Top 5 Design Patterns Every Backend Developer Must Know in 2024

Top 5 Design Patterns Every Backend Developer Must Know in 2024


Design patterns are essential tools for backend developers to create scalable, maintainable, and efficient systems. In this post, we’ll cover the top 5 design patterns every backend developer should know in 2024. We’ll also show how Coudo AI can help you master these patterns with practical examples and challenges.


1. Singleton Pattern

The Singleton pattern ensures a class has only one instance and provides a global point of access to it. This is particularly useful for managing shared resources like database connections or configuration settings.

When to Use:

  • Logging services.

  • Database connection pools.

  • Configuration managers.

Example Diagram:

Singleton pattern class diagram

Learn It on Coudo AI:

Explore how Singleton is applied in backend systems through real-world scenarios by solveing Singleton Pattern: Game Settings Manager.


2. Factory Method Pattern

The Factory Method pattern provides an interface for creating objects in a superclass but allows subclasses to alter the type of objects that will be created. This promotes loose coupling between client code and the classes it instantiates.

When to Use:

  • When you need to create objects without specifying the exact class.

  • For implementing plugin architectures.

Example Diagram:

Factory method class diagram

Learn It on Coudo AI:

Solve Factory Method: Create an Enemy Spawner to understand how factories simplify object creation.


3. Observer Pattern

The Observer pattern allows one-to-many dependencies, so when one object changes state, all its dependents are notified. This is widely used in event-driven architectures.

When to Use:

  • Implementing event listeners.

  • Messaging systems like Kafka or RabbitMQ.

  • Real-time systems.

Example Diagram:

Observer pattern class diagram


4. Strategy Pattern

The Strategy pattern defines a family of algorithms, encapsulates each one, and makes them interchangeable. It helps in adhering to the open/closed principle.

When to Use:

  • Implementing payment methods (e.g., credit card, PayPal, etc.).

  • Sorting algorithms.

  • Validation logic.


5. Builder Pattern

The Builder pattern helps construct complex objects step by step. Unlike the Factory pattern, Builder focuses on creating objects with multiple configurations.

When to Use:

  • When an object requires many configuration options.

  • For building SQL queries.


Why Coudo AI?

Coudo AI offers a hands-on learning experience where you can solve real-world problems based on these patterns. For instance:

  • Practice Singleton and Factory Method with our challenges.

  • Get AI-driven feedback on your solutions and UML diagrams.

Ready to master design patterns? Head over to Coudo AI and start solving!