Payment service
Owns logical operations and recorded state
Use cases
- Pay for the €100 lamp 2 steps
The service records, submits and resolves one logical payment. · Checkout reads what is known; a missing answer remains visibly unknown.
- Refund the unavailable lamp 2 steps
Support checks the confirmed payment and its existing refund history. · Support requests a separate refund; the service records its request and compatible processor confirmation.