Anthropic Cracks Code for Explosive Growth with Custom Version Control

The Surge

Anthropic's engineers are shipping code at a pace that broke their own plumbing. The company says daily code merges climbed from approximately 2,500 in May 2026 to over 30,000 by September 2026. That is a tenfold increase in roughly four months.

The Driver

The driver is Claude Code, Anthropic's agentic coding tool. Earlier 2026 reports indicated that Claude was writing more than 80% of Anthropic's merged production code. Before February 2025, that share reportedly sat in the single digits.

The Solution

Anthropic laid out the switch in a detailed engineering blog post published on October 13, 2026. The numbers behind the surge

The Numbers

The driver is Claude Code, Anthropic's agentic coding tool. Earlier 2026 reports indicated that Claude was writing more than 80% of Anthropic's merged production code. Before February 2025, that share reportedly sat in the single digits. Advertisement

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The Impact

Engineers were merging about 8x more code each day compared with their pre-2025 baselines. Claude also autonomously handled maintenance routines, generating 388 pull requests, with roughly 46% of them merged after human review.

The Future

Anthropic sells Claude Code to outside developers, and running the company's own engineering on it serves as a large internal stress test. A lab that can show its tool driving a tenfold jump in merges, and then document the infrastructure needed to absorb it, has a compelling pitch for enterprise buyers.

The Market Implications

Anthropic chose to build Scion rather than stretch Git further. If other AI-heavy engineering teams hit similar walls, the market for version control and CI tooling could face its biggest rethink in years.