System Design Interview: GraphQL API at Scale
Why GraphQL for Large APIs GraphQL solves two fundamental REST API problems: over-fetching (the response includes fields the client doesn’t […]
System Design
System Design
Learn to design scalable, reliable systems that handle millions of users. System design interviews test your ability to architect real-world applications, considering tradeoffs, scalability, and best practices.
Core Topics:
Scalability: Load balancing, horizontal vs vertical scaling
Storage: Databases (SQL vs NoSQL), caching (Redis, Memcached)
Reliability: Replication, failover, disaster recovery
Performance: CDNs, caching strategies, database indexing
Common Design Questions:
Design URL shortener (bit.ly)
Design rate limiter
Design Twitter/Instagram feed
Design messaging system (WhatsApp)
Design file storage (Dropbox)
Interview Level: Senior engineers (L5+) at FAANG companies. Requires 3-5+ years experience to tackle effectively.
Preparation: Study system design patterns, understand distributed systems fundamentals, and practice mock interviews.
System Design
System Design Interview: Machine Learning Training Infrastructure
Why ML Training Infrastructure Is a System Design Interview Topic Companies building AI products at scale — OpenAI, Google, Meta,
System Design
System Design Interview: Event Sourcing and CQRS
What Is Event Sourcing? Traditional systems store the current state of data (the latest balance in a bank account, the
System Design
System Design Interview: Multi-Tenant SaaS Architecture
What Is a Multi-Tenant Architecture? Multi-tenancy means a single instance of a software application serves multiple customers (tenants), with each
System Design
System Design Interview: Database Replication and High Availability
Why Database Replication? A single database server is a single point of failure. Replication copies data from a primary (write)
System Design
System Design Interview: Real-Time Bidding Platform (Ad Exchange)
The global programmatic advertising market is $500B. Every time a web page loads, a real-time auction runs in under 100
System Design
System Design Interview: Ticketing System (Ticketmaster)
Ticketmaster sells 500M+ tickets per year. A Taylor Swift tour launch can generate 3.5 billion system requests in a single
System Design
System Design Interview: Ride-Sharing App (Uber / Lyft)
Uber operates in 70+ countries with 5M+ trips per day and 4M+ drivers. Designing a ride-sharing app covers real-time geospatial
System Design
System Design Interview: Fraud Detection System
Payment fraud costs $32 billion annually. Every payment processor, bank, and marketplace needs a fraud detection system that identifies fraudulent
System Design
System Design Interview: E-Commerce Platform (Amazon)
Amazon processes 100K+ orders per minute on Prime Day. Designing an e-commerce platform covers product catalog management, inventory at scale,
System Design
System Design Interview: Code Repository and CI/CD (GitHub / GitLab)
GitHub hosts 300M repositories and processes 2B+ Git operations daily. Designing a code hosting platform combines distributed storage (Git objects),
System Design
System Design Interview: Music Streaming Service (Spotify)
Spotify serves 600M users, 100M tracks, and 9M daily podcast episodes. Designing a music streaming service covers audio delivery, catalog
System Design
System Design Interview: Distributed Task Queue (Celery / SQS / Sidekiq)
A distributed task queue decouples work production from work execution. Instead of processing a request synchronously (blocking the HTTP response),
System Design
System Design Interview: Data Pipeline and ETL System (Airflow / Spark)
What Is a Data Pipeline? A data pipeline moves and transforms data from source systems (databases, APIs, event streams) to
System Design
System Design Interview: Microservices Architecture Patterns
Monolith vs Microservices A monolith deploys all application functionality as one unit. Simple to develop initially, but becomes harder to