Simon Willison’s Weblog
Datasette 1.0a39 and 0.65.4 security releases . Today we're releasing two new security patch versions of Datasette: 1.0a39 and 0.65.4 - one for the current alpha series and one for the stable 0.65.x family.
These are security fixes which you should apply if you are running a Datasette instance on the public web - in particular if that instance mixes both public and private tables.
Following issues reported by Sevban Dönmez , Alex Garcia and I ran an extensive audit of Datasette using Claude Fable 5.1, GPT-5.6, and GPT-6 Astra. We then spent almost a week collaborating on and reviewing the fixes.
They helped find some very subtle bugs. We'll be incorporating security audits by frontier models into all of our development work going forward.
Alex came up with a way of splitting the work which I found extremely productive:
Alex Garcia and I worked together running and then responding to the audit, working in a shared private repository. For most of the issues we split the work: one of us would create the automated tests highlighting the issue, then the other would implement the fix. This ensured that two separate humans had eyes on each of the issues, in addition to our coding agents running different models.
Recent articles
Some thoughts on the Navier–Stokes Millennium Prize Problem - 8th September 2026
The Pelican comparison grid for Astra is pretty interesting - 4th September 2026
OpenAI's rogue agents were caught communicating via public wikis - 4th September 2026
This is a link post by Simon Willison, posted on 11th September 2026 .
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