spring-boot-saga-pattern

This skill implements the Saga Pattern for distributed transactions across Spring Boot microservices. It solves a core problem in service-oriented architectures: a business process spanning multiple services cannot use a single ACID transaction, and two-phase commit (2PC) scales poorly. The Saga Pattern replaces 2PC with a sequence of local transactions, each paired with a compensating action that undoes it if a later step fails, achieving eventual consistency.

The skill supports both choreography (event-driven, using Spring Cloud Stream with Kafka or RabbitMQ) and orchestration (a centralized coordinator, using Axon Framework, Eventuate Tram, or Camunda), with guidance on choosing between them based on system complexity and team expertise. It walks through designing the transaction flow and its compensations, implementing services with local ACID transactions that publish events, building idempotent compensating transactions, configuring message brokers with idempotent consumers, and implementing a saga orchestrator. An extensive set of reference files covers compensating transactions, event-driven architecture, orchestration and choreography implementation, state management, error handling and retry, testing strategies, common pitfalls, and worked examples (order/payment/inventory/shipment flows).

The target users are Java microservices architects and backend engineers building distributed systems who need reliable rollback semantics across service boundaries. Use cases include e-commerce order processing, payment and refund flows, inventory reservation and release, and any long-running business process that must remain consistent when an individual step fails.