During July 2025, Dmitry Savelev developed a new billing metrics serialization system for the neondatabase/neon repository, focusing on standardizing event formats for cross-team data processing in S3. He migrated the storage format from JSON to NDJSON, introducing the serialize_in_chunks_ndjson function to efficiently handle large datasets and partitioning billing data files by hour to improve query performance and scalability. Working primarily in Python and Rust, Dmitry enhanced backend reliability by updating test coverage to validate NDJSON parsing. This work addressed the billing team’s requirements for a unified event format, supporting more robust metrics ingestion and downstream analytics workflows.