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✅ Master Level
Design Patterns
Factory • Strategy • Observer • Adapter (Pin-to-Pin)
🟢 LEVEL 1
Design Pattern Fundamentals
Understanding the foundation and purpose of design patterns.
1. Introduction to Design Patterns
- What are design patterns
- Purpose of patterns
- Reusability concepts
- Maintainability goals
- Flexibility in design
2. Pattern Categories
- Creational patterns
- Structural patterns
- Behavioral patterns
3. Design Principles Foundation
- Composition over inheritance
- Loose coupling
- High cohesion
- Open/Closed Principle alignment
🟢 LEVEL 2
Factory Pattern (Creational)
Abstracting object creation for flexibility.
4. Factory Pattern Basics
- Object creation abstraction
- Encapsulating instantiation
- Factory method concept
5. Variations
- Simple Factory
- Factory Method
- Abstract Factory (overview)
6. Usage Scenarios
- Dynamic object creation
- Environment-based creation
- Plugin-based architecture
7. Frontend Applications
- Component creation
- API service creation
- Theme/UI variant creation
🟡 LEVEL 3
Strategy Pattern (Behavioral)
Encapsulating algorithms for runtime selection.
8. Strategy Pattern Basics
- Algorithm encapsulation
- Runtime behavior selection
- Strategy interface concept
9. Implementation Concepts
- Strategy selection
- Context object
- Replaceable algorithms
10. Usage Scenarios
- Sorting strategies
- Payment methods
- Validation strategies
- Feature toggles
11. Frontend Applications
- Form validation logic
- Data formatting strategies
- Rendering strategies
🟡 LEVEL 4
Observer Pattern (Behavioral)
Managing one-to-many dependencies and events.
12. Observer Pattern Basics
- Publisher–Subscriber model
- Event-driven communication
- One-to-many dependency
13. Implementation Concepts
- Subject
- Observer
- Subscription management
- Notification flow
14. Usage Scenarios
- Event systems
- State updates
- Real-time updates
15. Frontend Applications
- State management
- Event emitters
- UI reactivity
🟠 LEVEL 5
Adapter Pattern (Structural)
Converting interfaces for compatibility.
16. Adapter Pattern Basics
- Interface conversion
- Compatibility layer
- Wrapping existing functionality
17. Implementation Concepts
- Target interface
- Adaptee
- Adapter wrapper
18. Usage Scenarios
- Third-party integrations
- Legacy system integration
- API response transformation
19. Frontend Applications
- API data mapping
- UI library adaptation
- Backend response normalization
🔵 LEVEL 6
Pattern Composition
Combining patterns for complex scenarios.
20. Combining Patterns
- Factory + Strategy
- Observer + Strategy
- Adapter + Factory
21. Pattern Selection
- When to use patterns
- Avoiding over-engineering
- Identifying code smells
🔴 LEVEL 7
Architecture Level Usage
Patterns at scale and in large systems.
22. Patterns in Large Applications
- Module boundaries
- Plugin systems
- Extensible architecture
23. Patterns with SOLID Principles
- SRP alignment
- OCP alignment
- Dependency inversion usage
⭐ Senior Frontend Focus (Must Master)
Critical design patterns for senior-level frontend engineers:
- Strategy pattern in hooks/services
- Observer pattern in state management
- Adapter pattern in API layer
- Factory pattern in component/service creation
- Pattern-driven scalable UI architecture