System Design

roadmap.sh: https://roadmap.sh/system-design

Suggested path through the System Design nodes. Each node links to its lesson when written.

Nodes

Fundamentals

• what-is-system-design-how-to-approach-it
• performance-vs-scalability
• latency-vs-throughput
• availability-vs-consistency-cap-theorem
• consistency-patterns-weak-eventual-strong
• availability-patterns-failover-replication
• availability-in-numbers-the-nines

Networking & delivery

• domain-name-system-dns
• content-delivery-network-cdn-push-vs-pull
• load-balancers-l4-vs-l7-algorithms-active-passive-active-active
• reverse-proxy-vs-load-balancer
• horizontal-vs-vertical-scaling

Application layer

• application-layer-microservices
• service-discovery
• api-gateway-routing-aggregation-offloading

Databases

• rdbms-replication-master-slave-master-master
• federation
• sharding
• denormalization
• sql-tuning
• nosql-key-value-document-wide-column-graph
• sql-vs-nosql-when-to-use-which

Caching

• where-to-cache-client-cdn-web-server-database-application
• caching-strategies-cache-aside-write-through-write-behind-refresh-ahead
• eviction-policies-cache-pitfalls

Asynchronism

• message-queues
• task-queues
• back-pressure
• async-request-reply

Communication

• tcp-vs-udp
• rpc-grpc
• rest-graphql
• http

Resiliency & patterns

• circuit-breaker-retry-throttling-bulkhead
• idempotent-operations
• leader-election
• cqrs-event-sourcing
• event-driven-architecture
• strangler-fig-incremental-migration

Observability

• health-performance-monitoring
• instrumentation-alerts-visualization

Security

• security-basics-authn-authz-encryption-rate-limiting

Resources

See resources.md.

Project ideas

• Design a URL shortener (encode, redirect, scale reads, analytics)
• Design a rate limiter (token bucket vs sliding window) and implement one in playgrounds/go/
• Sketch a news feed / timeline (fan-out on write vs read)