How One Team Rebuilt an E-commerce Platform Using 21 Golang Microservices and DDD

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A software engineering team migrated a monolithic e-commerce platform into a 21-service distributed system built with Golang and Domain-Driven Design to handle over 10,000 orders per day. The architecture uses the Kratos v2 framework to enforce Clean Architecture principles and maintain consistency across separate codebases. A core challenge was managing distributed transactions during checkout, which must synchronize asynchronously across Pricing, Warehouse, and Order services using a Saga orchestration pattern. Optimistic locking with versioned SQL queries is used to prevent race conditions when multiple requests compete for the same inventory. If any service in the checkout flow fails, a compensation mechanism automatically rolls back reserved stock using the original transaction ID.

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