System Design

How large-scale systems are designed — from load balancing and caching to database sharding, message queues, and failure strategies.

Scalability

Load Balancers

Caching

CDN & Edge

Sharding

Message Queues

Rate Limiting

Auth at Scale

DB Indexing

Failure Design

Scaling

Scaling strategies, stateless services, and session management.

L4 vs L7, health checks, sticky sessions, and NGINX vs ALB.

Static asset distribution, edge functions, and cache invalidation.

Performance

Redis, CDN, write-through vs write-back, and cache invalidation patterns.

Token bucket, sliding window, leaky bucket, and API quotas.

Data Layer

Horizontal partitioning, read replicas, CAP theorem, and consistency.

Kafka, RabbitMQ, at-least-once vs exactly-once delivery.

B-trees, hash indexes, composite indexes, and query plans.

Resilience

SSO, OAuth2 flows, session vs token, and distributed sessions.

Redundancy, failover, graceful degradation, and chaos engineering.