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[ARTICLE · art-36889] src=simonwillison.net ↗ pub= topic=developer-tools verified=true sentiment=· neutral

OPFS + Pyodide test harness

Simon Willison built a test harness combining OPFS and Pyodide to explore whether Datasette Lite can edit persistent SQLite files stored in the browser's Origin Private File System. The tool allows testing this capability across different browsers.

read1 min views5 publishedJun 23, 2026

Tool: OPFS + Pyodide test harness I've been pondering if Datasette Lite - the Python Datasette application run entirely in the browser using Pyodide and WebAssembly - might be able to edit persistent SQLite files stored on the user's computer.

That's what OFPS (Origin Private File System) is for, so I had Claude Code for web build me this playground UI to try it out in different browsers.

Tags: browsers, pyodide, datasette-lite

source & further reading
simonwillison.net — original article simonw/browser-compat-db Quoting Tom MacWright Prompt Injection as Role Confusion
── more in #developer-tools 4 stories · sorted by recency
── more on @datasette lite 3 stories trending now
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