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 — 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.