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Dariusz Gafka
Dariusz Gafka

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Your Legacy PHP Codebase Isn't Hopeless

#architecture #backend #codequality #php

You ship a small bug fix. Suddenly, two other features break. Every deployment feels like gambling. The business depends on this app — it brings in revenue, customers use it daily — but nobody feels confident working on it.

You open a file that should be a simple list of functions and find a 2,000‑line monolith of nested loops and if‑statements. Comments like // Temporary fix from years before. Presentation, database queries, and business logic all mixed together in what one developer described as a “glorious spaghetti mashup.”

You're not alone. And your codebase isn't hopeless.

The Industry’s Dirty Secret

  • ~13% of Composer installs still run end‑of‑life PHP versions
  • ~27% are on EOL or security‑only versions
  • Over 50% of popular PHP packages support unsupported PHP versions

Legacy systems are the norm, not the exception.

The Trap: Rewrite or Suffer

  • Rewrites have ~23% success rate
  • Incremental modernization has ~53% success rate
  • Small changes fail only ~4% of the time

Rewrites discard years of encoded business knowledge.

The Third Path: Incremental Transformation

Instead of rewriting everything:

  1. Identify a painful area
  2. Extract logic into a message handler
  3. Test it in isolation
  4. Make it async if needed
  5. Repeat

This is exactly what Ecotone enables.

Example: The 800‑Line Controller 

class OrderController
{
    public function placeOrder(Request $request)
    {
        // validation, persistence, payments, emails, analytics...
    }
}
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Step 1: Extract an Event 

class OrderWasPlaced
{
    public function __construct(
        public string $orderId,
        public string $customerId,
        public float $total
    ) {}
}
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class OrderNotificationHandler
{
    #[EventHandler]
    public function sendConfirmation(OrderWasPlaced $event): void {}
}
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Step 2: Publish From Legacy Code 

$this->eventBus->publish(new OrderWasPlaced(
    $order->id,
    $customer->id,
    $order->total
));
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Step 3: Test in Isolation 

class OrderNotificationHandlerTest extends TestCase {}
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Step 4: Make It Async 

#[Asynchronous('notifications')]
#[EventHandler]
public function sendConfirmation(OrderWasPlaced $event): void {}
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Step 5: Repeat

Analytics, loyalty points, reporting — each becomes isolated and testable.

Command Handlers 

class PlaceOrder {}
class OrderHandler {}
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$this->commandBus->send(new PlaceOrder(...));
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Database Queries 

interface OrderQueries
{
    #[DbalQuery(...)]
    public function getPendingOrders(string $customerId): array;
}
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Resilience & Retries

Retries, DLQs, and error handling are declarative and consistent.

Idempotency 

#[Deduplicated('orderId')]
#[CommandHandler]
public function placeOrder(PlaceOrder $command): string {}
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Why This Works

  • System keeps running
  • Small PRs
  • Fast tests
  • Compounding improvements
  • Attracts senior engineers

Getting Started 

composer require ecotone/ecotone
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Laravel and Symfony integrations available.

Conclusion

Legacy codebases are not failures — they are assets.
Incremental modernization gives them a future.

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