Anthropic Replaces Git with Its In-House Source Control System Scion
Understand the story
On October 14, 2026, Simon Willison wrote about Anthropic's introduction of its in-house source code control system, Scion. Anthropic replaced Git with Scion to manage its source code. According to the report, its main branch history is nearly 100 GB, with about 25 million code checkouts per day. The migration was completed by a 7-person team over 5 months.
AI overview of reporting · Updated 4 days ago
Reporting timeline
Explore different aspects of the story through its reporting.
- Simon WillisonRedesigning source control at Anthropic
Simon Willison relays Anthropic's writeup on its in-house source control system Scion, built to replace Git, with nearly 100 GB of main branch history and about 25 million code checkouts per day; a 7-person team completed the migration in 5 months.
Story heat trend
Current heat3·Comparable peak10（10/14 08:00）·Comparable change over 24 hours -50%
The trend compares the same continuously observed sources, which may cover fewer sources than the current heat score. Hover or select the chart to inspect each hour; use the left and right arrow keys to navigate.