Simon Willison’s Weblog

On Being A Senior Engineer. Thoughts on characteristics of a mature engineer from John Allspaw back in 2012. So much good thinking in here—my favourite piece of writing on the subject.

Posted 5th November 2017 at 6:16 am

Recent articles

What happens if AI labs train for pelicans riding bicycles? - 13th November 2025
Reverse engineering Codex CLI to get GPT-5-Codex-Mini to draw me a pelican - 9th November 2025
Video + notes on upgrading a Datasette plugin for the latest 1.0 alpha, with help from uv and OpenAI Codex CLI - 6th November 2025

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