed notes from experiments, conference talks, and real projects. Readers will find clear explanations of topics such as LLM workflows, SQL patterns, data publishing, scraping, deployment, caching, and modern developer tooling. Simon also publishes frequent micro-posts and TIL entries that document small discoveries and tricks from day-to-day engineering work. The tone is practical and research oriented, making the site a valuable resource for anyone interested in serious engineering and open data.
287 articles from this blog
Anthropic's Claude Opus 4.6 and Sonnet 4.6 models now offer 1M context at standard pricing, contrasting with competitors' long-context premiums.
A developer builds custom accounting software to handle complex multi-currency, tax, and data ingestion needs, finding it superior to off-the-shelf solutions.
Shopify CEO uses AI coding agent to achieve 53% faster parse+render and 61% fewer allocations in the Liquid template engine.
Satirical article about a fictional AI service that recreates open source projects to bypass licensing obligations.
Explores the transformative impact of AI on software development, featuring insights from industry experts on the future of coding.
AI-assisted coding reveals a philosophical divide between developers who prioritize craft and those focused on results.
Creating animated visualizations of sorting algorithms using AI tools, including Python's Timsort.
A quote from John Carmack on the pitfalls of over-architecting software for future needs.
Argues that AI coding agents can help developers produce higher quality code and reduce technical debt by automating tedious refactoring tasks.
New PostgreSQL 18 and SQLite features allow developers to copy database statistics to test production query plans without moving large datasets.
Explores how modern LLM coding agents adapt to new or private tools, challenging the 'Choose Boring Technology' assumption.
A quote from Joseph Weizenbaum on how simple computer programs can induce delusional thinking in people, shared on a tech blog.
OpenAI offers 6 months of ChatGPT Pro with Codex to core maintainers of significant open source projects, following a similar move by Anthropic.
Key questions for developers, managers, and stakeholders to audit a software codebase and identify process issues.
Analysis of Anthropic's Pentagon contract and its strategy to brand itself as the ethical AI provider in a commodified 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, exploiting AI issue triage to poison caches and compromise production releases.
OpenAI announces GPT-5.4 and GPT-5.4-Pro models with improved 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 within Alibaba's Qwen AI team, including its lead researcher, raising questions about the project's future.
