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+# ADR for Payment Boundary
+
+## Context
+This document provides the Architectural Decision Record (ADR) for defining the payment boundary within the project's architecture. The objective is to create a clear demarcation of responsibilities related to payment processing, ensuring that all payment-related functionalities are encapsulated and modular.
+
+## Decision
+We have decided to adopt a microservices architecture for the payment processing functionality. The payment service will handle all interactions related to payment transactions, including validation, processing, and integration with third-party payment providers.
+
+## Alternatives
+1. **Monolithic Architecture**: We could have developed the payment processing functionality as a part of the existing monolithic application. However, this would lead to tight coupling and reduced scalability.
+2. **Serverless Architecture**: Another alternative was to implement the payment service using serverless functions. This would provide ease of scaling but at the cost of increased complexity in managing state and transactions.
+
+## Consequences
+By selecting a microservices architecture, we ensure scalability and flexibility in deploying updates to the payment service independently. However, this approach may introduce challenges related to inter-service communication and require robust monitoring and logging mechanisms to track payment transaction flows.
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