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Anthropic builds Scion as code changes grow from 2,500 to 30,000 per day

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Anthropic describes Scion, a custom source-control system, and Antique, its code-review system, after daily merged changes rose from about 2,500 to more than 30,000. The architecture and trade-offs are relevant to teams adapting source control and review for much higher coding throughput.

What

Scion is Anthropic's custom alternative to Git, built as code changes grew sharply.

How

Anthropic reported more than 30,000 code changes merged per day in September, up from around 2,500 per day in May.

Why it matters

Scion was built by seven people and migrated from Git in five months, addressing source-control demands from CI, developer environments, and agent sandboxes.

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