PostgreSQL is often chosen as the main database for modern applications, but many lessons only appear after a product is live. In this session, I will share what I learned using PostgreSQL while building and running real full-stack products. We will talk about schema design choices, performance surprises, migrations, and how database decisions affect application growth over time. I will also cover common mistakes developers make when they move fast and how PostgreSQL helps or sometimes challenges them. This session is focused on practical experience and real outcomes, not theory. Attendees will leave with a clearer idea of how to use PostgreSQL more confidently in production systems.