System Design Masterclass · Staff Track

4-Week Roadmap

One to two concepts per day. Every module: same 7-step structure, interactive sims, Java/Spring Boot implementations against an OTT platform, a fast track (~60–120 min) for familiar ground, and a build-break-measure exercise.

26 modulesFull path ~5h/moduleFast track ~90 min/module

Week 1 — Foundations

THE NUMBERS · THE THEOREMS · THE DATA LAYER
01CachingStrategies · invalidation correctness · stampedes · SWR · multi-tierREADY 02Latency Numbers & EstimationThe ladder · throughput ceilings · 5-step method · budgets · tail amplificationREADY 03CAP & PACELCWhat CAP proves · partition sim · PACELC per system · dataset classificationREADY 04Replication & Consistency ModelsTopologies · lag anomalies · the spectrum · quorums · conflicts & CRDTsREADY 05Partitioning & ShardingStrategies · consistent hashing · rebalancing · hot partitions · query costREADY

Week 2 — Communication

WIRE PROTOCOLS · APIS · TRAFFIC MANAGEMENT
06TCP, UDP & QUICHandshake tax · HOL blocking through HTTP/1.1→3 · why video streams over HTTP anywayREADY 07REST, gRPC, GraphQL & Real-timeSelection advisor · gRPC deadlines & LB caveat · SSE vs WebSocket · versioning disciplineREADY 08Load BalancingAlgorithm race sim · black-hole effect · health checks · draining & slow startREADY 09API Gateways & Service DiscoveryRegistry staleness sim · fat-gateway anti-patterns · the honest mesh decisionREADY 10CDN & Edge ArchitectureShield + collapsing sim · the header contract · live-event delivery · multi-CDNREADY 11DNS, Anycast & Global TrafficTTL failover sim · resolver disobedience · steering stack · RTO/RPO per tierREADY

Week 3 — Resilience & Distributed Patterns

FAILURE IS THE NORMAL CASE
12Timeouts, Retries & BackoffAmplification sim · full jitter · retry budgets · hedged requestsREADY 13Circuit Breakers & BulkheadsBreaker state-machine sim · config-as-claims · fallback ladder · pool isolationREADY 14Rate Limiting & Load SheddingBurst-semantics sim · atomic Redis bucket · priority shedding · goodputREADY 15Event-Driven Architecture & MessagingDelivery-guarantee sim · queue-or-log rule · ordering · DLQ disciplineREADY 16Idempotency & the Exactly-Once IllusionDouble-charge sim · key design · same-transaction dedupe · natural idempotencyREADY 17Sagas & Distributed TransactionsOrchestrated saga sim · pivot ordering · isolation anomalies · semantic locksREADY 18Outbox, CDC & Event SourcingDual-write crash sim · relay design · Debezium · honest ES selectionREADY 19Distributed Locks & CoordinationFencing-token sim · stale holders · lease election · demote-the-lock guideREADY

Week 4 — Security & Scale

TRUST · PROTECTION · PROOF
20Cryptography for ArchitectsPrimitive advisor · envelope encryption & KMS · crypto-shredding · design rulesREADY 21TLS, mTLS & Zero TrustChain-of-trust sim · workload identity · lateral-movement sim · default-denyREADY 22Authentication & AuthorizationRevocation-window sim · refresh rotation · device flow · claims vs lookupsREADY 23DRM & Content SecurityLicense-path sim (your 428 class) · per-tier keys · live rotation · watermarkingREADY 24Observability at ScaleCardinality calculator · tail-sampling sim · burn-rate SLOs · async tracingREADY 25Capacity Planning & CostFleet-sizer model · N−1 checks · pre-scaling for kickoff · cost leversREADY 26Capstone: Design the Playback PathS1→S8 walkthrough · five failure drills · gap audit · the one-pagerREADY

Extensions — Deep Cuts

THE THEORY UNDERNEATH · THE PLATFORM AROUND · THE PROOF ON TOP
27Storage Engine InternalsExtends Week 1 · LSM write-path sim · B-tree trade-offs · WAL as the source of everything · MVCC & bloatREADY 28Edge Security & DDoS MitigationExtends Week 2 · attack/defense-layer sim · anycast & scrubbing · WAF & bots · match-night threat modelREADY 29Container Orchestration & DeploymentExtends Weeks 2/4 · pod lifecycle done right · sidecars vs daemonsets · automated canary sim · feature flagsREADY 30Consensus: Raft & PaxosExtends Weeks 1/3 · election & partition sim · the commit rule · terms as fencing tokens · operating quorumsREADY 31Chaos EngineeringExtends Week 4 · capstone precursor · experiment-method sim · fault catalog mapped to modules · game daysREADY 32Time, Ordering & Failure DetectionExtends Weeks 1/3 · logical-clock playground · HLC & the LWW verdict · Two Generals · φ-accrual & gossipREADY 33Mechanical Sympathy: Concurrency, Laws & IntegrityExtends Weeks 1/4 · CAS/ABA · the Loom decision · Little's Law & USL calculator · checksums & end-to-endREADY

Created by SN.