diff --git a/.forge/SPRING-ARC-REF-FINAL-1783833422-attempt-2.md b/.forge/SPRING-ARC-REF-FINAL-1783833422-attempt-2.md
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+# SPRING-ARC-REF-FINAL-1783833422-attempt-2
+
+Forge 이슈 작업 브랜치 `forge/SPRING-ARC-REF-FINAL-1783833422-attempt-2`.
diff --git a/docs/architecture/adr-payment-boundary.md b/docs/architecture/adr-payment-boundary.md
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+# ADR for Payment Boundary
+
+## Context
+The payment processing system is pivotal for the business operations, therefore a well-defined boundary is necessary to manage dependencies, isolate services, and ensure the resilience of the application.
+
+## Decision
+We will implement a microservices architecture for payment processing, with the following boundaries: 1. Payment Service, 2. Notification Service, 3. Reporting Service. These services will communicate through well-defined APIs and will be independently deployable. 
+
+## Alternatives
+1. Monolithic architecture - rejected due to tight coupling and scalability issues.
+2. Service-oriented architecture - rejected due to complexity in service integrations compared to microservices.
+
+## Consequences
+This decision allows for better scalability and maintainability of the payment processing system but will introduce challenges in inter-service communication and data consistency management.
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diff --git a/docs/architecture/package-map.md b/docs/architecture/package-map.md
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+| 패키지       | 책임                          | 금지 의존성         |
+|--------------|-------------------------------|---------------------|
+| controller    | 사용자 요청 처리               | service, repository  |
+| service       | 비즈니스 로직 처리             | controller           |
+| repository    | 데이터 접근 및 관리            | service              |
+| domain        | 도메인 모델 및 규칙 정의      | integration          |
+| integration    | 외부 시스템과의 통신 처리      | domain               |
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diff --git a/docs/architecture/transaction-sequence.md b/docs/architecture/transaction-sequence.md
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+```mermaid
+sequenceDiagram
+    participant User
+    participant Controller
+    participant Service
+    participant Repository
+    participant Database
+
+    User->>Controller: 결제 요청
+    Controller->>Service: 결제 처리 요청
+    Service->>Repository: 결제 정보 저장
+    Repository->>Database: DB에 저장
+    Database-->>Repository: 저장 완료
+    Repository-->>Service: 저장 완료
+    Service-->>Controller: 처리 완료
+    Controller-->>User: 결제 완료
+
+    %% 외부 실패 흐름
+    User->>Controller: 결제 요청
+    Controller->>Service: 결제 처리 요청
+    Service->>Repository: 결제 정보 저장
+    Repository->>Database: DB에 저장
+    Database-->>Repository: 저장 실패
+    Repository-->>Service: 저장 실패
+    Service-->>Controller: 처리 실패
+    Controller-->>User: 결제 실패
+
+    %% DB 실패 흐름
+    User->>Controller: 결제 요청
+    Controller->>Service: 결제 처리 요청
+    Service->>Repository: 결제 정보 저장
+    Repository->>Database: DB에 저장
+    Database-->>Repository: DB 오류
+    Repository-->>Service: DB 오류
+    Service-->>Controller: 처리 실패
+    Controller-->>User: 결제 실패
+
+    %% Commit/Rollback 경계
+    alt 정상 흐름
+        Service->>Database: Commit
+    else 외부 실패
+        Service->>Database: Rollback
+    else DB 실패
+        Service->>Database: Rollback
+    end
+```
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