During October 2025, Brynjar focused on enhancing the reliability of the duckdb/duckdb-httpfs repository by addressing a critical bug in the S3 COPY workflow. He corrected the handling of FILE_SIZE_BYTES to ensure accurate CSV file size reporting, which is essential for trustworthy ETL processes and downstream analytics. Working primarily with C++ and SQL, Brynjar improved test coverage and adjusted SQL-based tests to properly count CSV files in S3, reducing the risk of incorrect file-size accounting. His backend development and database management skills contributed to more dependable S3-backed data ingestion, emphasizing correctness and robustness over new feature development during this period.