Stripe Integration for PHP Applications

Plain PHP projects — not built on Laravel or another framework — need the Stripe PHP SDK integrated directly, which is common for legacy applications, custom CMS-adjacent codebases, and internal tools that predate a framework decision or deliberately avoid one.

Framework-Free Integration Considerations

• Webhook signature verification via the SDK's `Webhook::constructEvent` against the raw request body, same principle as any framework but without middleware to fight
• Composer-based dependency management even in otherwise framework-free codebases, to keep the Stripe SDK and its dependencies current
• Session and state handling for multi-step checkout flows needs to be built explicitly, since there's no framework convention to lean on
• PHP 8+ is our recommended baseline for new work — legacy PHP 7.x projects are supported, but with an eye toward an upgrade path

Framework-free doesn't mean unstructured — we still separate Stripe API calls, webhook handling, and business logic into distinct layers, just without a framework enforcing that separation for you. It's more discipline required, not less integration quality possible.