Stop Writing CRUD APIs: 5 Advanced Spring Boot Patterns That Impress in Code Reviews

Basic CRUD gets you hired. These advanced patterns get you promoted. Learn what code reviewers actually want to see.

I’ll never forget my first code review as a junior developer. I was proud of my Spring Boot API — it worked perfectly, had all the CRUD endpoints, and the tests passed. Then my senior colleague left this comment: “This works, but it’s not production-ready. Real applications need patterns that handle complexity, not just database operations.”

That comment changed how I write Spring Boot applications. Today, I’ll share the five patterns that transformed my code from “it works” to “this is impressive.”

The Problem with Basic CRUD

Most Spring Boot tutorials teach you this:

@RestController
@RequestMapping("/api/users")
public class UserController {
@Autowired
    private UserRepository userRepository;
@PostMapping
    public User createUser(@RequestBody User user) {
        return userRepository.save(user);
    }
@GetMapping("/{id}")
    public User getUser(@PathVariable Long id) {
        return userRepository.findById(id).orElseThrow();
    }
}

This code has serious problems:

• No separation…