Modeling a Domain From Scratch Using Domain-Driven Design (DDD)

Title: Modeling a Domain From Scratch Using Domain-Driven Design (DDD)

URL Source: https://medium.com/@mariammaurice/modeling-a-domain-from-scratch-using-domain-driven-design-ddd-f450286ab648?source=rss------programming-5

Published Time: 2026-04-20T18:01:01Z

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# Modeling a Domain From Scratch Using Domain-Driven Design (DDD) | by Mori | Apr, 2026 | Medium

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# Modeling a Domain From Scratch Using Domain-Driven Design (DDD)

## _Stop writing data bags. Start writing software that actually understands your business._

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## The Anemic Model Epidemic

You’ve seen it. A “domain model” that’s just a class with properties and a bunch of `null` checks scattered across services:

public class Order

{

public int Id { get; set; }

public int CustomerId { get; set; }

public List<OrderItem> Items { get; set; } = new();

public decimal Total { get; set; }

public string Status { get; set; } = "Pending";

}
Then the “business logic” lives somewhere else:

public async Task AddItemToOrder(int orderId, int productId, int quantity)

{

var or