This roadmap is designed by a Spring Boot developer with 10+ years of experience. It focuses solely on Spring Boot and related Spring ecosystem modules, divided by years of experience. Ideal for anyone preparing for Spring-based job roles.

🌟 0–1 Years Experience: Spring Boot for Freshers / Beginners

🔗 Goal: Understand the fundamentals of Spring Boot and its ecosystem.

1. Java Pre-requisites (Quick Recap)

• OOPs, Exception Handling, Generics
• Java 8+ Features (Lambdas, Streams, Functional Interfaces)

2. Spring Core Basics

• Inversion of Control (IoC)
• Dependency Injection (DI)
• ApplicationContext vs BeanFactory
• Bean Scopes and Lifecycle

3. Spring Boot Basics

• What is Spring Boot and its advantages
• Spring Boot Starter Projects
• Auto-Configuration
• application.properties vs application.yml
• Profiles in Spring Boot

4. Spring Boot REST API Development

• @RestController, @RequestMapping, @GetMapping, @PostMapping
• Request Parameters, Path Variables
• ResponseEntity and Custom Responses

5. Spring Boot Validation

• JSR-380 (Bean Validation API)
• @Valid and @Validated
• Custom Validation Annotations

6. Spring Boot with JPA (Spring Data JPA)

• Entity, Repository, CrudRepository, JpaRepository
• Derived Query Methods
• @OneToOne, @OneToMany, @ManyToOne
• DTO vs Entity vs Projection

7. In-Memory Databases

• H2 / HSQL Integration
• application.yml configuration

8. Basic Testing

• @SpringBootTest
• MockMvc
• Unit Testing with JUnit5

🔼 1–3 Years Experience: Junior Spring Boot Developer

🔗 Goal: Master CRUD APIs, layered architecture, and real-world integrations.

1. REST API Best Practices

• Status Codes
• Exception Handling using @ControllerAdvice
• Standardized Response Format

2. Layered Architecture

• Controller > Service > Repository
• DTO and Mapper (MapStruct or manual mapping)
• ModelMapper usage

3. Database & Spring Data JPA

• Pagination & Sorting
• Custom Queries (@Query, nativeQuery)
• Specifications / Criteria API
• Transaction Management (@Transactional)

4. Spring Boot Testing

• Mockito for mocking
• @WebMvcTest, @DataJpaTest
• Integration Testing

5. Configuration Management

• YAML vs Properties
• Profile-specific configs
• Environment Variables and External Configuration

6. Dev Tools & Logs

• Spring Boot DevTools
• Logging (SLF4J, Logback)
• Log Levels per environment

7. Swagger & Postman

• OpenAPI 3 with springdoc-openapi-ui
• Generating API docs
• Postman Collections for testing APIs

8. Actuator Basics

• Health, Metrics, Info endpoints
• Securing actuator endpoints

🔽 3–5 Years Experience: Mid-Level Spring Boot Developer

🔗 Goal: Build production-grade services with security, monitoring, and caching.

1. Spring Security

• Basic Authentication
• JWT (JSON Web Token) Integration
• OAuth2 Basics
• Custom Filters

2. Caching in Spring Boot

• @Cacheable, @CacheEvict
• In-memory cache with ConcurrentMap
• Integrate Redis or Ehcache

3. Exception Handling (Advanced)

• Custom Exception Hierarchy
• Problem Details Format (RFC 7807)

4. Spring Boot Actuator (Advanced)

• Custom Health Indicators
• Micrometer Integration
• Exposing custom metrics

5. API Versioning

• URI-based, Header-based versioning

6. File Upload / Download

• MultipartFile support
• Streaming large files

7. Async Programming

• @Async and AsyncConfigurer
• CompletableFuture with Spring

🔽 5–7 Years Experience: Senior Spring Boot Developer

🔗 Goal: Build scalable, resilient, and enterprise-ready solutions.

1. Advanced Spring Security

• Method-level Security
• Custom Authentication Provider
• SecurityContext Handling

2. Microservices with Spring Boot

• Introduction to Microservices Architecture
• Communication using REST + Feign Client
• API Gateway (Spring Cloud Gateway basics)
• Eureka for Service Discovery

3. Spring Cloud Config

• Centralized Configuration
• Git-backed Configuration Repo
• Refresh Scope and Bus

4. Observability & Monitoring

• Distributed Tracing with Zipkin
• Logging Correlation IDs
• Micrometer + Prometheus + Grafana

5. Resilience4j

• Circuit Breaker, Retry, Rate Limiter
• Integration with Feign Clients

6. Scheduling & Task Execution

• @Scheduled tasks
• ThreadPoolTaskScheduler

7. Advanced Testing

• TestContainers for Integration
• MockBeans
• CI Integration with Spring Boot Tests

🌟 7+ Years Experience: Spring Boot Architect / Expert

🔗 Goal: Design robust architectures, frameworks, and reusability layers.

1. Custom Starters

• Build reusable starters for internal libraries

2. Modular Monolith & Hexagonal Architecture

• Layer separation and port-adapter pattern

3. Spring Cloud Advanced

• Spring Cloud Bus, Sleuth, Config
• Kafka with Spring Cloud Stream

4. Reactive Programming with Spring WebFlux

• Mono, Flux, Reactive Repositories
• Backpressure handling

5. Native Compilation (Spring Boot 3 + GraalVM)

• Build native images
• Startup performance tuning

6. Advanced CI/CD Integration

• GitHub Actions, Jenkins Pipelines
• Spring Profiles for deployment

7. API Governance

• Shared response models, standard versioning policies
• API contracts with consumers

📆 Final Thoughts

This roadmap is designed to help Java developers grow from freshers to Spring Boot architects by focusing purely on Spring-related technologies. Each phase builds on the previous one, ensuring solid foundations and advanced specializations in REST, microservices, and cloud-native Spring Boot development.

✅ Whether you’re just starting out or preparing for senior interviews, this Spring Boot roadmap keeps you aligned with modern enterprise requirements in 2025 and beyond.