RapiPay Node JS Developer Interview Questions and Answers

Basic puzzles of medium complexity level. No improvement required

DSA questions of easy level. Asked for memory optimisations.

Q1. High level system design of wallet payment system, took example of paytm. This was hld questions so just basic components
Add your answer

Q1. Low level system design of parking lot system
Ans. 
Design a parking lot system at a low level
• Divide system into components like parking spots, ticketing system, payment system

• Implement data structures like queues for managing parking spots

• Use algorithms like least recently used for spot allocation

• Consider scalability and performance in design
Answered by AI
Add your answer
Q2. Review of one of my projects at past company
Add your answer

Q1. What is collection framework?
Ans. 
Collection framework is a unified architecture for representing and manipulating collections of objects in Java.
• It provides interfaces (like List, Set, Map) and classes (like ArrayList, HashSet, HashMap) to store and manipulate groups of objects.

• It allows for easy manipulation, sorting, searching, and iteration of collections.

• Collections in the framework can store objects of any type, including user-defined classes.

• Exa...read more
Answered by AI
Add your answer
Q2. What is spring boot dependency injection?
Ans. 
Spring Boot dependency injection is a design pattern where objects are passed their dependencies rather than creating them internally.
• In Spring Boot, dependency injection is achieved through the use of @Autowired annotation.

• It helps in achieving loose coupling between classes and promotes easier testing and maintenance.

• Example: @Autowired private UserService userService; // Injecting UserService dependency
Answered by AI
Add your answer
Q3. What is the use of rate limiter?
Ans. 
Rate limiter is used to control the rate of incoming requests to a server or API.
• Prevents server overload by limiting the number of requests a client can make in a specific time period

• Helps protect against DDoS attacks by limiting the rate of incoming requests

• Ensures fair usage of resources by preventing one client from monopolizing server resources

• Can be implemented using algorithms like token bucket or leaky bucket

• Ex...read more
Answered by AI
Add your answer
Q4. What is the mean by thread, how many ways we can create thread?
Ans. 
A thread is a lightweight sub-process that allows concurrent execution within a process. Threads can be created in multiple ways.
• Threads can be created by extending the Thread class in Java.

• Threads can be created by implementing the Runnable interface in Java.

• Threads can be created using thread pools in Java.

• Threads can be created using asynchronous functions in JavaScript.
Answered by AI
Add your answer
Q5. What is use of thread.join()?
Ans. 
thread.join() is used to wait for a thread to finish its execution before moving on to the next steps.
• thread.join() blocks the current thread until the thread it is called on completes its execution.

• It is commonly used in multi-threaded applications to ensure that all threads have finished before proceeding.

• Without thread.join(), the main thread may continue executing while other threads are still running.

• Example: thre...read more
Answered by AI
Add your answer
Q6. What is the difference between sync and asynchronous call?
Ans. 
Sync call blocks the execution until the response is received, while asynchronous call allows the program to continue executing without waiting for the response.
• Sync call blocks the program execution until the response is received

• Asynchronous call allows the program to continue executing without waiting for the response

• Sync calls are easier to understand and debug, but can lead to performance issues if used excessively

• ...read more
Answered by AI
Add your answer
Q7. How to deploy your service in production server?
Ans. 
Deploying service in production server involves building the application, configuring the server, and monitoring performance.
• Build the application code into a deployable package (e.g. JAR file for Java applications)

• Configure the production server with necessary dependencies and environment variables

• Deploy the application package to the server using tools like Docker, Kubernetes, or manual deployment scripts

• Monitor the ...read more
Answered by AI
Add your answer
Q8. What is use of Jenkins and kubernates?
Ans. 
Jenkins is a continuous integration tool used for automating software development processes, while Kubernetes is a container orchestration platform for managing containerized applications.
• Jenkins is used for automating the building, testing, and deployment of software projects.

• Kubernetes helps in automating the deployment, scaling, and management of containerized applications.

• Jenkins can be integrated with Kubernetes t...read more
Answered by AI
Add your answer
Q9. What is the difference between fail safe and fail fast
Ans. 
Fail safe focuses on ensuring system stability and preventing catastrophic failures, while fail fast prioritizes quick detection and response to errors.
• Fail safe is about designing systems to minimize the impact of failures and ensure stability.

• Fail fast is about quickly detecting and responding to errors to prevent further issues.

• Fail safe often involves redundancy and error checking mechanisms to prevent catastrophic...read more
Answered by AI
Add your answer

Writing URLShortener or LoadBalancer in Java

Q1. ACID definition and Isolation levels
Add your answer
Q2. CAP Theoreme and Distributed transactions
Add your answer

It will be a basic maths questions.

As a general topic of trend in world.

To be known for programming knowledge about us.

Q1. Programming oridanited
Add your answer
Q2. Skill knowledge questions
Add your answer

Q1. Tell me about your self.
Add your answer
Q2. Family background .
Add your answer

20 MCQs + 2 Coding Question

Q1. Trapping Rain Water
Add your answer

Q1. Questions on time and space complexity
Add your answer

Q1. General Discussion
Add your answer

Q1. LLD HLD HM rounds
Add your answer

Mcqs based on cs fundamentals and 2_3 coding questions

Q1. 2-3 DSA questions to be written on paper in the interview itself
Add your answer
Q2. Merge 2 sorted Linked list into 1
Ans. 
Merge two sorted linked lists into one.
• Create a new linked list to store the merged list.

• Compare the values of the nodes from both lists and add the smaller value to the new list.

• Move the pointer of the list with the smaller value to the next node.

• Repeat the comparison and addition until one of the lists is empty.

• Add the remaining nodes from the non-empty list to the new list.

• Return the new merged list.
Answered by AI
Add your answer

Q1. A full cv analysis interview round discussion on all the projects and team work experience
Add your answer