Software development is often about managing complexity and change. As applications grow, how do we add new features without breaking existing ones? How do we ensure our code remains maintainable, flexible, and robust? Two core principles from the SOLID acronym offer powerful guidance: the Open/Closed Principle (OCP) and the Liskov Substitution Principle (LSP).
Let’s dive into what these principles mean, why they matter, and how TypeScript helps us implement them effectively.
In modern application development, especially with layered architectures or microservices, data needs to move between different parts of the system. How do we manage this flow cleanly and efficiently? Enter the Data Transfer Object (DTO).
As noted, a fundamental principle is:
A DTO should just contain data, not business logic. It’s a simple, small thing that should do one task only: carry data between processes or layers.
Let’s unpack what DTOs are, why they are crucial, and how they differ from other related concepts like Entities and Domain Objects.
Writing software that works is one thing; writing software that is easy to understand, maintain, extend, and test is another. As applications grow in complexity, adhering to sound design principles becomes crucial for long-term success and sanity. Two fundamental sets of guidelines stand out: the SOLID principles for object-oriented design and the DRY principle.
Let’s break down these concepts to understand how they help us build better software.
The SOLID Principles Coined by Robert C.