How the Claude Code team reviews 30,000 changes a day
Anthropic's Claude Code team describes its internal review pipeline, built for a repo where daily merged changes went from ~2,500 in May to over 30,000 in September. Review is split into six layers: runnable verification and a fresh-context subagent before the PR exists; a Claude reviewer on every PR that reads the diff against the whole repo and the stated intent, with findings voted on by several agents before posting; a security review that can block merge; CI; risk-tiered human approval (0/1/2 people) assigned by a classifier reading the change rather than the author; then merge queue, flags, internal dogfooding and one-step rollback. They also document the failure modes: one CLI PR ran more than fifty review rounds overnight, and git blame showed ~59% of flagged lines predated the reviewer's first pass, prompting a three-round cap and diff-only re-review. Useful for teams wiring agents into their own review flow.