How a Frontier Model Gets Built, Read from the Kimi K3 Report

Building a frontier AI model like Kimi K3 involves far more than just the core architecture, as revealed in its unusually transparent technical report. The model's signature million-token context is enabled by a novel attention mechanism that uses a fixed-size summary instead of an ever-growing memory cache. This is combined with a massive 2.8-trillion-parameter Mixture-of-Experts design, which routes each token to a small fraction of specialized networks for efficiency