Simon Willison’s Weblog

Reducing search indexing latency to one second. Really detailed dive into the nuts and bolts of Twitter’s latest iteration of search indexing technology, including a great explanation of skip lists.

Posted 26th June 2020 at 5:06 pm

Recent articles

GPT-5: Key characteristics, pricing and model card - 7th August 2025
OpenAI's new open weight (Apache 2) models are really good - 5th August 2025
ChatGPT agent's user-agent - 4th August 2025

data-structures 5 lucene 12 scaling 143 search 91 twitter 160

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