Abstract

Online banking has become an indispensable part of the modern financial ecosystem, necessitating systems that are not only
highly functional but also rigorously secure and scalable. This paper presents a robust backend solution designed using Java
Full Stack technologies, specifically the Spring Boot Framework, to replace traditional, monolithic banking software with a
lightweight, decoupled RESTful architecture. The proposed system addresses critical security vulnerabilities inherent in legacy
architectures by implementing Stateless Authentication using JSON Web Tokens (JWT) and Spring Security, effectively
mitigating risks associated with Cross-Site Request Forgery (CSRF) and session-based attacks. Data integrity is mathematically
guaranteed through ACID-compliant transaction management using the @Transactional architecture, ensuring that fund
transfers are processed reliably without data loss during network failures. Furthermore, the application utilizes Spring Data JPA
for efficient interaction with a MySQL database, providing built-in protection against SQL injection. This research demonstrates
a production-ready approach to building secure financial applications, prioritizing modularity, maintainability, and advanced
cryptographic data protection.