What problem does it solve? Legacy Spring Boot codebases accumulate anti-patterns like scattered @Value fields, RestTemplate calls, hand-rolled retry loops, and anaemic services that are risky to change. This Skill provides safe, mechanical, test-preserving migration recipes so each refactor keeps the build green. ## Core Features & Use Cases - 15 step-by-step migrations: Covers @Value to @ConfigurationProperties records, if/else dispatch to Strategy + Handler, RestTemplate to RestClient with Resilience4j, anaemic services to DDD aggregates, @MockBean sprawl to @TestConfiguration boundary fakes, Hibernate auto-DDL to Flyway, and more. - Green-bar discipline: Every migration is sequenced so tests stay passing after each commit, with rules like one refactor per PR and behavior-pinning tests first. - Use Case: During a quality review you find a service with five @Value fields and a hand-rolled retry loop. Follow playbook sections 1 and 5 to introduce a properties record and Resilience4j @Retry, shipping each as a small reviewable PR. ## Quick Start Apply the refactoring playbook to migrate the RestTemplate calls in my FooService to a RestClient-based client with Resilience4j retry.
