Technology Stack

# Technology Stack Table

# Frontend Technology Details

# React Ecosystem

• React 19.x: Concurrent features, automatic batching, Suspense improvements
• TypeScript 5.x: Advanced type inference, decorators, import attributes
• Material-UI 7.x: Theming system, accessibility features, Swiss design compliance
• Recharts 2.x: Declarative charting library for React with TypeScript support
• Zustand 5.x: Minimal boilerplate, TypeScript-first state management
• React Query 5.x: Server state management, caching, background updates

# Development Tools

• Vite 7.x: Fast build times, hot module replacement, optimized bundling
• ESLint 9.x: Code quality and consistency enforcement
• Prettier 3.x: Code formatting standardization
• Tailwind CSS 3.x: Utility-first CSS framework for rapid UI development

# Testing Framework

• Vitest 3.x: Fast unit testing with TypeScript support
• React Testing Library 16.x: Component testing best practices
• Playwright 1.x: End-to-end testing across browsers

# Backend Technology Details

# Java Enterprise Stack

• Java 21 LTS: Long-term support, virtual threads, pattern matching
• Spring Boot 3.x: Auto-configuration, embedded servers, production-ready features
• Spring Security 6.x: OAuth2, JWT, method-level security
• Spring Data JPA: Repository pattern, query generation, transaction management

# Database & Caching

• PostgreSQL 15+ (db.t4g.micro ARM-based, Single-AZ): Advanced SQL features, JSON support, full-text search, cost-optimized
• Caffeine 3.x: Application-level in-memory caching (replaces Redis ElastiCache for cost savings)
• Flyway: Database migration and versioning

# Build & Testing

• Gradle 8.x: Dependency management, multi-project builds, performance optimization
• JUnit 5.x: Modern testing framework with parameterized tests
• Testcontainers 1.x: Integration testing with real databases
• MockMvc: Spring MVC testing framework

# Infrastructure Technology

# AWS Cloud Services (Cost-Optimized)

• AWS ECS Fargate: Serverless container orchestration
• AWS Cognito: User authentication and authorization
• AWS S3: Object storage with CDN integration
• AWS CloudFront: Global content delivery network (cdn.batbern.ch)
• AWS RDS (Single-AZ, db.t4g.micro): Managed PostgreSQL database service (cost-optimized)
• AWS VPC (Single AZ, 1 NAT Gateway): Cost-optimized networking infrastructure
• Note: ElastiCache Redis removed; using application-level Caffeine caching for 83% cost reduction

# Infrastructure as Code

• AWS CDK 2.x: Type-safe infrastructure definition
• TypeScript 5.x: CDK language for infrastructure code
• CloudFormation: AWS native infrastructure templates

# CI/CD Pipeline

• GitHub Actions: Automated workflows and deployments
• Docker: Containerization for consistent deployments
• AWS ECR: Container image registry

# Monitoring & Observability

# Application Monitoring

• AWS CloudWatch: Native AWS service monitoring and logging
• Grafana 10.x: Advanced visualization and alerting
• AWS X-Ray: Distributed tracing and performance insights
• Micrometer: Application metrics collection

# Logging Framework

• SLF4J 2.x: Simple Logging Facade for Java
• Logback 1.x: Structured JSON logging
• MDC: Mapped Diagnostic Context for request correlation

# Development Environment

# Prerequisites

java --version          # Java 21 LTS
node --version         # Node.js 20+
docker --version       # Docker Desktop
aws --version          # AWS CLI v2
cdk --version          # AWS CDK v2.110+
gradle --version       # Gradle 8.5+

# IDE Recommendations

• IntelliJ IDEA: Java/Spring Boot development
• VS Code: Frontend development with TypeScript
• DataGrip: Database development and management

# Browser Support

• Chrome: Latest stable version (primary development and testing)
• Firefox: Latest stable version (cross-browser compatibility)
• Safari: Latest stable version (macOS compatibility)
• Edge: Latest stable version (Windows compatibility)

# Technology Decision Rationale

# Frontend Choices

• React over Vue/Angular: Mature ecosystem, excellent TypeScript support, component reusability
• Material-UI over Custom CSS: Swiss design compliance, accessibility features, rapid development
• Recharts over D3.js: React-native components, simpler API, better TypeScript integration, Material-UI compatible
• Zustand over Redux: Simpler API, less boilerplate, better TypeScript integration
• React Query over SWR: More comprehensive caching, better error handling, request deduplication

# Backend Choices

• Java over Node.js/Python: Enterprise ecosystem, long-term support, team expertise
• Spring Boot over Micronaut/Quarkus: Industry standard, extensive documentation, cloud integration
• PostgreSQL over MySQL/MongoDB: ACID compliance, advanced features, JSON support
• Caffeine (in-memory) over Redis ElastiCache: Cost-effective ($149/month savings), zero network latency, simplified architecture

# Infrastructure Choices

• AWS over Azure/GCP: Comprehensive service offering, CDK support, Swiss region availability
• ECS Fargate over EKS: Simpler operations, serverless scaling, lower management overhead
• CDK over Terraform: Type safety, AWS native, better IDE support
• Single-AZ over Multi-AZ: Cost-effective for low traffic (1000 users/month), acceptable 5-minute manual failover
• ARM-based T4G instances over x86 T3: Better price/performance ratio, 20% cost savings