🏗️ System Design & Architecture Notes Index

A complete guide to learning system design from fundamentals → advanced distributed systems → networking → DevOps → real-time systems.

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⭐ Recommended Learning Path

1. Start with fundamentals → ACID, CAP, NFR, Idempotency
2. Move to core system design → Caching, Databases, Partitioning, HLD
3. Understanding distributed systems → Consensus, Event-driven, Replication
4. Networking & performance → HTTP, load balancing, latency
5. Scaling & HA → Failover, multi-region, resiliency
6. Security → OAuth2, JWT, TLS, OWASP
7. Advanced concepts → CRDT, OT, ABR video streaming
8. DevOps + Kubernetes → Pods, Ingress, Prometheus
9. Design problems → Chat system, Notification system, Rate limiting

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📘 Fundamentals & Design Principles

• 12-Factor App
• ACID
• CAP
• Consistency vs Integrity
• Idempotency
• NFR
• SPOF
• SOLID, SRP, OCP, LSP, DIP vs LSP
• Clear Architecture Principles
• Non-functional No Value Trap
• Six Pillars of System Design

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🗄️ Databases & Storage

Concepts

• SQL vs NoSQL
• Normalization vs Denormalization
• Partition Tolerance
• Partition vs Sharding
• Sharding
• Consistency Models, Eventual Consistency
• MVCC
• Serializable Transactions
• Db Consistency
• DB Durability
• Row-level Locking
• Optimistic vs Pessimistic Locking
• Distributed Locks, Redis Lock

Systems

• Cassandra
• HDFS
• S3
• Timeseries DB

Logs, Storage & Recovery

• Write Ahead Logs
• Redo Logs
• Data Recovery

Replication & Transactions

• Primary Replica Setup
• Replication
• Two Phase Commit
• Saga Pattern

Change Data & Migration

• CDC
• Data Migration Process

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⚡ Performance, Scalability & Caching

Caching

• Caching
• Eviction Policies
• Hot Keys
• Hot Reads/Writes

Performance Engineering

• Latency
• Tail & Request Latencies
• Latency vs Throughput
• CPU Calculation
• Low Latency Patterns

Scaling & Load

• Backpressure
• Real-time Backpressure
• Sudden Traffic Spike
• Buffer Burst

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🛡️ High Availability & Fault Tolerance

• Failover Switching
• Fault Tolerance
• Auto Restart
• RTO RPO
• Resiliency
• Multi-region Deployment
• Leader Election
• Cascading Failures
• Chaos Testing

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🌐 Networking & Infrastructure

Core Networking

• How HTTP Works
• HTTP vs HTTPS
• TCP vs UDP
• Head of Line Blocking
• TLS

Load Balancing

• Load Balancer
• L4 vs L7
• Load Balancer vs Reverse Proxy
• LB vs RP vs API Gateway

Traffic Delivery

• CDN
• Geo DNS

Server Concepts

• Sticky Sessions
• Nginx

API Management

• API Gateway
• Apigee
• REST Call Flow

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📩 Messaging, Streaming & Async Systems

Messaging

• Kafka vs RabbitMQ
• Kafka vs Pulsar vs PubSub
• Webhooks

Streaming

• Redis Streams
• Consumer Lag Monitoring

Architectures

• Push vs Pull
• Asynchronous Decoupling

Real-time

• WebSockets
• Server Sent Events
• Short vs Long Polling
• Long Polling vs WebSockets

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🔐 Security & Authentication

• JWT
• OAuth2
• Secrets Management
• Short Circuit Auth
• SAST vs DAST
• Dependency Vulnerability Checks
• Threat Modeling
• Threat Detection
• DDOS Protection
• Brute Force Protection

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🛠️ Tools, DevOps & Operations

• Spring Boot Health Check
• Kubernetes Pods Restart
• ConfigMap
• Kubernetes Ingress
• Persistent Volume
• Creating Docker Image
• Helm
• PgBouncer
• Prometheus & Grafana
• Telemetry

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🧱 Architecture Patterns & System Design

• Two-tier Architecture
• Project Architecture
• Single Server Design
• CQRS
• Event-driven Architecture
• Event Sourcing, Event Sourcing vs Outbox
• Mono vs Microservices
• Serverfull vs Serverless
• Distributed Rate Limiter
• Retry Mechanism
• Deployment Strategy
• High Scale System Design
• Back-of-the-Envelop Estimation
• Phased Approach
• Post Materializer
• Measure First Approach

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🔍 Search, Indexing & Analytics

• Elastic Search
• Apache Lucene
• Inverted Index
• Text Search Engines
• TF-IDF
• Proximity Search
• Index Fragmentation
• Cursor Pagination

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🎥 Data Processing, Streaming & Video Tech

• Batch vs Streaming
• Adaptive Streaming
• Adaptive Bitrate Streaming (ABR)
• DASH / HLS
• Manifest File Processing
• Chunker Service
• Transcoding
• Micro-batching
• Apache Spark

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💬 System Design Use Cases

• Chat System
• Notifications Design
• Frontend Storage
• WebRTC

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🔢 Identifiers & Utilities

• UUID
• Snowflake ID
• Vanity URL

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📗 Miscellaneous

• Internet
• Encoding
• Download & Upload
• DOD
• CAS – Compare and Swap
• Operational Transformation
• CRDT Deep Dive
• Rule Engine, ACL + Rule Engine

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📑 HTTP Status & Protocol References

• 200 vs 201 vs 202
• 301 vs 302
• 429 vs 503

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🧭 System Design Interview Prep

• System Design Problems – Key Solutions
• Interview Question Bank
• Syllabus

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