simonw/browser-compat-db
📰 Simon Willison's Blog
Learn how to convert browser compatibility data into a SQLite database and make it available via GitHub CDN with open CORS headers
Action Steps
- Download the mdn/browser-compat-data repository
- Convert the data into a SQLite database using sqlite-utils and the provided build_db.py script
- Create a GitHub Actions workflow to build and deploy the database
- Host the database on a 'db' orphan branch with open CORS headers
- Explore the database using Datasette Lite
Who Needs to Know This
Developers and data engineers can benefit from this tutorial to create and share browser compatibility data in a scalable and accessible way
Key Insight
💡 Converting large datasets into SQLite databases can make them more accessible and scalable
Share This
📊 Convert browser compatibility data to a SQLite DB and share via GitHub CDN! 💻
Key Takeaways
Learn how to convert browser compatibility data into a SQLite database and make it available via GitHub CDN with open CORS headers
Full Article
Title: simonw/browser-compat-db
URL Source: https://simonwillison.net/2026/Jun/24/browser-compat-db/
Published Time: Thu, 25 Jun 2026 00:24:16 GMT
Markdown Content:
# [Simon Willison’s Weblog](https://simonwillison.net/)
[Subscribe](https://simonwillison.net/about/#subscribe)
**Sponsored by:** Microsoft — Agent projects stall between demo and production. Microsoft's MVP checklist closes that gap. [Try it](https://fandf.co/3POWawQ)
24th June 2026 - Link Blog
**[simonw/browser-compat-db](https://github.com/simonw/browser-compat-db)**. Inspired by Mozilla's [new MDN MCP service](https://developer.mozilla.org/en-US/blog/introducing-mdn-mcp-server/) - [source code here](https://github.com/mdn/mcp) - I decided to try converting their comprehensive [mdn/browser-compat-data](https://github.com/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](https://github.com/simonw/browser-compat-db/blob/main/build_db.py) for doing that using [sqlite-utils](https://github.com/simonw/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](https://github.com/simonw/browser-compat-db/blob/main/.github/workflows/build-db.yml) that builds the database and then force-pushes it to a `db` "orphan" branch.
You can download the resulting database [from here](https://github.com/simonw/browser-compat-db/blob/db/browser-compat.db), and since it's hosted with open CORS headers you can also [explore it with Datasette Lite](https://lite.datasette.io/?url=https://github.com/simonw/browser-compat-db/blob/db/browser-compat.db#/browser-compat/releases_tree).
Posted [24th June 2026](https://simonwillison.net/2026/Jun/24/) at 11:59 pm
## Recent articles
* [Porting the Moebius 0.2B image inpainting model to run in the browser with Claude Code](https://simonwillison.net/2026/Jun/22/porting-moebius/) - 22nd June 2026
* [sqlite-utils 4.0rc1 adds migrations and nested transactions](https://simonwillison.net/2026/Jun/21/sqlite-utils-40rc1/) - 21st June 2026
* [Datasette Apps: Host custom HTML applications inside Datasette](https://simonwillison.net/2026/Jun/18/datasette-apps/) - 18th June 2026
This is a **link post** by Simon Willison, posted on [24th June 2026](https://simonwillison.net/2026/Jun/24/).
[github 188](https://simonwillison.net/tags/github/)[mozilla 117](https://simonwillison.net/tags/mozilla/)[projects 540](https://simonwillison.net/tags/projects/)[github-actions 67](https://simonwillison.net/tags/github-actions/)[datasette-lite 23](https://simonwillison.net/tags/datasette-lite/)[ai-assisted-programming 391](https://simonwillison.net/tags/ai-assisted-programming/)[model-context-protocol 28](https://simonwillison.net/tags/model-context-protocol/)[mdn 4](https://simonwillison.net/tags/mdn/)
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URL Source: https://simonwillison.net/2026/Jun/24/browser-compat-db/
Published Time: Thu, 25 Jun 2026 00:24:16 GMT
Markdown Content:
# [Simon Willison’s Weblog](https://simonwillison.net/)
[Subscribe](https://simonwillison.net/about/#subscribe)
**Sponsored by:** Microsoft — Agent projects stall between demo and production. Microsoft's MVP checklist closes that gap. [Try it](https://fandf.co/3POWawQ)
24th June 2026 - Link Blog
**[simonw/browser-compat-db](https://github.com/simonw/browser-compat-db)**. Inspired by Mozilla's [new MDN MCP service](https://developer.mozilla.org/en-US/blog/introducing-mdn-mcp-server/) - [source code here](https://github.com/mdn/mcp) - I decided to try converting their comprehensive [mdn/browser-compat-data](https://github.com/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](https://github.com/simonw/browser-compat-db/blob/main/build_db.py) for doing that using [sqlite-utils](https://github.com/simonw/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](https://github.com/simonw/browser-compat-db/blob/main/.github/workflows/build-db.yml) that builds the database and then force-pushes it to a `db` "orphan" branch.
You can download the resulting database [from here](https://github.com/simonw/browser-compat-db/blob/db/browser-compat.db), and since it's hosted with open CORS headers you can also [explore it with Datasette Lite](https://lite.datasette.io/?url=https://github.com/simonw/browser-compat-db/blob/db/browser-compat.db#/browser-compat/releases_tree).
Posted [24th June 2026](https://simonwillison.net/2026/Jun/24/) at 11:59 pm
## Recent articles
* [Porting the Moebius 0.2B image inpainting model to run in the browser with Claude Code](https://simonwillison.net/2026/Jun/22/porting-moebius/) - 22nd June 2026
* [sqlite-utils 4.0rc1 adds migrations and nested transactions](https://simonwillison.net/2026/Jun/21/sqlite-utils-40rc1/) - 21st June 2026
* [Datasette Apps: Host custom HTML applications inside Datasette](https://simonwillison.net/2026/Jun/18/datasette-apps/) - 18th June 2026
This is a **link post** by Simon Willison, posted on [24th June 2026](https://simonwillison.net/2026/Jun/24/).
[github 188](https://simonwillison.net/tags/github/)[mozilla 117](https://simonwillison.net/tags/mozilla/)[projects 540](https://simonwillison.net/tags/projects/)[github-actions 67](https://simonwillison.net/tags/github-actions/)[datasette-lite 23](https://simonwillison.net/tags/datasette-lite/)[ai-assisted-programming 391](https://simonwillison.net/tags/ai-assisted-programming/)[model-context-protocol 28](https://simonwillison.net/tags/model-context-protocol/)[mdn 4](https://simonwillison.net/tags/mdn/)
### Monthly briefing
Sponsor me for **$10/month** and get a curated email digest of the month's most important LLM developments.
Pay me to send you less!
[Sponsor & subscribe](https://github.com/sponsors/simonw/)
* [Disclosures](https://simonwillison.net/about/#disclosures)
* [Colophon](https://simonwillison.net/about/#about-site)
* ©
* [2002](https://simonwillison.net/2002/)
* [2003](https://simonwillison.net/2003/)
* [2004](https://simonwillison.net/2004/)
* [2005](https://simonwillison.net/2005/)
* [2006](https://simonwillison.net/2006/)
* [2007](https://simonwillison.net/2007/)
* [2008](https://simonwillison.net/2008/)
* [2009](https://simonwillison.net/2009/)
* [2010](https://simonwillison.net/2010/)
* [2011](https://simonwillison.net/2011/)
* [2012](https://simonwillison.net/2012/)
* [2013](https://simonwillison.net/2013/)
* [2014](https://simonwillison.net/2014/)
* [2015
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