Build a Spring Boot REST Microservice (Java, JPA, Postgres, Docker)
Track: Java / Backend
Java is the single most-hired-for backend skill on the enterprise board — and Spring Boot is how almost all of it ships. A clean REST microservice with a database, validation, tests, and a Dockerfile is the project that gets a junior Java résumé past the screen. This is that project.
What you’ll build: a Spring Boot REST microservice backed by a relational database via Spring Data JPA — layered controller/service/repository code, bean validation, JUnit tests, and a Dockerfile. Pick any resource to manage (items, books, tickets); the Spring fundamentals are the point. This is the synchronous-REST counterpart to the event-driven Kafka project — build both to show range.
Enterprise Java interviews assume Spring. A microservice that demonstrates dependency injection, JPA persistence, validation, and tests proves you can be productive in their stack on day one. It maps to the keywords these roles list: Java, Spring Boot, Spring Data JPA, REST API, PostgreSQL, Maven, JUnit, microservices, Hibernate.
Skills & keywords you’ll demonstrate
Spring Boot — dependency injection, auto-configuration, layered architecture
Spring Data JPA / Hibernate persistence against PostgreSQL
A REST API with proper status codes and bean validation
JUnit + Spring Boot tests (MockMvc / @DataJpaTest)
Maven build and a Dockerfile (multi-stage build → slim JRE)
Starter repo
Clone github.com/OptimalMatch/resume-project-java-spring-microservices — a Maven layout with an entity, repository, controller, a test stub, and a Dockerfile; H2 is wired so it runs before you connect Postgres. Build it under your own account, committing per milestone.
Build it in milestones
Boot it up. Run the Spring Boot app and hit a health endpoint. Commit.
Model + persistence. Define your @Entity and a JpaRepository; let it create the table. Commit.
REST CRUD. Controller endpoints for create/read/update/delete, returning proper status codes. Commit.
Validation & errors. Bean validation on inputs and a handler that returns structured errors for bad requests and missing records. Commit.
Tests. JUnit tests for the controller and repository (MockMvc, @DataJpaTest). Commit.
Postgres + Docker. Swap H2 for PostgreSQL via config; add a Dockerfile and run it in a container. Commit.
Stretch goals
OpenAPI/Swagger docs via springdoc.
Pagination, sorting, and filtering on the list endpoint.
Spring Security with JWT on write endpoints; a CI workflow that runs mvn test.
Put it on your résumé
“Built a Spring Boot REST microservice with Spring Data JPA persistence to PostgreSQL, bean validation, and layered controller/service/repository architecture.”
“Covered it with JUnit and Spring Boot tests and packaged it with a multi-stage Docker build.”
Update your résumé and check it with the free ATS resume score — enterprise Java roles weight exactly these keywords.
Frequently asked questions
Why Spring Boot for a junior Java résumé? Spring Boot is the default framework for enterprise Java hiring. A microservice that shows dependency injection, JPA persistence, validation, and tests proves you can be productive in the exact stack most Java teams use — far more than language syntax alone.
How is this different from the Kafka order-service project? This one is a synchronous REST microservice (request in, response out, backed by a database). The Kafka project is event-driven/asynchronous messaging. Building both shows range — most enterprise Java teams do both, and the two together cover the bulk of Java job postings.