Software Engineering Principles

A career as a software engineer takes a lot of time. The field is growing rapidly, and engineers are needed in a number of industries including retail, cybersecurity, and artificial intelligence.

To be a successful software engineer, it is important to understand the software engineering principles that will allow you to create robust and adaptable programs. These principles are often discussed during code reviews and can help you write clean, maintainable, and testable programs.

Principle of Least Surprise (PoLA)

Often referred to as the Law of Least Astonishment, this principle emphasizes consistency in user interface design and software development. This reduces the cognitive load on users and helps developers better understand how to use and code the software.

Modularity is another important aspect of this principle. Each module should have as few dependencies as possible. In other words, each module should communicate with a small number of modules and should share as little state as possible with them. This allows the effect of a bug in one module to remain confined to that module and limit its spread.

Communicating these software engineering principles to your team is critical for fostering collaboration and ensuring everyone has the same understanding of the best practices to follow. It’s also important to regularly reevaluate and adjust your design principles to keep them relevant and effective. Consider strategies such as interactive workshops or hands-on learning experiences to help your team understand and apply the principles.

Principle of YAGNI

The YAGNI principle is one of the most powerful software engineering principles. It focuses on only adding functionality when it’s required in the current situation. This allows developers to avoid creating code for future needs that might never be used. It also reduces the risk of overengineering, which is costly for both the team and the company.

When YAGNI is applied correctly, it can help teams deliver faster and more effectively. It can also reduce codebase complexity, which makes it easier for teams to test and maintain their work.

However, YAGNI should not be used as an excuse to ignore design principles like SOLID and KISS. These principles encourage software designers to create a simple and modular codebase that is easy to understand and use. This helps teams develop better applications that are flexible for extending, fixing and refactoring. They can also meet business requirements and provide a smooth user experience.

Principle of Open for Extension (OCP)

This principle advises that software modules should be open for extension but closed to modification. This allows other classes to extend a class’ behavior without touching the original code. This can be done by implementing a subclass of the class and overriding the methods you need. This can also be done by using a framework that supports this kind of dynamic inheritance.

However, it is important to note that this doesn’t mean you should avoid modifying the code. Modifying the original code may be necessary to fix bugs or implement new features. However, it is important to use the Single Responsibility Principle and other design patterns to make sure that your code can be extended without modifying existing code.

Robert Martin’s restatement of this principle focuses on abstract interfaces and polymorphism. This differs from Meyer’s original definition, which advocated implementation inheritance. However, both versions of this principle are equally valid. The main difference is that they focus on different implementations of a module’s behaviors.

Principle of Limited Subscription (LSP)

The Open-Closed Principle (OCP) states that software entities should be open for extension, but closed for modification. This allows you to add functionality by extending the class instead of changing the existing code. This makes your code more flexible and easier to maintain.

The Principle of Limited Subscription (LSP) is similar to the Single Responsibility Principle and deals with how much a derived class changes the behavior of its base class. It also applies to how you can use different objects implementing the same interface.

The goal of LSP is to minimize coupling between classes by using interfaces as contracts. You can do this by separating interfaces into smaller, more focused ones and limiting the number of methods in each. This way, the class implementing the interface only needs to focus on the methods that are relevant for its functionality. This helps keep the interface more readable and reduces dependency on other classes. Moreover, it can also make it easier to change the implementation of an interface without breaking existing code.

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