// Phase 3 · Build & ship like a pro · course 6

Object-Oriented Programming & Clean Code

Write code other engineers love to work with: objects and classes, clean design, testing and refactoring, the habits big tech checks in code review.

1. 1Classes & Objects in JavaScriptModel real things with classes, the backbone of most large codebases.10 min
2. 2Encapsulation: Protecting Your DataHide internals behind a clear interface so nobody can put an object into a broken state.10 min
3. 3Inheritance vs CompositionShare behavior the flexible way. One of the most-asked OOP design questions.11 min
4. 4SOLID Principles in Plain EnglishFive design rules that keep code easy to change, with a hands-on refactor.12 min
5. 5Clean Code & RefactoringTurn messy code into readable code without changing what it does, protected by tests.12 min
6. 6Unit Testing & Test-Driven DevelopmentWrite tests first, then make them pass. The habit that makes you trustworthy on a team.12 min
7. 7Design patterns you'll actually useComing soon
8. 8Code review like a senior engineerComing soon