Spring Boot Service taste

# Spring Boot Service taste of a pragmatic Java backend engineer
- Start on the latest Spring Boot release with a current Java LTS version, and enable virtual threads where blocking I/O dominates. Confidence: 0.80
- Organize packages by feature such as orders or billing rather than by layer like controllers, services and repositories. Confidence: 0.85
- Use constructor injection with final fields everywhere and never field injection with @Autowired. Confidence: 0.95
- Bind configuration to typed, validated @ConfigurationProperties records instead of scattered @Value strings. Confidence: 0.90
- Keep secrets out of application.yml and read them from environment variables or a secrets manager. Confidence: 0.95
- Use Java records for request and response DTOs and keep JPA entities out of controller signatures. Confidence: 0.90
- Validate requests with Bean Validation annotations and @Valid, and return ProblemDetail responses for every error. Confidence: 0.85
- Handle exceptions in one @RestControllerAdvice class instead of try/catch blocks in each controller. Confidence: 0.85
- Put @Transactional on service methods, keep transactions short, and never call remote services inside one. Confidence: 0.90
- Turn off open-in-view and fetch associations explicitly with fetch joins or entity graphs to avoid N+1 queries. Confidence: 0.90
- Manage schema changes with Flyway or Liquibase migrations and keep Hibernate ddl-auto set to validate or none. Confidence: 0.95
- Call other HTTP services through RestClient or declarative HTTP interfaces with explicit connect and read timeouts. Confidence: 0.85
- Wrap unreliable dependencies in retries with backoff and circuit breakers, and make retried operations idempotent. Confidence: 0.80
- Log in structured JSON with correlation IDs from tracing, and never log tokens, passwords or full request bodies. Confidence: 0.90
- Expose only health, info and metrics Actuator endpoints publicly, and secure or disable the rest. Confidence: 0.90
- Export metrics and traces with Micrometer and OpenTelemetry instead of custom timing code. Confidence: 0.80
- Secure endpoints with Spring Security as an OAuth2 resource server and method-level authorization for sensitive actions. Confidence: 0.85
- Write fast slice tests with @WebMvcTest and @DataJpaTest, and keep full @SpringBootTest runs for a few key flows. Confidence: 0.80
- Run integration tests against real databases and brokers in Testcontainers rather than H2 or embedded fakes. Confidence: 0.90
- Generate the OpenAPI spec from code with springdoc and publish it with every build. Confidence: 0.70
- Build container images with Buildpacks or layered jars and run them as a non-root user with memory limits set. Confidence: 0.80
- Keep dependency versions managed by the Spring Boot BOM and let a bot like Renovate open upgrade pull requests. Confidence: 0.80