Simon Willison’s Weblog

Understanding a Protocol. Andrew’s latest notes on how ActivityPub and Mastodon work under the hood, based on his extensive development work building out Takahē.

Posted 6th December 2022 at 12:50 am

Recent articles

OpenAI DevDay 2025 live blog - 6th October 2025
Embracing the parallel coding agent lifestyle - 5th October 2025
Designing agentic loops - 30th September 2025

andrew-godwin 19 mastodon 35 activitypub 10

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