open_scion: Concurrent Work for Hundreds of Agents, Git Server Without Bottlenecks

Resolves traditional Git bottlenecks in environments where hundreds of coding agents simultaneously read and write code. It implements the design of Scion, developed internally by Anthropic, as open source, changing the workflow so that clients fetch and process only the necessary objects from the server instead of cloning the entire repository.

Instead of a merge queue, it applies changes immediately using a compare-and-swap mechanism, automatically resolving conflicts via LLMs or tools when they occur. All change history is recorded in a changeset log in the database for real-time tracking, and the server ensures scalability through a stateless architecture.

It handles large-scale traffic by combining SQLite or PostgreSQL with object storage such as S3 and GCS. It adopts a vendor-neutral architecture to integrate with various AI providers and supports per-agent permission management and semantic review rules.