Senior Backend Executive Interview Questions and Answers

Built a real-time chat application using Node.js with WebSockets for instant messaging.

• Utilized Socket.io library for real-time communication between clients and server

• Implemented a scalable architecture using microservices to handle different functionalities like user authentication, message storage, and message delivery

• Used MongoDB as the database to store chat messages and user information

• Implemented JWT tokens for secure user authentication and authorization

Asynchronous operations in Node.js are managed using callbacks, promises, async/await, and event emitters.

• Use callbacks to handle asynchronous operations in a sequential manner

• Utilize promises for cleaner and more readable asynchronous code

• Async/await provides a more synchronous way to write asynchronous code

• Event emitters can be used to handle multiple asynchronous operations simultaneously

I have extensive experience with AWS serverless architecture, including Lambda functions, API Gateway, and DynamoDB.

• Utilized Lambda functions to execute code without provisioning or managing servers

• Integrated API Gateway to create and deploy RESTful APIs

• Stored and retrieved data using DynamoDB for a scalable and high-performance database solution

Extensive experience with nodejs and AWS services

• Developed multiple backend applications using nodejs

• Implemented serverless architecture on AWS using Lambda functions

• Utilized AWS services like EC2, S3, RDS, and API Gateway

• Experience with deploying and managing applications on AWS

• Optimized performance and scalability of applications on AWS

Use Arrays.sort() method in Java to sort an array of strings.

• Import the Arrays class from java.util package.

• Use Arrays.sort() method to sort the array of strings.

• Example: String[] arr = {"banana", "apple", "orange"}; Arrays.sort(arr);