Posted by Full-stack developers need expertise in both frontend and backend technologies, along with problem-solving and system design skills. If you’re preparing for a full-stack developer interview, here are the top 10 questions you should expect and tips on how to answer them.
1. What is the difference between frontend and backend development?
Answer:
Frontend development deals with the user interface and experience, including HTML, CSS, and JavaScript frameworks like React, Angular, or Vue.js. Backend development manages server-side logic, databases, and APIs, using technologies like Node.js, Python, Java, or PHP.
Tip: Provide real-world examples of how frontend and backend work together, such as handling a login request.
2. Explain how RESTful APIs work.
Answer:
RESTful APIs follow REST principles to enable communication between client and server over HTTP. They use standard methods like GET, POST, PUT, DELETE and return data in JSON or XML format.
Tip: Discuss how you’ve designed or consumed RESTful APIs in past projects.
3. What are the key differences between SQL and NoSQL databases?
Answer:
- SQL databases (MySQL, PostgreSQL) are structured, use tables, and are best for relational data.
- NoSQL databases (MongoDB, Cassandra) are schema-less and handle unstructured data efficiently.
Tip: Explain when to use SQL vs. NoSQL based on scalability and data requirements.
4. How does authentication and authorization work in a full-stack application?
Answer:
Authentication verifies who you are (e.g., login with a username/password), while authorization determines what you can do (e.g., access control based on user roles).
Common authentication methods include JWT (JSON Web Token), OAuth, and session-based authentication.
Tip: Mention any authentication libraries or tools you have used, such as Passport.js or Firebase Authentication.
5. What is the purpose of Docker and how does it help in development?
Answer:
Docker allows developers to containerize applications, making them portable and scalable across different environments. It ensures that code runs the same way in development, testing, and production.
Tip: Discuss how you’ve used Docker in projects for environment consistency and deployment.
6. What are WebSockets and how do they differ from HTTP?
Answer:
WebSockets enable real-time communication between the client and server by maintaining an open connection, unlike HTTP, which follows a request-response model.
Tip: Provide examples like chat applications or live stock updates.
7. How do you optimize website performance?
Answer:
- Frontend: Code splitting, lazy loading, image optimization, caching, and minifying CSS/JS.
- Backend: Query optimization, indexing, load balancing, and caching strategies like Redis.
Performance optimization techniques include:
Tip: Share a real-world case where you improved performance.
8. Explain microservices architecture and its advantages.
Answer:
Microservices break applications into smaller, independent services that communicate via APIs. Advantages include scalability, flexibility, and fault isolation.
Tip: Mention a project where you used or migrated to a microservices-based architecture.
9. What is CI/CD, and why is it important?
Answer:
CI/CD (Continuous Integration/Continuous Deployment) automates testing and deployment to improve development efficiency and reduce bugs in production.
Tip: Discuss tools like Jenkins, GitHub Actions, or GitLab CI/CD pipelines.
10. How do you handle state management in a React application?
Answer:
React state management options include:
- useState & useReducer for local state.
- Context API for global state.
- Redux/Zustand/Recoil for complex state management.
Tip: Explain why you chose a specific state management approach in a past project.
How TechHiringHub Can Help You Prepare?
TechHiringHub provides:
- Mock Interviews – Hands-on full-stack developer interview practice.
- Technical Resources – Guides on frontend and backend technologies.
- Job Listings – Find full-stack developer opportunities tailored to your skills.
- Community Support – Connect with recruiters and developers for interview insights.
Final Thoughts
Preparing for a full-stack developer interview requires mastering both frontend and backend technologies, along with problem-solving skills. By practicing common questions and using resources like TechHiringHub, you can improve your chances of landing your dream job.