Marta Lakova explains StellarCore's architecture, covering the consensus protocol, ledger state management, and how data flows across the Stellar network. The presentation details how StellarCore maintains distributed agreement on transactions, closes ledgers every five seconds with finality, and enables new nodes to catch up via history archives.
Marta Lakova, a StellarCore engineer, provides a technical deep dive into StellarCore, the backbone of the Stellar network. She covers the high-level design including three core components: the transaction protocol (handling payments and assets), the Stellar consensus protocol (enabling distributed agreement), and the overlay protocol (enabling core-to-core communication). The presentation explains how StellarCore maintains ledger state through SQL databases and bucket snapshots, closes ledgers every five seconds with guaranteed finality, and tolerates up to F failures in a network of 3F+1 nodes. She details how transactions flow through the network, how Horizon indexes historical data, and how new nodes join by downloading state from history archives and replaying transactions. The design prioritizes safety over liveness, ensuring all cores produce identical results rather than optimistically producing blocks that could be rolled back.