Fortifying Transactional Integrity: A Full-Stack Guide to Preventing Double Submissions and Race Conditions with Python & React

In the world of web applications, especially those handling financial transactions or critical user actions, data integrity is paramount. A seemingly innocuous double-click on a 'Submit' button can cascade into a series of unintended consequences: duplicate orders, double charges, or corrupted state. While a quick UI fix might seem sufficient, it only addresses the tip of the iceberg. The more insidious threat lies hidden in the backend: the race condition, where concurrent requests clash in a battle to modify the same resource, leading to unpredictable and often disastrous outcomes. This article tackles this two-headed problem from a full-stack perspective. We'll explore how to build a robust defense, starting with a user-friendly guard on the frontend using React and TypeScript. Then, we'll dive deep into the backend, implementing a powerful database-level locking mechanism in Python with Django and PostgreSQL to ensure transactional atomicity. By fortifying both the client and serve