Worked on backend and stability improvements across apache/iceberg and apache/parquet-java repositories, focusing on Java-based solutions for build quality, error handling, and data compression. In apache/iceberg, aligned build scripts with Gradle 7 standards, refactored ThreadLocal usage for safer memory management, and enhanced JdbcLockFactory to support retryable transient database failures, all supported by expanded unit testing and documentation updates. In apache/parquet-java, addressed a regression in LZ4_RAW heap decompression by restructuring stream handling and implemented overflow protection in CapacityByteArrayOutputStream. These contributions improved maintainability, resilience, and correctness, leveraging skills in Java, database management, and robust unit testing practices.