GitHub Copilot Instructions for Lakeside Mutual

This directory contains comprehensive GitHub Copilot instructions to help AI assistants understand and work effectively with the Lakeside Mutual project.

Files Overview

📋 copilot-instructions.md

Main project instructions - Start here for overall project understanding

• Project overview and business domain
• Architecture principles and bounded contexts
• Technology stack (Java/Spring Boot, React/TypeScript)
• Code generation rules and naming conventions
• Development guidelines and quality standards

⚙️ copilot-backend.md

Backend-specific instructions - Java/Spring Boot microservices development

• Hexagonal architecture implementation
• DDD tactical patterns (Entities, Value Objects, Aggregates)
• Spring Boot configuration and patterns
• Repository and service layer implementation
• Event-driven architecture patterns
• Testing strategies for backend code

🎨 copilot-frontend.md

Frontend-specific instructions - React/TypeScript applications

• TypeScript patterns and strict typing
• React functional components and hooks
• Redux with Redux Toolkit state management
• Material UI component patterns
• Service layer and API integration
• Error handling and performance optimization

🏗️ copilot-ddd.md

Domain-Driven Design patterns - Core DDD implementation guidance

• Ubiquitous language definitions
• Bounded context implementation
• Aggregate design and invariant protection
• Domain events and cross-context integration
• Anti-corruption layers
• Repository and domain service patterns

🧪 copilot-testing.md

Testing strategies and patterns - Comprehensive testing approach

• Testing pyramid implementation
• Unit testing for domain logic
• Integration testing with Testcontainers
• Architecture testing with ArchUnit
• Frontend component and hook testing
• End-to-end testing with Playwright

How to Use These Instructions

For Developers

1. Start with the main instructions to understand the project context
2. Reference specific files based on what you're working on:
   • Backend development → copilot-backend.md
   • Frontend development → copilot-frontend.md
   • Domain modeling → copilot-ddd.md
   • Writing tests → copilot-testing.md

For AI Assistants

These instructions provide:

• Context about the business domain (insurance company)
• Architectural constraints that must be respected
• Code patterns and examples for consistent implementation
• Testing requirements for quality assurance
• Technology-specific guidance for different parts of the stack

Key Principles to Remember

Domain-Driven Design

• Respect bounded context boundaries - Never access other contexts directly
• Use ubiquitous language consistently across code and documentation
• Protect aggregate invariants through proper encapsulation
• Publish domain events for cross-context communication

Code Quality

• Follow established patterns shown in the examples
• Maintain high test coverage with meaningful tests
• Use proper error handling with domain-specific exceptions
• Document architectural decisions when making significant changes

Architecture

• Hexagonal architecture for backend services
• Clean separation between domain, application, infrastructure, and interface layers
• Event-driven communication between bounded contexts
• API-first design with proper DTOs and validation

Project Context

Business Domain

Lakeside Mutual is an insurance company with these core capabilities:

• Customer Management - Registration, profiles, preferences
• Policy Management - Creation, quotes, renewals, coverage
• Claims Processing - Submission, assessment, settlement
• Billing & Payments - Premium calculations, invoicing
• Risk Assessment - Underwriting and risk evaluation

Technology Stack

• Backend: Java 17, Spring Boot 3.x, PostgreSQL/MongoDB, Kafka
• Frontend: TypeScript 5.x, React 18.x, Redux Toolkit, Material UI
• Infrastructure: Docker, Kubernetes, Terraform
• Testing: JUnit 5, Jest, Playwright, Testcontainers

Regulatory Requirements

As an insurance company, consider:

• Data privacy and protection requirements
• Audit trails for all business operations
• Regulatory compliance with insurance laws
• Financial accuracy in calculations and reporting

Contributing to These Instructions

When updating these instructions:

1. Keep examples current with the actual codebase
2. Maintain consistency across all instruction files
3. Update cross-references when restructuring
4. Test examples to ensure they work as documented
5. Consider the AI assistant perspective when writing guidance

Related Documentation

For more project context, also reference:

• Domain Overview - Business domain understanding
• Bounded Contexts - Context boundaries and relationships
• Development Guidelines - Detailed development practices
• Architecture ADRs - Architectural decision records

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These instructions are designed to help both human developers and AI assistants build high-quality, maintainable code that respects the domain model and architectural principles of the Lakeside Mutual project.