.NET 9 Angular 19 Clean Architecture CQRS

Easy.Platform is a comprehensive framework for building enterprise applications with .NET 9 backend and Angular 19 frontend, featuring Clean Architecture, CQRS, Domain-Driven Design, and event-driven patterns.

Easy.Platform provides a complete foundation for enterprise application development:

• Clean Architecture: Four-layer architecture (Domain, Application, Infrastructure, Presentation) ensuring separation of concerns and testability
• CQRS Pattern: Command Query Responsibility Segregation with fluent validation and event-driven side effects
• Event-Driven Architecture: Domain events and RabbitMQ message bus for cross-service communication
• Multi-Database Support: MongoDB, SQL Server, PostgreSQL with unified repository patterns
• Angular Integration: PlatformVmStore state management, base components, and reactive forms

The framework is battle-tested in production enterprise applications and provides patterns for common challenges like background jobs, data migrations, authorization, and multi-tenancy.

# Backend
dotnet run --project src/Backend/PlatformExampleApp.TextSnippet.Api
# Frontend
cd src/Frontend && npm install && nx serve playground-text-snippet
# Infrastructure
docker-compose -f src/platform-example-app.docker-compose.yml -f src/platform-example-app.docker-compose.override.yml up -d

Detailed setup: Getting Started Guide

Business Documentation: For detailed business module documentation (requirements, workflows, APIs, test specs), see docs/business-features/ with docs/BUSINESS-FEATURES.md as the master index.

This project includes a complete team collaboration system for AI agents, supporting agile workflows from idea capture to release.

team-artifacts/
├── ideas/ # Raw ideas (IDEA-YYMMDD-NNN)
├── pbis/ # Product Backlog Items (PBI-YYMMDD-NNN)
├── test-specs/ # Test specifications (TS-MOD-NNN)
├── design-specs/ # UI/UX specifications
├── qc-reports/ # Quality gate reports
└── templates/ # Artifact templates

Full guide: Team Collaboration Guide

graph TB
 subgraph "Frontend - Nx Workspace"
 subgraph "Apps"
 PLAYGROUND["playground-text-snippet"]
 end
 subgraph "Libraries"
 PLATFORM_CORE["platform-core"]
 PLATFORM_COMP["platform-components"]
 APPS_DOMAINS["apps-domains"]
 end
 PLAYGROUND --> PLATFORM_CORE
 PLAYGROUND --> APPS_DOMAINS
 end
 subgraph "Backend - .NET 9"
 API["TextSnippet.Api"]
 APP["TextSnippet.Application"]
 DOMAIN["TextSnippet.Domain"]
 PERSIST["TextSnippet.Persistence"]
 end
 subgraph "Infrastructure"
 RABBIT["RabbitMQ"]
 REDIS["Redis"]
 DB["MongoDB/SQL/Postgres"]
 end
 PLAYGROUND --> API
 API --> APP
 APP --> DOMAIN
 APP --> PERSIST
 PERSIST --> DB
 APP --> RABBIT
 APP --> REDIS

Full architecture details: Architecture Overview

src/Platform/ # Easy.Platform framework
├── Easy.Platform/ # Core (CQRS, validation, repositories)
├── Easy.Platform.AspNetCore/ # ASP.NET Core integration
├── Easy.Platform.MongoDB/ # MongoDB patterns
├── Easy.Platform.RabbitMQ/ # Message bus
└── Easy.Platform.*/ # Other modules
src/Backend/ # Example microservice
├── *.Api/ # Web API layer
├── *.Application/ # CQRS handlers, jobs, events
├── *.Domain/ # Entities, domain events
├── *.Infrastructure/ # External concerns (storage, external APIs)
└── *.Persistence*/ # Database implementations

src/Frontend/ # Angular 19 Nx workspace
├── apps/
│ └── playground-text-snippet/ # Example app
└── libs/
 ├── platform-core/ # Base classes, utilities
 ├── platform-components/ # Reusable UI components
 ├── apps-domains/ # Business domain code
 ├── apps-domains-components/ # Domain-specific components
 └── apps-shared-components/ # Shared app components

1. Repository Pattern: Use IPlatformQueryableRootRepository<TEntity, TKey>
2. Validation: Use PlatformValidationResult fluent API (never throw)
3. Side Effects: Use entity event handlers (never in command handlers)
4. CQRS: Command + Result + Handler in ONE file
5. DTO Mapping: DTOs own mapping via MapToEntity()

1. Component Hierarchy: AppBaseComponent → Feature Component
2. State Management: PlatformVmStore for complex state
3. API Services: Extend PlatformApiService
4. Subscriptions: Always use untilDestroyed()
5. CSS Naming: BEM convention (block__element --modifier)

Complete patterns: CLAUDE.md

# Backend
dotnet build src/Easy.Platform.sln
dotnet run --project src/Backend/PlatformExampleApp.TextSnippet.Api
dotnet test [Project].csproj
# Frontend
cd src/Frontend
npm install
nx serve playground-text-snippet
nx build playground-text-snippet
nx test platform-core

1. Study Examples: src/Backend/ for backend, src/Frontend/apps/playground-text-snippet/ for frontend
2. Search Codebase: Use grep/glob to find existing patterns
3. Check Documentation: docs/ directory for guides, CLAUDE.md for patterns
4. Read Base Classes: Check platform-core source for available APIs

• Platform Version: Easy.Platform 1.0
• Backend Framework: .NET 9
• Frontend Framework: Angular 19
• Last Updated: February 2026

For detailed code patterns and complete examples, see CLAUDE.md and the working examples in src/Backend/.