Do you use SOLID principles when writing code?

Yes, I use SOLID principles when writing code because they help create more maintainable, extendable, and readable code. For example:

• Single Responsibility Principle (SRP): each module or class is responsible for one specific task.
• Open/Closed Principle (OCP): classes are open for extension but closed for modification.
• Liskov Substitution Principle (LSP): subclasses can replace base classes without breaking logic.
• Interface Segregation Principle (ISP): it's better to have several specialized interfaces than one universal.
• Dependency Inversion Principle (DIP): dependencies should be based on abstractions, not on concrete implementations.

Example in Node.js (simplified):

// SRP example: class only responsible for user management
class UserService {
  constructor(userRepository) {
    this.userRepository = userRepository;
  }

  createUser(data) {
    // user creation logic
    return this.userRepository.save(data);
  }
}

// DIP example: UserService depends on an abstraction userRepository
class UserRepository {
  save(user) {
    // save to database
  }
}

const userRepository = new UserRepository();
const userService = new UserService(userRepository);

This approach makes the code easier to test and maintain.