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Zeitgeist — a spike by Chris Gathercole
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  2. Simon Willison — Creator of Datasette; co-creator of Django/

Redesigning source control at Anthropic

Blog · Watch/Read · (gathered 2026-10-14)

  • Anthropic built a custom, centralized source control system called Scion (and code review system Antique) to manage an extreme 12x surge in daily code merges (from 2,500 to 30,000 in six months), likely driven by their rapidly evolving Fable/Mythos class AI models.
  • Scion was designed to handle requirements like a 100 GB main branch history and 25 million daily CI checkouts (which would be 600 PB of Git traffic), and was built by a team of seven in five months.
  • The system’s design, which Simon notes sounds like a reinvention of centralized source control akin to Subversion, omits offline support because its heaviest user, Claude, is necessarily online.
  • The piece also highlights Anthropic’s extensive use of “adversarial review” with AI, noting that skilled engineers are needed to steer models away from over-engineering in response to hypothetical concerns.