Interview Prep
SOLID Principles
Five principles of object-oriented design (Robert C. Martin) for building maintainable, flexible software. Each has detailed explanations and around 30 interview questions.
Principles
Pick a principle to study. Every page has layered explanations and an interview question bank you can filter by difficulty.
S — Single Responsibility
A class should have one reason to change.
O — Open/Closed
Open for extension, closed for modification.
L — Liskov Substitution
Subtypes must be substitutable for their base types.
I — Interface Segregation
Many small interfaces beat one fat interface.
D — Dependency Inversion
Depend on abstractions, not concretions.