Worked on the httpwg/http-extensions repository to enhance resiliency and security for resumable uploads, focusing on robust API design and clear technical documentation. Addressed Time-of-Check to Time-of-Use vulnerabilities by implementing revalidation measures and limiting concurrent uploads to mitigate abuse, using Markdown for documentation updates. Updated upload limits policy to prevent disruption of ongoing transfers while allowing flexibility, and clarified server behavior for handling upload length, partial content, and offsets. Fixed edge-case bugs and improved interoperability by ensuring invalid offsets result in upload failure. Combined security best practices with technical writing to deliver maintainable, developer-friendly improvements over the course of one month.