System Architecture Diagram

Overview

Architecture Principles

• Microservices: Modular, independently deployable services
• API-First: All interactions through well-defined APIs
• Scalability: Horizontal scaling for high availability
• Security: Defense in depth with multiple security layers
• Observability: Comprehensive logging, monitoring, and tracing

High-Level Architecture

┌─────────────────────────────────────────────────────────────────┐
│                    Client Layer                                 │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │   Web Client    │  │   Mobile App    │  │   Admin Panel    │ │
│  │   (React)       │  │   (React Native)│  │   (React)        │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
└─────────────────────────────────────────────────────────────────┘
                                   │
                                   ▼
┌─────────────────────────────────────────────────────────────────┐
│                   API Gateway Layer                              │
│  ┌─────────────────┐                                           │
│  │   API Gateway   │  (Rate limiting, Authentication, Routing) │
│  │   (Kong/Nginx)  │                                           │
│  └─────────────────┘                                           │
└─────────────────────────────────────────────────────────────────┘
                                   │
                                   ▼
┌─────────────────────────────────────────────────────────────────┐
│                   Service Layer                                  │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │   User Service  │  │ Course Service  │  │Consultation Svc  │ │
│  │   (Node.js)     │  │   (Node.js)     │  │   (Node.js)      │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │ Payment Service │  │Notification Svc │  │ Analytics Svc    │ │
│  │   (Python)      │  │   (Node.js)     │  │   (Python)       │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
└─────────────────────────────────────────────────────────────────┘
                                   │
                                   ▼
┌─────────────────────────────────────────────────────────────────┐
│                   Data Layer                                     │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │  PostgreSQL     │  │    Redis        │  │   OpenSearch  │ │
│  │ (Neon prod,     │  │ (Redis Cloud)   │  │ (Aiven search)   │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
│  ┌─────────────────┐  ┌─────────────────┐                      │
│  │   InstantDB    │  │  Cloudflare R2  │                      │
│  │  (Realtime)    │  │ (Files/Media)   │                      │
│  └─────────────────┘  └─────────────────┘                      │
└─────────────────────────────────────────────────────────────────┘
                                   │
                                   ▼
┌─────────────────────────────────────────────────────────────────┐
│                   Infrastructure Layer                           │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │   Docker / Dokploy  │  │   Self-Hosted   │  │   Nginx Proxy   │ │
│  │ (Containerization│  │ (Linux VPS/Bare)│  │ (Reverse Proxy) │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
│  ┌─────────────────┐  ┌─────────────────┐  ┌─────────────────┐ │
│  │  New Relic APM  │  │ New Relic Logs  │  │   Security      │ │
│  │ (Performance)   │  │ (Aggregation)   │  │ (WAF, SSL)      │ │
│  └─────────────────┘  └─────────────────┘  └─────────────────┘ │
└─────────────────────────────────────────────────────────────────┘

Component Descriptions

Client Layer

• Web Client: React-based single-page application for learners and instructors
• Mobile App: React Native application for iOS and Android
• Admin Panel: React-based dashboard for platform administrators

API Gateway Layer

• API Gateway: Centralized entry point handling authentication, rate limiting, and request routing
• Load Balancer: Distributes traffic across service instances
• CDN: Content delivery network for static assets and media

Service Layer

• User Service: Manages user accounts, authentication, and profiles
• Course Service: Handles course creation, management, and content delivery
• Consultation Service: Manages one-on-one and group consultation sessions
• Payment Service: Processes payments and manages subscriptions
• Notification Service: Handles email, SMS, and in-app notifications
• Analytics Service: Tracks user behavior and generates insights

Data Layer

• PostgreSQL: Primary relational database for structured data
• Redis: In-memory cache for session data and frequently accessed information
• OpenSearch: Search engine for course content and user data
• S3 Storage: Object storage for files, images, and videos

Infrastructure Layer

• Docker / Dokploy: Application containerization and production lifecycle management
• Ingress: Dokploy-managed routing and TLS termination
• Cloudflare R2: High-performance S3 API object storage with zero egress fees
• New Relic: Centralized APM, transaction tracing, and structured log management
• Sentry: Real-time exception tracking and error reporting

Data Flow

1. User Request: Client sends request to API Gateway
2. Authentication: Gateway validates JWT token and user permissions
3. Routing: Request routed to appropriate microservice
4. Business Logic: Service processes request, interacts with databases
5. Response: Service returns data through gateway to client
6. Caching: Frequently accessed data cached in Redis
7. Logging: All requests logged for monitoring and debugging

Security Architecture

• Authentication: JWT tokens with refresh mechanism
• Authorization: Role-based access control (RBAC)
• Encryption: TLS 1.3 for data in transit, AES-256 for data at rest
• API Security: Rate limiting, input validation, SQL injection prevention
• Network Security: VPC isolation, security groups, WAF

Scalability Considerations

• Horizontal Scaling: Services can be scaled independently
• Database Sharding: Data partitioned across multiple database instances
• CDN Integration: Static content served from edge locations
• Auto-scaling: Services scale based on CPU/memory usage
• Read Replicas: Database read operations distributed across replicas

Deployment Architecture

• CI/CD Pipeline: Automated testing and deployment
• Blue-Green Deployment: Zero-downtime deployments
• Feature Flags: Gradual feature rollout and rollback
• Environment Isolation: Separate environments for dev/staging/prod

Monitoring and Observability

• Metrics: Application performance, error rates, user activity
• Logging: Structured logs with correlation IDs
• Tracing: Distributed tracing for request flow
• Alerting: Automated alerts for system issues
• Dashboards: Real-time monitoring dashboards

Technology Stack

Frontend

• React 18
• TypeScript
• Zustand
• React Router
• Axios

Backend

• Node.js (Express/NestJS)
• Python (FastAPI)
• GraphQL/REST APIs
• JWT Authentication

Database

• PostgreSQL 15
• Redis 7
• OpenSearch-compatible Aiven service
• Cloudflare R2 (Object Storage)

Infrastructure

• Dokploy-managed Docker deployment
• Cloudflare/Dokploy ingress and TLS

DevOps & Observability

• GitHub Actions CI/CD
• New Relic APM & Log Management
• Sentry Exception Tracking

Future Considerations

• Micro-frontend Architecture: Independent frontend applications
• Event-Driven Architecture: Asynchronous communication between services
• Multi-Cloud Deployment: Hybrid cloud strategy
• AI/ML Integration: Machine learning for personalized learning
• Blockchain: Credential verification and NFT certificates