Building microservices requires more than splitting a monolith into services. You need service discovery, a gateway to route traffic, centralised configuration management, and resilience patterns to handle inevitable failures. Spring Cloud provides all of this as a cohesive stack. This guide builds a complete microservices architecture from scratch: Eureka for service discovery, Spring Cloud Gateway for routing, Spring Cloud Config Server for centralised config, and Resilience4j for circuit breakers and retry.