A Spring Boot Project That Is Easy to Run and Review

A reviewer opens a repository, reads the first page and tries to start the application. If that requires guessing the Java version, installing an undocumented database and fixing missing configuration, the review begins with friction.

A small project does not need elaborate infrastructure. It needs an obvious path from a fresh clone to a working request, followed by a clear explanation of what the project demonstrates.

State what the reviewer needs

Start the README with exact requirements. Distinguish the tools used to build the application from the tools needed to run its dependencies.

For a typical local setup, that means a compatible JDK and a Docker engine with Compose if the database runs in a container. The first build may need network access to download Maven, dependencies and the database image. Include the Windows commands where they differ from the Unix commands.

The examples below assume an existing Spring Boot project with Maven Wrapper, a REST endpoint, JDBC-based persistence and a PostgreSQL driver. They show how to package and document it; they are not a complete application repository.

Commit the Maven Wrapper

Provide mvnw, mvnw.cmd and the appropriate wrapper files under .mvn/wrapper. Make the Unix script executable in Git. This gives the project a defined Maven version and avoids requiring a separate Maven installation.

./mvnw verify
./mvnw spring-boot:run -Dspring-boot.run.profiles=local

On Windows, use mvnw.cmd instead. The wrapper downloads its configured Maven distribution when necessary; it does not supply the project’s JDK. The behaviour and configuration are documented by Apache Maven Wrapper.

Containerise the database first

Running PostgreSQL in Docker while running Java on the host is a useful default. The reviewer can debug the application in an IDE without also maintaining a local database installation.

A minimal compose.yaml for an isolated local demo could be:

services:
  db:
    image: postgres:17
    environment:
      POSTGRES_DB: demo
      POSTGRES_USER: demo
      POSTGRES_PASSWORD: demo
    ports:
      - "127.0.0.1:5432:5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U demo -d demo"]
      interval: 5s
      timeout: 5s
      retries: 10
      start_period: 10s
    volumes:
      - demo-data:/var/lib/postgresql/data

volumes:
  demo-data:

The credentials are disposable local defaults. A published deployment should use its own configuration. The 17 tag selects a major version but can change to a later patch; use a verified digest when exact image reproducibility is required.

Configure the corresponding application-local.yaml:

spring:
  datasource:
    url: ${DB_URL:jdbc:postgresql://localhost:5432/demo}
    username: ${DB_USER:demo}
    password: ${DB_PASSWORD:demo}

These hostnames assume Java runs on the host. If the application also runs inside Compose, localhost refers to its own container; configure the database hostname as db instead.

Start the database and wait for its health check:

docker compose up -d --wait

Check that the installed Compose version supports --wait. A running container is not necessarily ready to accept connections, which is why the health check matters. See Docker’s startup-order guide and Compose up reference.

Make the database repeatable

Include versioned schema migrations and a small, predictable set of demo data. A reviewer should not need to execute SQL manually before the first request.

If the project uses Flyway, include the dependencies required by its Boot line and PostgreSQL support. Avoid relying on Hibernate schema generation as the only description of a schema whose migration behaviour you want to demonstrate. Spring Boot’s SQL database documentation provides the configuration reference.

For unit tests that do not use persistence, a database should not be necessary. For integration tests involving PostgreSQL-specific SQL or semantics, test against PostgreSQL rather than assuming an in-memory database is equivalent.

Give the reviewer a first request

The README should include a working command and its expected response. For example, a project exposing GET /api/products should show a curl request and the deterministic sample products created by its demo dataset. Do not document an endpoint that the project does not implement.

If Actuator is included and its health endpoint is available, this is a useful initial check:

curl -f http://localhost:8080/actuator/health

Describe any authentication needed. Health checks are useful, but a successful health response is not a substitute for exercising the main API.

Explain the limits and cleanup

Document occupied ports, how to change configuration and how to stop the database:

docker compose down

With the named volume above, this preserves the stored demo data. If you also provide a reset command, label it clearly as deleting that data rather than presenting it as ordinary shutdown.

A small example can show good engineering through clear boundaries, useful tests and a repeatable setup. The reviewer should spend their time examining those choices, not reconstructing the environment that made the project work on the author’s laptop.