Building Bluesky: a Distributed Social Network (Real-World Engineering Challenges)

Bluesky is a decentralized social network that allows users to own their data and services. It has experienced rapid growth and has implemented unique engineering solutions. The architecture has evolved from a v1 architecture that was not scalable or federated to a v2 architecture that is scalable and federated. Bluesky faced scaling issues with PostgreSQL and migrated to ScyllaDB. The infrastructure was initially hosted on AWS but was later moved to on-prem for cost and performance reasons. Building a social network comes with typical firefighting issues and outages are not life-or-death crises. Bluesky actively responds to user feedback and focuses on real-time support. Decentralized social networks offer advantages such as data ownership and customizability.