Session Name: Project Horizon: Enterprise .NET Microservices Masterclass
Step-by-Step Architecture Roadmap
Building a production-grade, event-driven e-commerce platform implementing CQRS (Command Query Responsibility Segregation) and the Saga Pattern (for distributed transactions) provides an exceptional architectural blueprint for senior-level engineering interviews.
The step-by-step master plan unfolds through these core phases:
Phase 1: Solution Structure & Domain Modeling (CQRS Foundation)
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Set up a clean Solution folder structure following Clean Architecture principles (Domain, Application, Infrastructure, Presentation).
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Define core e-commerce aggregates: Products, Orders, Customers, and Payments.
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Implement the MediatR library to decouple write operations (Commands) from read models (Queries).
Phase 2: Distributed Messaging & Event Broker (RabbitMQ / LocalStack SNS-SQS)
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Configure local message bus infrastructure using Docker Compose alongside your LocalStack and database containers.
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Implement event publishers and consumers for cross-service communication (e.g.,
OrderCreatedEvent,PaymentProcessedEvent).
Phase 3: The Saga Pattern (Orchestration vs. Choreography)
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Build a Distributed Saga Coordinator to manage the checkout lifecycle.
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Implement compensating transactions (rollbacks) for failure scenarios—such as automatically releasing reserved inventory if a payment gateway transaction declines.
Phase 4: API Gateway, Rate Limiting & Security
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Implement a reverse proxy / API Gateway layer (such as Ocelot or YARP) to route client requests to underlying microservices.
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Integrate JWT-based authentication and role-based access control (RBAC).
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Configure distributed rate limiting (using Redis) to prevent endpoint abuse and protect downstream services.
Phase 5: Observability, Resilience & Polish
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Implement circuit breakers and retry logic (using Polly) for resilient inter-service HTTP and messaging calls.
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Add structured logging and distributed tracing so requests can be tracked seamlessly across service boundaries.
This session is saved and fully contextualized. Whenever you have free time, just return to this chat, and we can begin executing Phase 1 step by step.