Developed HTTP Checksum Trait Support for REST protocols in the smithy-lang/smithy repository, enabling data integrity verification for restXml and restJson1 workflows. The work involved designing and implementing protocol extensions using Smithy and JSON, with careful attention to API design and protocol development best practices. The implementation preserved backward compatibility by aligning with existing REST protocol behaviors and included comprehensive changelog management to document the new feature. Version control practices ensured traceability through detailed commit references. This feature is production-ready, supporting broader adoption of HTTP-based data integrity checks in client and server REST interactions while maintaining robust documentation.