I recently attended a TCS interview for a Java Full Stack role. The interview was mainly focused on practical project experience rather than just theoretical knowledge. The interviewer started by asking me to explain my current project in detail. They expected a complete walkthrough of the project architecture, including the overall design, microservices communication, database interactions, authentication flow, deployment approach, and the technologies used. Be prepared to explain every component of your project and justify your design decisions. The technical discussion covered the following areas: Java: Core Java concepts, collections, multithreading, exception handling, and OOP principles. Java Streams: Questions on filtering, mapping, grouping, sorting, reducing, and solving practical stream-based coding scenarios. Spring & Spring Boot: Dependency Injection, Spring Boot annotations, Spring Data JPA, Spring Security, REST APIs, exception handling, and microservices concepts. REST APIs: They asked about HTTP methods, status codes, designing RESTful APIs, API versioning, and handling validations and exceptions. SQL: Multiple SQL queries involving joins, group by, aggregate functions, subqueries, and query optimization. CI/CD Pipeline: Questions on Git, branching strategy, build process, deployment pipeline, GitHub Actions/Jenkins, and how code moves from development to production. Overall, the interview was highly project-oriented. If you mention any technology in your resume, make sure you can confidently answer in-depth questions about it. Having hands-on knowledge of your project architecture and implementation details is more important than memorizing definitions. Preparation Tips: Revise your current project architecture thoroughly. Practice Java Stream API problems. Be strong in SQL joins and query writing. Review Spring Boot, REST APIs, and microservices concepts. Understand your CI/CD pipeline and deployment process. Be ready to explain real-time scenarios and design decisions from your project. Overall difficulty: 7.5/10. Candidates with solid hands-on project experience and a good understanding of Java Full Stack concepts should be able to perform well.