Contributed to the apache/iceberg repository by enhancing schema evolution safety and code clarity over a two-month period. Delivered a targeted feature by annotating the SchemaUpdate constructor with @VisibleForTesting, clarifying its intended use for testing and improving maintainability for Java developers. Addressed a critical schema evolution edge case by implementing a guardrail that prevents deletion of a map value type, backed by a regression test to enforce data integrity. Focused on low-risk, well-documented changes, leveraging skills in Java, code annotations, and unit testing to support stability and onboarding for contributors working with Iceberg’s evolving data model.