#distributed-systems

Design scalable URL shortening service (like TinyURL). Components: 1. API design (REST/GraphQL). 2. Hashing algorithm (Base62). 3. Database schema (NoSQL vs SQL) and partitioning. 4. Cache layer (Redis) for redirect performance. 5. Unique ID generation (KGS - Key Generation Service). 6. Analytics service (async processing). 7. Rate limiting and abuse prevention. 8. High availability and georedundancy strategy.

Design microservices architecture effectively. Principles: 1. Single Responsibility (one service, one business capability). 2. Decentralized Data (each service owns its database). 3. API Gateway (single entry point). 4. Service Discovery (Consul, Eureka). 5. Asynchronous Communication (message queues, events). 6. Circuit Breaker (fault tolerance). 7. Containerization (Docker, Kubernetes). Challenges: distributed tracing, data consistency, testing. Use API versioning. Implement health checks. Centralized logging (ELK). Monitoring (Prometheus, Grafana). Start with monolith, extract services gradually. Not always the right choice - consider team size and complexity.

Design microservices effectively. Patterns: 1. Service per business capability. 2. API Gateway for routing. 3. Service discovery (Consul, Eureka). 4. Circuit breaker for resilience. 5. Event-driven communication. 6. Database per service. 7. Saga pattern for distributed transactions. 8. CQRS for read/write separation. Use Docker and Kubernetes. Implement observability from start.