Aleksandro Dokic enhanced the happy-geeks/wiser repository by focusing on data integrity and API reliability within Product Data Management. He replaced MySQL NOW() with C#’s DateTime.Now to standardize time handling and migrated cooldown and date values to parameterized SQL queries, reducing the risk of SQL injection. Aleksandro also fixed a product refresh calculation bug, updating both the underlying logic and the API release notes to ensure clarity for clients. His work demonstrated proficiency in C#, SQL, and backend development, resulting in safer data operations and more predictable API behavior. The changes reflect careful attention to security and maintainability.