Simon Willison’s Weblog

Timing and Synchronization in JavaScript. Comprehensive overview of how browsers (Opera in particular) load scripts and queue events, with suggestions for best practices.

Posted 30th April 2007 at 2:24 pm

Recent articles

First impressions of Claude Cowork, Anthropic's general agent - 12th January 2026
My answers to the questions I posed about porting open source code with LLMs - 11th January 2026
Fly's new Sprites.dev addresses both developer sandboxes and API sandboxes at the same time - 9th January 2026

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