Simon Willison — Week of 2026-05-08 to 2026-05-15#

Highlight of the Week#

The standout development this week is Simon’s rapid adaptation to the latest frontier model capabilities, most notably releasing llm 0.32a2 to expose and visualize the new interleaved reasoning tokens of GPT-5 class models directly in the terminal. This perfectly pairs with his hands-on explorations of embedding LLM calls deeply into developer workflows, such as executing prompts via script shebangs and leveraging models to output rich HTML rather than just Markdown.

Simon Willison — Week of 2026-06-12 to 2026-06-18#

Highlight of the Week#

The most impactful release this week is the launch of datasette-apps, a major new plugin that allows developers to run self-contained, sandboxed HTML and JavaScript applications directly against a persistent Datasette backend. It brilliantly merges Simon’s ongoing experiments with AI-generated “vibe-coded” single-file tools and robust security architectures, pushing Datasette from a read-only publishing platform into a comprehensive ecosystem for building interfaces over data.

Simon Willison — Week of 2026-06-18 to 2026-06-25#

Highlight of the Week#

This week’s absolute standout is the launch of the datasette-apps plugin, which fundamentally transforms how we build micro-applications over local databases. By utilizing tightly constrained iframe sandboxes and Content-Security-Policy headers, developers and LLMs alike can safely run custom HTML/JS interfaces against a persistent Datasette backend. It brilliantly merges Simon’s ongoing experiments with AI-assisted “vibe coding” and robust security architectures into a core ecosystem feature, effectively bridging the gap between Claude Artifacts and secure data environments.

Simon Willison — 2026-05-10#

Highlight#

Simon highlights a stark example of AI hallucination making its way into mainstream journalism, serving as a critical warning for anyone relying on LLMs for factual summarization.

Posts#

Quoting New York Times Editors’ Note · Source Simon shares a sobering editors’ note from the New York Times illustrating the dangers of unchecked generative AI in the newsroom. A reporter mistakenly attributed an AI-generated summary of Canadian Conservative leader Pierre Poilievre’s views as a direct, verbatim quote. The hallucinated text falsely claimed he called politicians who changed allegiances “turncoats,” underscoring exactly why LLM outputs must be rigorously verified against primary sources rather than trusted blindly.

Simon Willison — 2026-06-14#

Highlight#

Today’s highlight is a thoughtful commentary on the ongoing debate around AI replacing software engineers. Drawing on an essay by Arvind Narayanan and Sayash Kapoor, Simon highlights why the real value of a developer lies in deep systemic understanding rather than just generating lines of code.

Posts#

Why AI hasn’t replaced software engineers, and won’t · Source Simon highlights an essay by Arvind Narayanan and Sayash Kappor that pushes back against the narrative of mass AI-driven layoffs in tech. They point to hard data—like zero New York WARN Act filings checking the newly added “AI” box over a full year—to demonstrate that developers are heavily cushioned from displacement. The authors argue that while AI accelerates the actual typing of code, the true bottlenecks of software engineering are specifying what to build, verifying the delivery, and applying deep context. Simon echoes this from his own workflow, noting that while LLMs help him decide and verify, his ultimate value remains anchored in his “deep human understanding” of both the underlying problems and the agent-built solutions.

Simon Willison — 2026-06-24#

Highlight#

Today’s most interesting post is Simon’s creation of browser-compat-db, demonstrating a clever mix of AI-assisted programming to convert Mozilla’s MDN compatibility data into a SQLite database, along with a neat CI/CD trick for hosting it. It perfectly encapsulates his workflow of using frontier models like Opus 4.8 and GPT-5.5 to rapidly build, deploy, and explore small, sharp data tools.

Posts#

simonw/browser-compat-db · Source Inspired by Mozilla’s new MDN Model Context Protocol (MCP) service, Simon used Claude Code for web (Opus 4.8) to write a script that converts the comprehensive browser compatibility repository into a ~66MB SQLite database. To bypass the fact that GitHub Releases do not provide open CORS headers, he utilized Codex Desktop (GPT-5.5) to build a GitHub Actions workflow that force-pushes the database to an “orphan” branch. This deployment strategy allows the database to be served via GitHub’s CDN with open CORS headers, enabling immediate exploration directly in the browser via Datasette Lite.

Simon Willison — 2026-06-28#

Highlight#

The standout thought today is a philosophical shift on AI-assisted programming via Jon Udell, challenging the phrase “human in the loop”. It’s a crucial perspective for developers—framing autonomous tools as “agents in our loop” rather than black boxes, ensuring we maintain our engineering authority.

Posts#

Quoting Jon Udell Simon highlights a thought-provoking quote from Jon Udell about how we frame AI-assisted development. Udell pushes back against the standard “human in the loop” terminology, arguing that it inherently surrenders authority to the machine. Instead, he advocates for an “agent in the loop” approach where developers maintain their standard workflows and simply invite agentic software in to assist. It is a necessary reminder to treat generative AI as a tool that serves the engineering team, rather than an unreviewable black box that just takes prompts and emits features.

Simon Willison — Week of 2026-06-25 to 2026-07-03#

Highlight of the Week#

The single most impactful release this week was Simon’s launch of llm-coding-agent 0.1a0, which successfully turns his popular llm library into a full-fledged coding agent capable of file manipulation and command execution. Bootstrapped entirely using Claude Fable 5 via test-driven development, this represents a massive leap forward for his CLI ecosystem and a brilliant showcase of using frontier models to build the very tools that will orchestrate them.