SOLID Principles in PHP

SOLID represents a series of guidelines that developers can use to, if done well, simplify and clarify their code. While certainly not laws, understanding these concepts will make you a better developer.

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  • 01

    Episode 1 Run Time 12:13

    Single Responsibility Free

    The most popular of the SOLID design principles, the single responsibility principle dictates that a class should have only one reason to change. To illustrate this a bit more, let's dig into a simple example.

  • 02

    Episode 2 Run Time 13:22


    Open-Closed? Huh? This is one of those principles that developers often skip over. Don't! These techniques are paramount to mature design.

  • 03

    Episode 3 Run Time 9:34

    Liskov Substitution

    Coined by Barbara Liskov, this principle states that any implementation of an abstraction (interface) should be substitutable in any place that the abstraction is accepted.

  • 04

    Episode 4 Run Time 10:25

    Interface Segregation

    The Interface Segregation Principle states that a client should never be forced to implement an interface that it doesn’t use. As you'll find, this all comes down to knowledge. Learn what I mean by that in this lesson.

  • 05

    Episode 5 Run Time 9:34

    Dependency Inversion

    There's a common misunderstanding that "dependency inversion" is simply another way to say "dependency injection." However, the two are not the same. So let's dive in and figure this out!