Skip to main content

Building Block View Overview

Content​

The building block view shows the static decomposition of the BookWorm Store system into building blocks (services, components, modules, libraries, frameworks, etc.) as well as their dependencies and relationships.

This view is essential for understanding the system architecture and serves as the foundation for technical discussions and implementation decisions.

Motivation​

The building block view helps us:

  • Maintain system overview by making the structure understandable through abstraction
  • Enable effective communication with stakeholders on an architectural level without exposing implementation details
  • Support development teams by providing clear boundaries and interfaces between components
  • Facilitate system evolution by understanding dependencies and impact of changes
  • Guide deployment decisions by showing service boundaries and scaling units

Form​

The building block view is organized hierarchically across three levels:

Level 1: Glass Box Overall System​

Shows the highest level decomposition of the BookWorm Store into major building blocks:

  • Application Layer: Contains all business services and API gateway
  • Infrastructure Layer: Provides messaging, data persistence, and cross-cutting concerns
  • External Systems: Third-party integrations for authentication and notifications

This level provides the "big picture" view with the container diagram showing all services and their relationships.

Level 2: Detailed Service Decomposition​

Zooms into the most critical and complex services from Level 1:

  • Catalog Service: Product management, search, and inventory
  • Order Service: Order workflow and distributed transaction orchestration
  • Finance Service: Payment processing with security and compliance

Each service is decomposed into its internal components showing responsibilities and interfaces.

Level 3: Component Deep Dive​

Provides implementation details for the most complex components:

  • Saga Orchestrator: Distributed transaction management with compensation
  • Search Engine: AI-powered vector search implementation
  • Payment Processor: Secure transaction workflow with fraud detection

This level shows internal structure, algorithms, and design patterns used.

Each level builds upon the previous one, providing increasing detail while maintaining clear abstraction boundaries.