Building enterprise web platforms and distributed services requires architectures that stay clean, maintainable, and testable even as business requirements grow over years. Here is how DRG NEXORA structures enterprise ASP.NET Core applications.

1. Separation of Concerns & Onion Layering

We structure our solutions into four distinct layers where the domain model sits strictly in the center, completely isolated from external database concerns:

• Domain Layer: Pure enterprise business entities, value objects, and domain events without external NuGet dependencies.
• Application Layer: CQRS Commands, Queries, MediatR Handlers, validation rules (FluentValidation), and interfaces.
• Infrastructure Layer: Entity Framework Core DbContext, SQL Server migrations, caching, and external service clients.
• Presentation / Web API: Thin controllers or Minimal APIs returning typed DTOs consumed by Angular or standalone WPF desktop clients.

"By decoupling your business logic through CQRS and MediatR, command mutations and query read models can be tuned independently without introducing side-effects to existing endpoints."

2. Optimizing Entity Framework Core with SQL Server

To achieve sub-50ms API response times on heavy database tables, we implement compiled queries, .AsNoTracking() for read-only operations, batch updates via EF Core Bulk extensions, and properly indexed Foreign Keys.

3. End-to-End Type Safety with Angular

We generate TypeScript interfaces directly from C# DTOs, ensuring that when our ASP.NET Core backend updates a contract, the Angular frontend immediately flags any compilation discrepancies before code is pushed to production.