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

Fly's new Sprites.dev addresses both developer sandboxes and API sandboxes at the same time - 9th January 2026
LLM predictions for 2026, shared with Oxide and Friends - 8th January 2026
Introducing gisthost.github.io - 1st January 2026

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