Research note
Research note: Anthropic says it replaced Git with its own source control system, Scion, after daily merges passed 30,000
How we checked what Anthropic said about Scion, whether it is open source, and the credit criticism from a Mononoke developer.
What we set out to check
What Scion is, why Anthropic built it, whether it has been released, and what the criticism says.
What we found
- Anthropic’s post gives the merge growth, repository size, checkout volume and the 200x claim.
- The post does not release code or a licence, and gives no repository link.
- The Mononoke developer’s post sets out the similarities and asks for credit, not removal.
Numbers that differ
AI Weekly’s summary said Anthropic open-sourced Scion. Anthropic’s post does not say that, so we state that Scion is internal.
Labels we chose and why
- Confirmed for the migration and for Scion being internal, from Anthropic’s post.
- Company claim for Anthropic’s performance and growth figures.
- Confirmed for what the critic said, from their own post; their argument itself is their view.
What we could not verify
- Anthropic’s internal measurements.
- Any Anthropic response to the criticism.
What we searched
- Anthropic Scion source control
- Anthropic redesigning source control 30,000 merges
- Scion Mononoke credit
Every source we read
| Source | Used? | Why |
|---|---|---|
| Anthropic Engineering | USED | Primary source for all of Anthropic’s figures; says nothing about open-sourcing. |
| sunshowers | USED | The critic’s own post, dated 14 October. |
| AI Weekly | USED | Coverage of the post; its summary said Scion was open-sourced, which Anthropic’s post does not support. |
| Reddit r/AgentsOfAI | NOT USED | Discussion only. |