How Anthropic Built Scion for Agent-Scale Source Control

Published 16 October 2026

Anthropic migrated its 100GB-plus monorepo from Git to Scion in five months as daily merges grew from 2,500 to more than 30,000. The in-house system uses server-side operations, sparse and virtualized checkouts, and horizontally scalable caches to make CI and research checkouts up to 100 times faster.