Business application development, technical debt reduction

When developers are pressed for time or deadlines, they may choose solutions that work quickly but aren’t optimal in the long run. These choices can include using duplicate code, not following good programming practices, or omitting proper testing. Every time such a decision is made, it’s as if the team is “borrowing” time, knowing that they will have to “pay back” later by fixing these imperfections, which contributes to the accumulation of technical debt .

The consequences of technical debt are numerous and significant . Just as financial debt accumulates with interest, technical debt becomes increasingly expensive to “repay” over time. Code becomes harder to maintain, understand, and evolve. Bugs become more frequent and harder to fix. Adding new features takes longer and longer. These negative effects illustrate the consequences of technical debt, which can seriously compromise the quality and sustainability of a software project.

To prevent and reduce technical debt, several key principles must be implemented:

1. Clean code as a prevention strategy : By adopting clean code practices , developers create cleaner, more modular, and maintainable code from the start. This acts as a “thrift” that prevents the accumulation of technical debt. Best practices include well-thought-out architecture, regular testing, and continuous refactoring.
2. Regular refactoring : It is crucial to continually improve the structure of the code without changing its external behavior. This practice helps maintain the quality of the code over time and makes future modifications easier.
3. Compliance with SOLID principles : Applying object-oriented design principles (Single responsibility, Open-closed, Liskov substitution, Interface segregation, Dependency inversion) helps create more modular, flexible and maintainable code.
4. Automated Testing : Maintaining a comprehensive test suite is essential to facilitate changes with confidence. This helps detect regressions quickly and ensures that new features do not introduce bugs.
5. Up-to-date documentation : Keeping documentation in sync with the code is crucial to make the project easier to understand and maintain, especially when new developers join the team.
6. Systematic code reviews : Implementing a peer review process helps maintain code quality, share knowledge within the team, and detect potential issues before they accumulate.
7. Clean code as a payoff strategy : When technical debt already exists, clean code offers strategies to “payoff” it. This may involve refactoring existing code, improving test coverage, or restructuring parts of the system. This approach helps to gradually reduce technical debt and improve code quality.

Ensuring sustainability and scalability helps ensure the viability and competitiveness of software projects . By maintaining clean code and applying these key principles, projects remain flexible and adaptable to future changes. This allows teams to respond more quickly to new market requirements or technology changes. In the long run, this translates into lower maintenance costs and a longer lifespan for the software.

Reducing technical debt is not only a good practice, but a necessity for any serious software development company. It helps ensure the quality, maintainability and sustainability of projects, while promoting innovation and adaptability in a constantly changing technological environment.

// Code with technical debt
class UserManager {
    private $db;

    public function __construct($db) {
        $this->db = $db;
    }

    public function createUser($userData) {
        // Direct validation in the method
        if (empty($userData['name']) || empty($userData['email'])) {
            throw new Exception("Name and email required");
        }
        if (!filter_var($userData['email'], FILTER_VALIDATE_EMAIL)) {
            throw new Exception("Invalid email");
        }

        // User creation logic mixed with persistence
        $query = "INSERT INTO users (name, email) VALUES (?, ?)";
        $stmt = $this->db->prepare($query);
        $stmt->execute([$userData['name'], $userData['email']]);

        // Sending emails directly in the method
        mail($userData['email'], ‘Welcome’, “Your account has been created”);

        return $this->db->lastInsertId();
    }
}

// Clean code reducing technical debt
class UserValidator {
    public function validate(array $userData): void {
        if (empty($userData['name']) || empty($userData['email'])) {
            throw new ValidationException("Name and email required");
        }
        if (!filter_var($userData['email'], FILTER_VALIDATE_EMAIL)) {
            throw new ValidationException("Invalid email");
        }
    }
}

class UserRepository {
    private $db;

    public function __construct(PDO $db) {
        $this->db = $db;
    }

    public function save(User $user): int {
        $query = "INSERT INTO users (name, email) VALUES (:name, :email)";
        $stmt = $this->db->prepare($query);
        $stmt->execute([':name' => $user->getName(), ':email' => $user->getEmail()]);
        return $this->db->lastInsertId();
    }
}

class EmailService {
    public function sendWelcomeEmail(string $email): void {
        // Email sending logic
    }
}

class UserManager {
    private $validator;
    private $repository;
    private $emailService;

    public function __construct(UserValidator $validator, UserRepository $repository, EmailService $emailService) {
        $this->validator = $validator;
        $this->repository = $repository;
        $this->emailService = $emailService;
    }

    public function createUser(array $userData): int {
        $this->validator->validate($userData);
        $user = new User($userData['name'], $userData['email']);
        $userId = $this->repository->save($user);
        $this->emailService->sendWelcomeEmail($user->getEmail());
        return $userId;
    }
}

Impact for developers:

1. Ease of maintenance: Developers can modify one part of the code without affecting others.
2. Better testability: Each component can be tested in isolation.
3. Increased reusability: Single-responsibility classes are more easily reusable in other parts of the project.
4. Easier to understand: The code is more readable and its structure is clearer.
5. Improved scalability: Adding new features becomes easier thanks to modularity.

Impact for decision-makers:

1. Long-term cost reduction: Less time spent understanding and modifying existing code.
2. Accelerated development: New features can be added more quickly.
3. Improved quality: Fewer bugs due to unforeseen changes.
4. Easier onboarding: New developers understand the code base faster.
5. Increased agility: The company can respond more quickly to market changes.
6. Reduced risk: Less reliance on specific individuals knowing complex parts of the code.

By investing in reducing technical debt through clean code practices, companies are not only making life easier for their developers; they are building a strong, flexible technology foundation that can quickly adapt to future opportunities and challenges. It’s a strategic investment that pays long-term dividends in productivity, quality, and innovation.

Article updated on August 30, 2024