Architect Data ModelDesigned the data model for User, Business, Payment entities and their relationships in PostgreSQL. Collaborated with a team of 5 product owners to define data model requirements and created an entity-relationship model for more than 10 tables.Notification SystemUsing Webhooks and Message Broken to notify users the status of payment.I implemented a retry system orchestrated by the database scheduler using exponential backoff. Notifications are sent through Apache Active MQ as a message broker.Implement Java LibraryDeveloped a new library to encode and decode messages between payment terminals and banks, replacing a licensed software and saving over 100,000 MXN (5,400 USD) in two years. Ensured parity between the old and new library through unit testing.