At Anthropic, coding is no longer the bottleneck to building systems or doing research. Claude can autonomously iterate on research loops, micro-optimize complex programs, and build new services from the ground up at a speed and scale the company has not seen before. The bottleneck now lies in developer infrastructure built for human scale: source control, builds, and CI.
In May 2026, Anthropic averaged around 2,500 code changes merged per day. By September, it merged over 30,000 per day. The company does not expect this growth to slow, since the demand for merging code is practically infinite and every bottleneck removed leads to more code produced.
To support this growth, Anthropic built Scion, an in-house version control system, and fully migrated its monorepo from git in five months. The company also built a code review surface called Antique, code search, a source control IAM system, and new ways of landing large amounts of reviewed code.
The monorepo has outgrown git's decentralized design. Its main branch history is almost 100 GB, and a compressed working copy exceeds 25 GB. Anthropic performs roughly 25 million code checkouts per day for CI. Git workarounds such as shallow clones, sparse checkouts, internal mirrors, and blob-stored seeds helped, but several hundred mirrors became hard to operate as the merge rate rose. Anthropic realized that because nearly all its clients are always-online agents, git's offline-first properties were undermining scale.
Source: Hacker News · Summarized by HeadlinesBriefing