During February 2025, Davrene worked on the ssc-sp/datahub-portal repository, delivering a tenant-aware user existence validation feature for the login process. By introducing the IUserInformationService interface and its implementations, Davrene enabled cross-tenant checks to determine user existence by email, ensuring that login attempts are accurately scoped to the correct tenant. The backend logic, written in C#, was integrated with existing API endpoints to gracefully handle cases where a user is registered in the tenant but not yet present in the portal. This approach improved login accuracy and user experience, demonstrating solid backend development and API integration skills within a focused scope.