Worked on the Consensys/teku repository to deliver two targeted API enhancements focused on improving client interoperability and data access efficiency. Developed a new RESTful endpoint for retrieving payload attestations directly from the operations pool, reducing the need for additional client-side logic. Enhanced the existing beacon block retrieval API to support both JSON and SSZ formats, introducing a header to streamline client-side deserialization. All changes were aligned with the beacon-APIs specification to ensure compatibility and standards compliance. Utilized Java and JSON extensively, applying backend development and API design skills to reinforce the reliability and usability of the beacon data plane.