Worked on the open-webui/open-webui repository to enhance AWS S3 integration by introducing configurable key prefix support for S3 storage operations. Refactored the S3StorageProvider in Python to ensure consistent application of key prefixes across uploads, downloads, and deletions, improving data organization and reliability. Addressed a bug related to S3 key path formatting by ensuring the correct insertion of the '/' character, which resolved file path issues during uploads. Focused on backend development, these changes streamlined storage management and reduced potential errors for developers interacting with S3. The work demonstrated attention to detail in both feature implementation and bug resolution.