Worked on the apache/nifi repository to enhance reliability, security, and data integrity across messaging and storage workflows. Developed a configurable delivery guarantee for PublishAMQP, surfacing broker-level failures and enabling at-least-once delivery to reduce silent data loss. Addressed a directory traversal vulnerability in DeleteSFTP by improving dot-path handling and adding regression tests. Improved S3 multipart upload correctness by isolating multipart state with FlowFile UUIDs, preventing data corruption during concurrent uploads. Utilized Java for backend development, message queuing, and AWS S3 integration, applying concurrency control, robust security checks, and comprehensive unit testing to ensure operational resilience and traceability.