Worked on the microsoft/teams.ts repository to address a critical issue affecting message extension rendering in Microsoft Teams. Focused on API development and bug fixing using TypeScript, the developer identified and corrected the AttachmentLayout type by replacing 'carousel' with 'grid'. This targeted change resolved a bug that previously prevented responses from being displayed in Teams message extensions, thereby improving reliability for both users and extension developers. The solution was delivered through a single, auditable commit, demonstrating a precise and efficient approach to code maintenance. The work reflects a strong understanding of TypeScript and the intricacies of Teams API integration.