Simon Willison’s Weblog

Could Rails have been built without Ruby? Fascinating essay about how Ruby, like Lisp, lets you build new languages.

Posted 15th April 2005 at 5:42 pm

Recent articles

OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI - 12th December 2025
GPT-5.2 - 11th December 2025
Useful patterns for building HTML tools - 10th December 2025

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