WriterUS

Simon Willison

Creator of Datasette; independent writer

Security & sandboxes Tutorials & getting started Codex & OpenAI agents

Independent open-source developer, co-creator of Django and creator of Datasette. He writes a widely read blog on LLMs, including a guide to agentic engineering patterns, prompt injection and the "lethal trifecta".

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Videos (4)

Simon Willison · May 21, 2026

Datasette Agent - an AI assistant for Datasette to help explore and analyze data in SQLite.

Tutorials & getting started

Simon Willison · Jan 23, 2026

FastRender with Wilson Lin - building a web browser with swarms of thousands of coding agents

Multi-agent orchestration · Talks & interviews

Simon Willison · Nov 9, 2025

Reverse engineering Codex CLI to get GPT-5-Codex-Mini to draw me a pelican

Codex & OpenAI agents

Simon Willison · Nov 6, 2025

My process for upgrading Datasette plugins with uv and OpenAI Codex CLI

Codex & OpenAI agents · Tutorials & getting started

On X

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Jul 28, 2026
This is detailed, fascinating and answers all sorts of open questions

I'd love to know more about the "unsecured public code-evaluation sandbox hosted on a third-party provider's infrastructure" that the agent used to stage its attack against HF after it broke out of OpenAI https://t.co/9szwJc8vF5
Open on X

Quoted in the State of Harness report

“Run unattended coding agents in a container, VM or OS sandbox.”
Quoted in State of Harness — October 2026: What people are saying: X and Substack define the harness, Reddit counts the cost, Hacker News argues about trust · original

Sources

Verified Oct 29, 2026