GitHub Shifts Git Infrastructure to Azure for Scalability

What happened

GitHub has migrated the majority of its Git repositories to Azure, with most repositories now having two of their five replicas in Azure. This shift is part of a broader effort to manage growing traffic and operational demands.

The migration started in August 2025, with the first copy of a repository being placed in Azure's Central US region. Azure currently serves about half of GitHub's Git traffic, indicating a significant shift in infrastructure strategy.

Why it matters

GitHub's Git operations are a Tier 0 service, meaning they are critical to the community and foundational to nearly everything on GitHub. Ensuring the reliability and performance of repository data is essential for maintaining service stability.

Key details

In internal testing, writes to different references saw 3–4x higher throughput at lower latency, showcasing the benefits of the new infrastructure. The data, services, and dependencies had to move first to ensure the Tier 0 service remained operational.

The migration was driven by the agentic shift, including rapidly growing traffic, a hard ceiling on data center power capacity, and physical supply chain constraints. This required a strategic reorganization of the infrastructure to maintain service reliability.