Top 250 System Design Interview Questions and Answers

A system for managing college fests

• Create a website for event registration and ticketing

• Develop a mobile app for real-time updates and notifications

• Implement a database to store event details and participant information

• Integrate payment gateway for o...read more

Design HLD for rider management system

• Use microservices architecture for scalability and flexibility

• Implement user authentication and authorization for security

• Include features like ride tracking, payment processing, and feedback system

• Utilize databa...read more

Use a data structure like a hash table to store contacts in a phone book.

• Use a hash table to store contacts with keys as names and values as contact information

• Each contact entry can be a structure containing fields like name, phone number, email, et...read more

Design a system for users to subscribe to topics and receive notifications for new messages.

• Create a user profile where they can select topics of interest to subscribe to.

• Implement a messaging system that sends notifications to users when new message...read more

Framework designs are the structure and organization of a software framework, including its components and interactions.

• Framework designs define the overall architecture of a software system

• They include the arrangement of components, their relationsh...read more

Design a system for messaging multiple teams at a time.

• Implement a messaging platform with channels for each team

• Allow users to subscribe to multiple teams' channels

• Provide options for real-time messaging and notifications

• Include features like file s...read more

Design YouTube as microservice

• Use microservices architecture to break down the functionalities of YouTube

• Create separate services for video upload, video processing, video storage, user authentication, search, recommendation, etc.

• Use message queues t...read more

Design a system to allow users to claim 6M burgers in 10 minutes

• Implement a scalable backend system to handle high volume of requests

• Use load balancing to distribute requests evenly across servers

• Set up a queue system to manage incoming requests and ...read more

Design a bookmyshow system

• Design a system to book and manage movie tickets

• Consider features like seat selection, payment, and ticket cancellation

• Include user authentication and authorization

• Implement a database to store movie and theater information

• C...read more

To improve QPS of a production system, optimize code, use caching, scale horizontally, and use load balancers.

• Optimize code to reduce processing time

• Use caching to reduce database queries

• Scale horizontally by adding more servers

• Use load balancers to ...read more

Design a system for putting newspapers using classes and functions

• Create a Newspaper class with attributes like title, date, and content

• Create a Publisher class with methods to publish and distribute newspapers

• Create a Subscriber class with methods t...read more

Capacity planning involves forecasting demand and allocating resources to meet that demand.

• Forecasting demand based on historical data and market trends

• Allocating resources such as labor, equipment, and inventory

• Using tools such as ERP systems and si...read more

Implement a system to check inventory when user clicks checkout on an Ecommerce App

• Create a database to store inventory levels for each product

• Implement a function that deducts the quantity of items in the cart from the available inventory

• Display a m...read more

Designing a parking lot system involves layout planning, ticketing system, payment methods, security measures, and efficient traffic flow.

• Layout planning to maximize space and accommodate different types of vehicles

• Implementing a ticketing system for...read more

A cab booking system designed using OOP principles

• Create classes for Cab, Customer, Driver, and Booking

• Use inheritance and polymorphism to handle different types of cabs and bookings

• Implement methods for booking a cab, assigning a driver, and calcula...read more

We scaled the system by implementing horizontal scaling and load balancing.

• Implemented horizontal scaling by adding more servers to the system

• Implemented load balancing to distribute the workload evenly across servers

• Used caching to reduce database l...read more

Achieving high availability and zero downtime with an IDM system involves redundancy, load balancing, disaster recovery planning, and continuous monitoring.

• Implementing redundancy by having multiple servers for failover

• Utilizing load balancing to dis...read more

Design a URL shortener with database and necessary components

• Use a unique identifier for each URL to generate short links

• Store the original URL and corresponding short link in a database

• Implement a redirect mechanism to redirect short links to origin...read more

The low-level design of an e-commerce website involves detailing the architecture, components, and interactions of the system.

• Define the architecture including front-end, back-end, and database components

• Detail the interactions between components suc...read more

Design a notification system supporting immediate, delayed, and repeated notifications

• Use a queue to manage notifications with different delivery times

• Include options for immediate, delayed, and repeated notifications

• Allow users to set preferences fo...read more

Splitwise is a system for managing shared expenses among groups of people.

• Classes: User, Expense, Group

• Functions: addExpense(), settleUp(), calculateBalance()

Rate limiter can be designed using token bucket algorithm to control the rate of requests.

• Use token bucket algorithm to control the rate of requests

• Set a limit on the number of requests allowed within a certain time frame

• Track the number of requests ...read more

Design a cab booking system for efficient and convenient service.

• Implement a user-friendly mobile app and website for booking cabs.

• Include features like real-time tracking, fare estimation, and driver ratings.

• Integrate payment options for seamless tr...read more

Designing a scalable system involves considering factors like load balancing, horizontal scaling, and fault tolerance.

• Utilize load balancing to distribute traffic evenly across servers.

• Implement horizontal scaling by adding more servers to handle inc...read more

I choose the respiratory system.

• The respiratory system is responsible for breathing and gas exchange.

• It includes the lungs, trachea, bronchi, and alveoli.

• The process of respiration involves inhaling oxygen and exhaling carbon dioxide.

• Common respirato...read more

Designing an application like Instagram involves creating a platform for sharing photos and videos with social networking features.

• Implement user profiles with the ability to upload, like, comment, and share photos/videos

• Develop a news feed algorithm...read more

Designing an API to receive messages at a specified URL

• Define the endpoint URL for receiving messages

• Implement authentication and authorization mechanisms to ensure secure access

• Use HTTP methods like POST for sending messages to the API

• Include error ...read more