The interview revolved around two panelists, and I was referred through a recruiting agency. It primarily focused on core concepts of OOP, system design, microservices, and database design. Additional discussions included SOLID principles, design patterns, C#/.NET fundamentals, REST APIs, dependency injection, asynchronous programming, SQL query optimization, indexing, Entity Framework, event-driven architecture, message queues, caching strategies, cloud concepts, scalability, performance optimization, CI/CD practices, and real-world problem-solving scenarios based on previous project experience. The interviewers were interested in both theoretical understanding and practical application of these concepts in production environments.