Worked on enhancing the Nextcloud storage stack by implementing Server-Side Encryption with Customer-Provided Keys (SSE-C) for the Amazon S3 external storage backend in the nextcloud/server repository. This involved introducing a dedicated parameter for SSE-C encryption keys and integrating it into core storage operations, thereby improving data-at-rest security for external storage. Complementing the backend changes, updated the nextcloud/documentation repository to provide clear guidance for administrators on securely configuring and deploying the SSE-C feature. Utilized PHP for backend development, applied encryption techniques, and ensured comprehensive AWS S3 integration, resulting in more secure and auditable storage workflows for Nextcloud deployments.