Redesigning source control at Anthropic anthropic.com

Anthropic says it built Scion, an in-house version control system, and migrated its monorepo from Git in five months as daily merged changes rose from about 2,500 in May 2026 to more than 30,000 in September. The company says Scion’s server-based, horizontally scalable design cut infrastructure CPU and memory needs 200-fold and made CI and research checkouts up to 100 times faster; a seven-person team also built its code-review tool, Antique.