Questions that have appeared at Visa for a Software Engineer (Technical) interview.

1. System Design

Question: Can you explain how you would design a scalable and efficient payment gateway?

Question: How would you approach designing a system for handling millions of transactions per second?

2. Database Management

Question: Could you explain the difference between SQL and NoSQL databases? When would you use one over the other?

Question: How would you design a database schema for an e-commerce platform?

3. Data Structures and Algorithms

Question: Can you describe a situation where you would use a hash table instead of an array?

Question: Can you explain the difference between a stack and a queue, and in what situations each would be preferable?

4. Software Development Methodologies

Question: Can you explain the Agile development process and how it differs from Waterfall?

Question: Describe a project where you used the Scrum framework. What was your role and how did it contribute to the project's success?

5. Networking and Security

Question: How would you ensure security in a cloud-based application?

Question: Could you explain how a secure transaction takes place over the internet?

6. Testing

Question: Can you describe the different types of software testing and when you would use each one?

Question: How would you go about testing a new feature before it's released to production?

7. Problem Solving

Question: Describe a technical problem you encountered in a project and how you resolved it.

Question: How would you troubleshoot a system if it started responding slowly?

8. Software Architecture

Question: Can you explain the concept of microservices and how they differ from monolithic architecture?

Question: What factors would you consider when choosing between a microservices and a monolithic architecture for a new project?

9. Operating Systems

Question: Can you explain the concept of multithreading and how it's handled in an operating system?

Question: What are the key differences between Linux and Windows operating systems?

10. Version Control

Question: Can you describe a situation where version control was critical to the success of a project?

Question: How have you used Git (or another version control system) in your previous projects?