APIs evolve. Adding fields is safe — removing or changing fields breaks clients. Versioning gives you a path to evolve the API without breaking existing integrations. When You Need Versioning You need a new API version when: Removing a field from a response Changing a field’s type or semantics Changing URL structure significantly Breaking backward-incompatible business logic changes You don’t need a new version for: Adding new optional fields (non-breaking) Adding new endpoints Bug fixes that don’t change the contract Strategy 1: URL Path Versioning The most common and explicit approach:

Time to build something real. In this article you’ll create a fully functional REST API for the order-service — create, read, update, and delete orders over HTTP. Project Setup Start with these dependencies at start.spring.io: <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-validation</artifactId> </dependency> spring-boot-starter-web includes: Embedded Tomcat (no WAR deployment needed) Spring MVC (the web framework) Jackson (JSON serialization) The Request Processing Pipeline Before writing code, understand how Spring MVC handles a request: