Worked on the apache/pulsar repository to enhance reliability and data integrity in distributed messaging systems. Addressed a critical issue by ensuring that eventTime is consistently preserved when messages are redelivered or routed through retry topics and Dead Letter Queues, preventing timestamp drift and reducing the risk of processing errors. Implemented comprehensive test coverage to verify event timestamp preservation across all message lifecycle stages, strengthening guarantees for downstream consumers and auditing. Utilized Java and testing frameworks to deliver this bug fix, demonstrating a strong understanding of messaging system semantics and the complexities of event lifecycle management in distributed environments.