# simon-willison

Django co-creator Simon Willison gave Lenny's Podcast a broad AI status report: November 2025 as tipping point, coding agents burning him out by 11 AM, Dark Factories, mid-career risk, and the security pattern he calls the Lethal Trifecta.

Simon Willison published his full workshop handout from NICAR's data journalism conference — a three-hour guide to using coding agents like Codex CLI and Claude Code for data exploration, visualization, and analysis.

Simon Willison finally defines Agentic Engineering after 11 hands-on chapters: using coding agents to help build software. The interesting part is why he needed the patterns first before the simple definition felt earned.

Simon Willison's Agentic Engineering Patterns, Chapter 3: AI should help us ship better code, not worse. Technical debt cleanup costs near zero now, architecture decisions can be validated with prototypes instead of guesses, and quality compounds over time.

Simon Willison's First Run the Tests pattern is four words with three effects: the agent learns the test command, gauges codebase size, and shifts into a test-maintenance mindset. Tiny instruction, large behavioral nudge.

Simon Willison shared his agentic engineering playbook at the Pragmatic Summit — five tokens to start TDD, Showboat for manual verification, reverse-engineering six frameworks into a standard, and why bad code is a choice you make.

Simon Willison's new Agentic Engineering anti-pattern hits hard: do not submit AI-generated code you have not personally verified. That is not saving time; it is stealing reviewer time. The post pairs principles with a terraform destroy horror story.

Simon Willison introduces Agentic Manual Testing: let AI agents manually operate code and UI like humans do, catching bugs that automated tests miss. With Playwright, Rodney, and Showboat, the 'tests pass but it's broken' nightmare becomes a thing of the past.

Chapter 5 of Simon Willison's Agentic Engineering Patterns: Interactive Explanations. Core thesis: instead of staring at AI-generated code trying to understand it, ask your agent to build an interactive animation that shows you how the algorithm works. Pay down cognitive debt visually.

Chapter 4 of Simon Willison's Agentic Engineering Patterns: Hoard Things You Know How to Do. Core thesis: every problem you've solved should leave behind working code, because coding agents can recombine your old solutions into things you never imagined.

Chapter 3 of Simon Willison's Agentic Engineering Patterns: the Linear Walkthrough pattern. This technique transforms even vibe-coded toy projects into valuable learning resources. Core trick: make the agent use sed/grep/cat to fetch code snippets, preventing hallucination.

Simon Willison tried Claude Code Remote Control and Cowork Scheduled Tasks — two Anthropic features that overlap with OpenClaw, both requiring your computer to stay on. Plus: vibe-coding a SwiftUI presentation app in 45 minutes with Tailscale phone remote control.

Simon Willison launched Agentic Engineering Patterns, a playbook for coding agents like Claude Code and Codex. Lesson one: writing code got cheap, but good code remains expensive. Lesson two: red/green TDD is the six-word spell.

Simon Willison added a 'Beats' feature to his blog, pulling TILs, GitHub releases, museum posts, tools, and research back into one unified timeline. This isn't a UI tweak — it's a systematic approach to making all your small outputs visible and compounding.

SWE-bench: Claude Opus 4.5 (76.8%) unexpectedly beat 4.6 (75.6%) for #1. MiniMax M2.5 tied for #2 at 1/20th Opus's price, with 4 Chinese models in top 10. GPT-5.3-Codex missed due to no API. Bonus: Claude for Chrome to add chart labels.

Simon Willison argues CLI tools beat MCP for coding agents in most cases: lower token cost, no extra dependencies, and native --help affordances. Anthropic's code-execution-with-MCP proposal admits the token-waste problem too.

AI writing better code? That "Deep Blue" feeling, coined by Simon Willison & Adam Leventhal (Oxide & Friends), means IBM's chess computer & the color of sadness. It's not just a tech problem, but a psychological crisis for engineers.

Technical debt lives in code, cognitive debt in your brain. As AI writes 80% of code, system understanding drops to 20%. UVic's Margaret-Anne Storey, Simon Willison, & Martin Fowler confirm this isn't a hypothetical future—it's happening now.

Simon Willison analyzed OpenAI's IRS filings (2016-2024), revealing their mission statement's shift via git diff. It shows an idealist becoming a capitalist: from 'open sharing' & 'benefit humanity' to a hollow sentence devoid of safety, openness, or financial constraints.

OpenAI's Responses API now uses 'Skills' via the shell tool: reusable instruction bundles loaded by models as needed. Simon Willison found inline base64 skills in JSON requests neatest. Skills fill the 'missing middle layer' between system prompts and tools, preventing bloat.

Chinese AI company Zhipu (Z.ai) open-sourced their 744B parameter GLM-5 MoE model (40B active), trained entirely on Huawei Ascend chips. Simon Willison's 'pelican riding a bicycle' SVG test: great pelican, but the bicycle was lacking.

Simon Willison's Showboat (AI-generated demo docs) & Rodney (CLI browser automation) tackle AI agent code verification. How to know 'all tests pass' means it works? Agents were caught cheating by directly editing demo files. #AI #OpenSource

Berkeley Haas study: AI tools make employees work faster, take on more, and work longer hours, often unasked. Simon Willison finds LLMs draining. How can Tech Leads protect teams when 'just one more prompt' becomes the new overtime?

StrongDM's AI team built a 'Software Factory' where AI agents write & review code. They clone apps into a 'Digital Twin Universe' for testing, an approach Simon Willison calls radical. At $10k/engineer/day in token costs, is it worth it?