4 Pillars of System Design
4 Pillars of System Design
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1) 4 Pillars of DSA. (click on DSA to see)
2) LLD (Low-Level Design)
3) HLD (High-Level Design)
4) Knowledge of DevOps.
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4 Pillars of DSA. (click on DSA to see)
Already details available, please check that by clicking DSA above
LLD (Low-Level Design)
Low-Level Design (LLD): After you complete a system design or high-level design,
you have the details of the system components, including the class diagrams, module level, APIs, and database schemas.
It’s all about the implementation details the design patterns and the coding best practices.
Here’s a structured table summarizing Low-Level Design (LLD) concepts:
Aspect | Description | Examples |
---|---|---|
Class Diagrams | Defines classes, attributes, methods, and relationships. | UML Class Diagrams |
Object-Oriented Design (OOD) | Uses OOP principles like SOLID, encapsulation, and inheritance. | Applying SOLID in a UserService class |
Design Patterns | Reusable solutions to common design problems. | Singleton, Factory, Observer |
Database Schema Design | Defines tables, relationships, indexing strategies, and constraints. | ER Diagrams, SQL Table Design |
API Contracts | Defines request/response structures, endpoints, and interfaces. | RESTful API design, OpenAPI Spec |
Sequence Diagrams | Represents object interactions sequentially. | User authentication flow |
Code-Level Considerations | Focuses on modularization, error handling, and logging. | Clean code, logging frameworks, exception handling |
Concurrency Handling | Manages multi-threading, locks, and synchronization. | Mutex, Semaphore, Read-Write Locks |
Performance Optimization | Enhances system efficiency through caching and efficient algorithms. | Redis Caching, Query Optimization |
Security Considerations | Implements authentication, authorization, and data encryption. | OAuth, JWT, SSL, AES Encryption |
4 Pillars of System Design
HLD (High-Level Design)
High-Level Design (HLD) Summary in Tabular Form
Aspect | Description | Examples |
---|---|---|
Architecture Design | Defines system architecture like monolith, microservices, or serverless. | Microservices, Layered Architecture |
Component Diagram | Represents high-level system components and their interactions. | Services, Databases, Message Queues |
Module Breakdown | Splits the system into modules with defined responsibilities. | User Service, Payment Service, Order Service |
Technology Stack | Chooses technologies for frontend, backend, databases, and communication. | React, Node.js, Java, MySQL, Redis, Kafka |
Database Design | Defines major data entities and relationships at a high level. | ERD, Table Relationships |
API Design | Defines service endpoints, protocols (REST, GraphQL, gRPC), and interactions. | RESTful APIs with JSON, OpenAPI Spec |
Scalability Planning | Plans for horizontal/vertical scaling, load balancing, and caching. | Load Balancers, CDN, Auto-Scaling |
Security & Compliance | Defines authentication, authorization, and security mechanisms. | OAuth, JWT, SSL, GDPR Compliance |
Fault Tolerance | Ensures system resilience using retries, failover mechanisms, and redundancy. | Circuit Breaker, Retry Mechanism |
Performance Considerations | Optimizes system response time, throughput, and latency. | Caching, DB Indexing, Async Processing |
External Integrations | Plans integration with third-party services (e.g., payment gateways, APIs). | Stripe, Twilio, AWS S3 |
Knowledge of DevOps
DevOps: As a developer, it is always good to have some knowledge of DevOps to automate deployment, collaboration, and system availability as a senior developer.
DevOps Concepts: Tabular Representation Here is a systematic distilled representation of DevOps Concepts:
4 Pillars of System Design
DevOps Overview
Aspect | Description | Examples/Tools |
---|---|---|
Version Control | Tracks changes in source code. Enables collaboration. | Git, Bitbucket, GitHub, GitLab |
CI/CD (Continuous Integration/Continuous Deployment) | Automates build, test, and deployment processes. | Jenkins, GitHub Actions, GitLab CI, CircleCI |
Infrastructure as Code (IaC) | Manages infrastructure using code instead of manual setup. | Terraform, AWS CloudFormation, Ansible |
Configuration Management | Ensures consistent system configurations across environments. | Ansible, Puppet, Chef, SaltStack |
Containerization | Packages applications with dependencies for consistent deployment. | Docker, Podman |
Orchestration | Manages multiple containers in production environments. | Kubernetes (K8s), Docker Swarm, OpenShift |
Monitoring & Logging | Tracks system health, logs, and performance. | Prometheus, Grafana, ELK Stack (Elasticsearch, Logstash, Kibana), Datadog |
Cloud Services | Uses cloud providers for scalable infrastructure. | AWS, Azure, Google Cloud (GCP) |
Security & Compliance | Implements security best practices, access controls, and audits. | Vault, AWS IAM, SonarQube, SAST, DAST |
Networking & Load Balancing | Distributes traffic and optimizes performance. | Nginx, HAProxy, AWS ALB/ELB |
Release Management | Controls software releases and rollback strategies. | Feature Flags, Blue-Green Deployment, Canary Releases |
Why DevOps Matters for a Senior Developer?
- Automates Deployment → Faster time-to-market
- Improves Collaboration → Bridges Dev & Ops teams
- Enhances Reliability → Reduces downtime and failures
- Optimizes Performance → Efficient monitoring and scaling
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