Implement, document, and review an Account Balance REST API with clear architecture. Simulation Details: Regis is a leading technology company focused on building enterprise-grade banking platforms for financial institutions. Its flagship product, the Regis Banking Suite, delivers real-time account management, secure transaction processing, and seamless integration with third-party services. The platform leverages Java Spring Boot for backend microservices, Kubernetes for scalability, and PostgreSQL for high-performance data handling, all while meeting strict regulatory standards like PSD2 and GDPR. Regis partners with major European banks to co-develop advanced features such as fraud detection and AI-driven insights. Internally, the company fosters a culture of mentorship and continuous learning, with regular architecture reviews and workshops led by senior technical leaders. Regis is committed to balancing rapid delivery with uncompromising quality and compliance. You take on the role of a Backend Java Developer at Regis, collaborating directly with the Senior Backend Architect. Your mission is to implement a critical REST API endpoint for account balance retrieval, essential for the upcoming launch of Regis’ new banking platform. You are expected to demonstrate both technical competence and strategic thinking, balancing practical coding with a vision for scalable enterprise solutions. - Engage in a detailed chat with the Senior Backend Architect to clarify requirements and confirm your understanding. - Write and refine a single Java file for the REST API endpoint, focusing on validation, error handling, logging, and documentation. - Participate in a voice review to discuss your implementation and propose architectural improvements. - Demonstrate your skills in Java Spring Boot and technical problem-solving by delivering a robust, production-ready solution and articulating how it could be scaled and improved.