Many developers focus on optimizing code but overlook a powerful lever for performance: database configuration tuning. In this talk, we explore the real-world impact of MySQL tuning using open source applications like Drupal Commerce and Laravel-based e-commerce platforms. Through a series of tests using JMeter and AWS, we measured latency, CPU usage, and queries per second before and after tuning. The results? Up to 63% reduced latency and improved system efficiency - even without changing a single line of application code. Learn how thoughtful MySQL tuning can deliver big performance wins and why it deserves a place in your development workflow.