MMBU Challenge / Tracks 2 and 3 / engineering review, 22 Oct 2026

How we train, how we measure, and every decision in between.

A walkthrough for the MMBU organizers. It starts with the result at a glance, then opens each decision: the evaluation we trust, the reinforcement learning recipe, the fine-tuning we tried and dropped, the data, the failures, and what we have not tried yet. Every figure has its raw data one click away, and every term is clickable.