6 core patternsPython, JavaScript, GDScript

Design Patterns

Classic patterns for cleaner, more maintainable code.

Learn when to use Observer, Strategy, Factory, and other patterns. Each pattern includes implementations in Python, JavaScript, and GDScript with real-world examples and common pitfalls.

Why Learn Design Patterns?

Design patterns are reusable solutions to common software design problems. They provide a shared vocabulary for developers and help you write code that is easier to understand, test, and maintain.

These patterns are not code you copy-paste. They are templates for solving problems that you adapt to your specific situation. Understanding them helps you recognize when a problem has a known solution and when to avoid over-engineering.

Creational Patterns

Patterns that deal with object creation mechanisms, trying to create objects in a manner suitable to the situation.

Factory Pattern

Beginner

Copy-paste Factory examples in Python, JavaScript, and GDScript. Learn when to use Simple Factory vs Factory Method vs Abstract Factory with real-world scenarios, common mistakes, and a decision flowchart.

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Builder Pattern

Intermediate

Master the Builder pattern with fluent and step-builder variants. Copy-paste examples in Python, JavaScript, and GDScript. Includes validation, common mistakes, and Builder vs Factory comparison.

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Structural Patterns

Patterns that ease design by identifying simple ways to realize relationships among entities.

Decorator Pattern

Intermediate

Copy-paste Decorator examples in Python, JavaScript, and GDScript. Learn wrapper composition, order gotchas, testing strategies, and Decorator vs Proxy/Adapter/Middleware. Includes a timing decorator you can use today.

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Facade Pattern

Beginner

Copy-paste Facade examples in Python, JavaScript, and GDScript. Learn how to design a stable entry-point API, avoid the god-object trap, and compare Facade vs Adapter/Mediator/Service Layer.

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Behavioral Patterns

Patterns that identify common communication patterns among objects and realize these patterns.

Observer Pattern

Intermediate

Learn the Observer pattern for building event-driven systems with production-ready code. Includes memory leak prevention, unsubscribe patterns, and a clear comparison with Pub/Sub, EventEmitter, and Reactive streams.

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Strategy Pattern

Intermediate

Learn the Strategy pattern for encapsulating interchangeable algorithms with production-ready code. Includes functional vs class-based approaches, a clear comparison with State/Command/Template Method patterns, and idiomatic implementations in Python, JavaScript, and GDScript.

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Practice Design Patterns

Learn by doing. Our capstone exercises guide you through implementing these patterns step by step.

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