simonw/browser-compat-db
Inspired by Mozilla's new MDN MCP service, Simon Willison converted the mdn/browser-compat-data repository into a SQLite database. He used Claude Code for web (Opus 4.8) and sqlite-utils to generate the conversion script, and a GitHub Actions workflow to deploy the ~66MB database to GitHub CDN with open CORS headers, enabling direct download and exploration via Datasette Lite.
simonw/browser-compat-db
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24th June 2026 - Link Blog
simonw/browser-compat-db. Inspired by Mozilla's new MDN MCP service - source code here - I decided to try converting their comprehensive mdn/browser-compat-data repository full of browser compatibility data into a SQLite database.
This new GitHub Repo includes a Claude Code for web (Opus 4.8) generated script for doing that using sqlite-utils.
I wanted the resulting ~66MB SQLite database to be available via the GitHub CDN with open CORS headers. GitHub releases don't have those, but any file stored in a regular GitHub repository does - so I had Codex Desktop (GPT-5.5) build a GitHub Actions workflow that builds the database and then force-pushes it to a db "orphan" branch.
You can download the resulting database from here, and since it's hosted with open CORS headers you can also explore it with Datasette Lite.
Recent articles
Porting the Moebius 0.2B image inpainting model to run in the browser with Claude Code - 22nd June 2026
sqlite-utils 4.0rc1 adds migrations and nested transactions - 21st June 2026
Datasette Apps: Host custom HTML applications inside Datasette - 18th June 2026
This is a link post by Simon Willison, posted on 24th June 2026.
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