From Spaghetti to Structure: Implementing the Repository Pattern in a 15-Year-Old PHP Monolith

The Mess We Inherited

AustinsElite (Legacy) has been running in production for 15 years. It’s a custom PHP MVC framework—long before Laravel was a thing—with a few Laravel components bolted on over time. When I started working on it, the data access logic was everywhere: controllers with raw SQL queries, cron scripts duplicating business rules, and magic strings scattered like confetti in conditionals.

Take event status handling. We had 'active', 'inactive', 'pending', 'cancelled'—all hardcoded across 10+ files. A typo? Welcome to silent failures. Want to add 'archived'? Good luck grepping your way through Blade templates, controllers, and artisan commands. And don’t get me started on the 300-line EventController that handled everything from rendering to database inserts.

This wasn’t just ugly—it was dangerous. Every change carried the risk of breaking something three layers down in a cron job no one remembered writing.

Enter Repositories (And a Little Dose of Sanity)

We didn’t rewrite the app. We couldn’t. But we could start carving out islands of clarity. The first move? Introduce the repository pattern to abstract data access and centralize business logic.

I started by creating EventRepository and UserRepository classes—plain PHP at first, no fancy interfaces (yet). These wrapped all database interactions for their respective domains. Instead of $db->select('events', ['status = ?', 'active']) in a controller, we now had $eventRepository->findActive().

Simple? Yes. Transformative? Absolutely.

Suddenly, the question "Where is active event logic defined?" had a one-line answer. No more grepping. No more guessing. And because these were dedicated classes, we could inject them—first manually, then via Laravel’s container where available—making testing and reuse trivial.

But the real win came with enums. We replaced every magic string for status fields with backed PHP enums:

enum EventStatus: string {
    case ACTIVE = 'active';
    case INACTIVE = 'inactive';
    case PENDING = 'pending';
    case CANCELLED = 'cancelled';
    case ARCHIVED = 'archived';
}

Now, instead of fragile strings, we had type-safe, IDE-autocompleted status checks. $status === 'actve' (typo intended) became $status === EventStatus::ACTIVE, caught at compile time. We even added helper methods:

public function isLive(): bool {
    return in_array($this, [self::ACTIVE, self::PENDING]);
}

This made business rules explicit—no more decoding intent from scattered conditionals.

Refactoring With Confidence

The real test came a week later: we needed to change how user roles were stored in the database. Pre-refactor, this would’ve been a 3-hour grep-and-pray session. Post-refactor? We updated the UserRepository’s persistence logic, adjusted the enum, ran tests, and deployed.

Because all data access flowed through a single abstraction, we could change the underlying schema without touching controllers or views. The boundaries were clear. The risk was low.

This wasn’t just about cleaner code—it was about sustainable code. New developers could now understand the flow of data without memorizing the entire app. Business logic lived where it belonged: in domain-specific services, not in HTTP handlers.

And yes, we kept it pragmatic. No hexagonal architecture diagrams. No service buses. Just repositories, enums, and a commitment to leaving the codebase better than we found it.

If you’re neck-deep in a legacy PHP monolith, here’s my advice: don’t wait for a rewrite. Start small. Pick one domain. Extract one repository. Replace one set of magic strings with an enum. You’ll gain clarity—and confidence—one commit at a time.

The refactor on December 7th wasn’t flashy, but it was foundational. And for a 15-year-old codebase, that’s exactly what we needed.