Anthropic describes Scion, the in-house version control system it moved to from git

In an engineering post dated October 19, 2026, Anthropic says merges to its monorepo grew from about 2,500 to more than 30,000 a day, making source control the biggest development bottleneck. It says its team built Scion, an in-house version control system designed for always-online agents, and migrated off git in five months.

The same title also appears on Anthropic's research page with a date of October 13 and the same five-month claim. Everything above is Anthropic's own account.