System Design Questions with Brief Answers :
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Design a URL shortening service like Bitly.
Use a hash function to generate short codes and store the mapping in a database for fast redirection. -
Design a file storage system like Google Drive.
Use cloud storage for files and a relational database for metadata, with access control and versioning. -
Design a cache system (e.g., LRU cache).
Use a hash map and doubly linked list to implement the LRU eviction policy. -
Design a simple social media platform (e.g., Instagram).
Store user data in a NoSQL database, with image storage in the cloud and real-time notifications via WebSockets. -
Design an e-commerce checkout system.
Use a transactional system with a relational database for orders, payment gateway integration, and inventory management. -
Design a real-time messaging system (e.g., WhatsApp).
Use WebSockets for real-time communication and store messages in a distributed database. -
Design a video streaming service (e.g., YouTube).
Store videos in cloud storage, use CDN for content delivery, and relational databases for user interactions. -
Design a content delivery network (CDN).
Use globally distributed edge servers to cache content, reducing latency, and routing requests via DNS. -
Design a recommendation engine (e.g., Netflix recommendations).
Use collaborative or content-based filtering with a NoSQL database to store user behavior and content metadata. -
Design a rate limiter system.
Use token bucket or leaky bucket algorithms with Redis to limit requests and prevent abuse. -
Design a real-time analytics system (e.g., web traffic monitoring).
Use stream processing frameworks like Kafka and Spark, and store data in time-series databases. -
Design a microservices architecture for a large application.
Use REST APIs for communication, Docker for containerization, and Kubernetes for orchestration. -
Design a distributed job scheduler.
Use a distributed queue (e.g., RabbitMQ), with worker nodes to process tasks concurrently. -
Design a highly available database system.
Use replication, sharding, and consistent hashing to ensure fault tolerance and scalability. -
Design a search engine.
Use an inverted index to map keywords to documents and employ ranking algorithms like PageRank. -
Design an online ticket booking system (e.g., for movies, flights).
Use a relational database for seat reservations, with a real-time system for concurrency control. -
Design a payment gateway system.
Use encryption for security, integrate with external payment providers, and implement fraud detection. -
Design a location-based service (e.g., Uber).
Use real-time GPS data and geospatial indexing for ride dispatching and tracking. -
Design a real-time collaboration platform (e.g., Google Docs).
Use WebSockets for live editing, CRDTs for conflict-free concurrent updates, and distributed storage. -
Design a video conferencing system (e.g., Zoom).
Use WebRTC for peer-to-peer video/audio streaming and TURN/STUN servers for NAT traversal. -
Design a blogging platform.
Use a NoSQL database for posts, tags, and comments, with caching for high-traffic content. -
Design a notification system.
Use push notifications with a message queue to ensure scalability and delivery reliability. -
Design a URL redirection service (e.g., 301 redirect).
Store original URLs and their redirection URLs in a key-value store and redirect based on the key. -
Design a voting system (e.g., elections).
Use a relational database for votes, implement safeguards against duplicate voting, and ensure privacy. -
Design a file sharing service.
Store files in cloud storage, use a database for user and permission management, and implement file versioning. -
Design a job queue system (e.g., for background tasks).
Use a message broker like RabbitMQ or Kafka to manage queues, with workers to process jobs. -
Design a system for sending emails.
Use an SMTP server to send emails, with a database for managing email queues and delivery logs. -
Design a cloud-based analytics dashboard.
Use a distributed data storage system and a dashboard frontend that queries real-time analytics data. -
Design a file compression service.
Use compression algorithms (e.g., gzip) to reduce file size and store compressed files in cloud storage. -
Design a monitoring system for server health.
Use a distributed system to collect metrics, store them in a time-series database, and use alerts based on thresholds.