title:: Avoid Framework Imports in Inner Layers
impact:: CRITICAL
impactDescription:: prevents framework lock-in, enables 10× faster unit tests
tags:: dep, frameworks, imports, isolation

Avoid Framework Imports in Inner Layers

Entities and use cases must never import framework-specific types. Framework dependencies in inner layers create tight coupling that makes testing slow and migration impossible.

Incorrect (use case imports framework types):

// Application/UseCases/ProcessPaymentUseCase.cs
using Microsoft.EntityFrameworkCore;
using Microsoft.AspNetCore.Http;
using Newtonsoft.Json;

public class ProcessPaymentUseCase
{
    private readonly DbContext _context;  // EF Core dependency
    private readonly IHttpContextAccessor _http;  // ASP.NET dependency

    public async Task Execute(PaymentRequest request)
    {
        var userId = _http.HttpContext.User.Identity.Name;
        var payment = JsonConvert.DeserializeObject<Payment>(request.Data);
        _context.Payments.Add(payment);
        await _context.SaveChangesAsync();
    }
}

Correct (use case depends only on abstractions):

// Application/UseCases/ProcessPaymentUseCase.cs
// No framework imports

public class ProcessPaymentUseCase
{
    private readonly IPaymentRepository _payments;
    private readonly ICurrentUserProvider _currentUser;

    public async Task Execute(PaymentCommand command)
    {
        var userId = _currentUser.GetUserId();
        var payment = new Payment(command.Amount, command.Currency, userId);
        await _payments.Save(payment);
    }
}

// Infrastructure/Persistence/EfPaymentRepository.cs
using Microsoft.EntityFrameworkCore;

public class EfPaymentRepository : IPaymentRepository
{
    private readonly DbContext _context;
    // Framework usage isolated to infrastructure
}

Benefits:

Use case tests run without framework bootstrapping
Framework can be upgraded or replaced independently
Business logic remains readable without framework noise

Reference: Clean Architecture - Frameworks are Details

clean-architecture

evals

SKILL.md

solid-principles

tile.json

pantheon-ai/design-principles

dep-no-framework-imports.md.css-3qkkll{font-size:var(--chakra-font-sizes-sm);font-weight:var(--chakra-font-weights-normal);color:var(--chakra-colors-gray-300);}clean-architecture/references/

Avoid Framework Imports in Inner Layers

dep-no-framework-imports.mdclean-architecture/references/