System Design Interview: Financial Exchange and Matching Engine
Exchange Architecture Overview A financial exchange matches buy and sell orders — a buyer willing to pay $100 for AAPL […]
System Design
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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: Social Graph and Friend Recommendations
Social Graph Requirements A social graph stores relationships between users (friendships, follows, connections) and enables graph queries: friends of friends,
System Design
System Design Interview: Job Scheduler and Task Queue
Why Task Queues? Task queues decouple work production from work execution. Instead of processing a long-running task synchronously (blocking the
System Design
System Design Interview: Notification System at Scale
Notification System Requirements A notification system routes messages from producers (application events) to consumers (users) via multiple channels: push notifications
System Design
System Design Interview: Database Indexing and Query Optimization
Why Indexing Matters Without an index, a SELECT with a WHERE clause requires a sequential scan — reading every row
System Design
System Design Interview: Real-Time Collaborative Editing (Google Docs)
The Collaboration Problem Real-time collaborative editing lets multiple users edit the same document simultaneously with all changes visible to all
System Design
System Design Interview: API Rate Limiting and Throttling
Why Rate Limiting? Rate limiting protects services from overload, abuse, and cost explosions. Without it: a single misbehaving client can
System Design
System Design Interview: Secret Management and PKI (Vault, AWS Secrets Manager)
Why Secret Management Matters Secrets (database passwords, API keys, TLS certificates, SSH keys) are the crown jewels of any system.
System Design
System Design Interview: Log Aggregation and Observability Pipeline
Why Log Aggregation? With hundreds of microservices each running multiple replicas, logs are scattered across thousands of containers. Without centralized
System Design
System Design Interview: Multi-Region Active-Active Architecture
Why Multi-Region Active-Active? A single-region active-passive setup (one primary region serves traffic, one standby region for failover) has two problems:
System Design
System Design Interview: Global Content Delivery and Edge Computing
Beyond Basic CDN: Edge Computing A CDN (Content Delivery Network) has historically served static assets — images, CSS, JS —
System Design
System Design Interview: Kubernetes Autoscaling (HPA, VPA, KEDA, and Cluster Autoscaler)
Why Autoscaling? Manual capacity planning is expensive and error-prone. Too much capacity wastes money; too little causes outages under traffic
System Design
System Design Interview: Two-Phase Commit and Distributed Transactions
The Distributed Transaction Problem A transaction that spans multiple databases or services must either fully commit on all participants or
System Design
System Design Interview: Data Warehouse and OLAP Architecture
What Is a Data Warehouse? A data warehouse (DW) is an analytical database optimized for reading large volumes of historical
System Design
System Design Interview: Service Mesh and Microservice Communication
What Is a Service Mesh? A service mesh is a dedicated infrastructure layer for managing service-to-service communication in a microservices