Payment Gateways as Anti-Corruption Layers: Applying Hexagonal Architecture in Real-World PHP

Payment Gateways as Anti-Corruption Layers Most PHP applications integrate payments directly using provider SDKs. Example:\Stripe\Stripe::setApiKey($key); \Stripe\PaymentIntent::create([...]); This works. Until it doesn’t. The real architectural question isn’t how to charge a card. It’s: Should your domain know that Stripe exists? The Hidden Coupling Problem When business logic calls Stripe SDK directly, your domain layer now depends on: Stripe’s request models Stripe’s response objects Stripe’s exception types Stripe’s lifecycle semantics This is infrastructure bleeding into your core domain. And that’s where architecture begins to matter. Hexagonal Architecture Perspective In Hexagonal Architecture (Ports & Adapters): The Domain sits at the center. Infrastructure lives outside. Communication happens through defined ports. So the real question becomes: Should Stripe be inside the hexagon? The answer is no. Stripe is infrastructure. Introducing a Payment Port Instead of calling Stripe