spring-boot-fallback

# Spring Boot Fallback ## Overview Quarkus is the default (see quarkus-service-architecture). Spring Boot is the fallback — reach for it only when Quarkus genuinely does not fit. The architecture is the same clean layering; only the annotations and container differ. **Core principle:** Same layered design as Quarkus. Spring is a container choice, not a license to sprawl. ## When Spring Boot instead of Quarkus - The repository already uses Spring Boot — follow it. - A required library/integration has no Quarkus extension and no clean CDI alternative. - The deployment target or team standard mandates Spring. If none of these hold, use Quarkus. ## Layer mapping (same responsibilities, Spring surface) | Layer | Quarkus | Spring Boot | |-------|---------|-------------| | Resource/Controller | JAX-RS `@Path` | `@RestController` `@RequestMapping` | | Service | `@ApplicationScoped` | `@Service` | | Repository | Panache | `JpaRepository` (Spring Data) | | Validation | `@Valid` + Bean Validation | `@Valid` + Bean Validation | | Config | `@ConfigProperty` | `@ConfigurationProperties` / `@Value` | | Transaction | `@Transactional` (service) | `@Transactional` (service) | ## Patterns (identical discipline) - **Constructor injection only** — Spring injects a single constructor automatically; no `@Autowired` on fields. - **DTOs (records) at the controller edge**; never return JPA entities from a controller. - **Bean Validation** on request DTOs, `@Valid` on the controller method. -...