Spring Boot Project Creator

Overview

Generates a fully configured Spring Boot project from scratch using the Spring Initializr API. The skill walks the user through selecting project parameters, choosing an architecture style (DDD or Layered), configuring data stores, and setting up Docker Compose for local development. The result is a build-ready project with standardized structure, dependency management, and configuration.

When to Use

Bootstrap a new Spring Boot 3.x or 4.x project with a standard structure.
Initialize a backend microservice with JPA, SpringDoc OpenAPI, and Docker Compose.
Scaffold a project following either DDD (Domain-Driven Design) or Layered (Controller/Service/Repository/Model) architecture.
Set up local development infrastructure with PostgreSQL, Redis, and/or MongoDB via Docker Compose.
Trigger phrases: "create spring boot project", "new spring boot app", "bootstrap java project", "scaffold spring boot microservice", "initialize spring boot backend", "generate spring boot project".

Prerequisites

Before starting, ensure the following tools are installed:

Java Development Kit (JDK): Version 17+ (Java 21 recommended for Spring Boot 3.x/4.x)
Apache Maven: Build tool (Spring Initializr generates Maven projects by default)
Docker and Docker Compose: For running local infrastructure services
curl and unzip: For downloading and extracting the project from Spring Initializr

Instructions

Follow these steps to create a new Spring Boot project.

1. Gather Project Configuration

Ask the user for the following project parameters using AskUserQuestion. Provide sensible defaults:

Parameter	Default	Options
Group ID	`com.example`	Any valid Java package name
Artifact ID	`demo`	Kebab-case identifier
Package Name	Same as Group ID	Valid Java package
Spring Boot Version	`3.4.5`	`3.4.x` , `4.0.x` (check start.spring.io for latest)
Java Version	`21`	`17` , `21`
Architecture	User choice	`DDD` or `Layered`
Docker Services	User choice	PostgreSQL, Redis, MongoDB (multi-select)
Build Tool	`maven`	`maven` , `gradle`

2. Generate Project with Spring Initializr

Use

curl

to download the project scaffold from start.spring.io.

Base dependencies (always included):

```
web
```
— Spring Web MVC
```
validation
```
— Jakarta Bean Validation
```
data-jpa
```
— Spring Data JPA
```
testcontainers
```
— Testcontainers support

Conditional dependencies (based on Docker Services selection):

PostgreSQL selected → add
```
postgresql
```
Redis selected → add
```
data-redis
```
MongoDB selected → add
```
data-mongodb
```

bash

# Example for Spring Boot 3.4.5 with PostgreSQL only
curl -s https://start.spring.io/starter.zip \
  -d type=maven-project \
  -d language=java \
  -d bootVersion=3.4.5 \
  -d groupId=com.example \
  -d artifactId=demo \
  -d packageName=com.example \
  -d javaVersion=21 \
  -d packaging=jar \
  -d dependencies=web,data-jpa,postgresql,validation,testcontainers \
  -o starter.zip

unzip -o starter.zip -d ./demo
rm starter.zip
cd demo

3. Add Additional Dependencies

Edit

pom.xml

to add SpringDoc OpenAPI and ArchUnit for architectural testing.

xml

<!-- SpringDoc OpenAPI -->
<dependency>
    <groupId>org.springdoc</groupId>
    <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
    <version>2.8.15</version>
</dependency>

<!-- ArchUnit for architecture tests -->
<dependency>
    <groupId>com.tngtech.archunit</groupId>
    <artifactId>archunit-junit5</artifactId>
    <version>1.4.1</version>
    <scope>test</scope>
</dependency>

4. Create Architecture Structure

Based on the user's choice, create the package structure under

src/main/java/<packagePath>/

Option A: Layered Architecture

src/main/java/com/example/
├── controller/        # REST controllers (@RestController)
├── service/           # Business logic (@Service)
├── repository/        # Data access (@Repository, Spring Data interfaces)
├── model/             # JPA entities (@Entity)
│   └── dto/           # Request/Response DTOs (Java records)
├── config/            # Configuration classes (@Configuration)
└── exception/         # Custom exceptions and @ControllerAdvice

Create placeholder classes for each layer:

config/OpenApiConfig.java — SpringDoc OpenAPI configuration bean
exception/GlobalExceptionHandler.java —
```
@RestControllerAdvice
```
with standard error handling
model/dto/ErrorResponse.java — Standard error response record

Option B: DDD (Domain-Driven Design) Architecture

src/main/java/com/example/
├── domain/                 # Core domain (framework-free)
│   ├── model/              # Entities, Value Objects, Aggregates
│   ├── repository/         # Repository interfaces (ports)
│   └── exception/          # Domain exceptions
├── application/            # Use cases / Application services
│   ├── service/            # @Service orchestration
│   └── dto/                # Input/Output DTOs (records)
├── infrastructure/         # External adapters
│   ├── persistence/        # JPA entities, Spring Data repos
│   └── config/             # Spring @Configuration
└── presentation/           # REST API layer
    ├── controller/         # @RestController
    └── exception/          # @RestControllerAdvice

Create placeholder classes for each layer:

infrastructure/config/OpenApiConfig.java — SpringDoc OpenAPI configuration bean
presentation/exception/GlobalExceptionHandler.java —
```
@RestControllerAdvice
```
with standard error handling
application/dto/ErrorResponse.java — Standard error response record

5. Configure Application Properties

Create

src/main/resources/application.properties

with the selected services.

Always include:

properties

# Application
spring.application.name=${artifactId}

# SpringDoc OpenAPI
springdoc.swagger-ui.doc-expansion=none
springdoc.swagger-ui.operations-sorter=alpha
springdoc.swagger-ui.tags-sorter=alpha

If PostgreSQL is selected:

properties

# PostgreSQL / JPA
spring.datasource.driver-class-name=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/${POSTGRES_DB:postgres}
spring.datasource.username=${POSTGRES_USER:postgres}
spring.datasource.password=${POSTGRES_PASSWORD:changeme}
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true

If Redis is selected:

properties

# Redis
spring.data.redis.host=localhost
spring.data.redis.port=6379
spring.data.redis.password=${REDIS_PASSWORD:changeme}

If MongoDB is selected:

properties

# MongoDB
spring.data.mongodb.host=localhost
spring.data.mongodb.port=27017
spring.data.mongodb.authentication-database=admin
spring.data.mongodb.username=${MONGO_USER:root}
spring.data.mongodb.password=${MONGO_PASSWORD:changeme}
spring.data.mongodb.database=${MONGO_DB:test}

6. Set Up Docker Compose

Create

docker-compose.yaml

at the project root with only the services the user selected.

yaml

services:
  # Include if PostgreSQL selected
  postgresql:
    image: postgres:17
    ports:
      - "5432:5432"
    environment:
      POSTGRES_USER: ${POSTGRES_USER:-postgres}
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-changeme}
      POSTGRES_DB: ${POSTGRES_DB:-postgres}
    volumes:
      - ./postgres_data:/var/lib/postgresql/data

  # Include if Redis selected
  redis:
    image: redis:7
    ports:
      - "6379:6379"
    command: redis-server --requirepass ${REDIS_PASSWORD:-changeme}
    volumes:
      - ./redis_data:/data

  # Include if MongoDB selected
  mongodb:
    image: mongo:8
    ports:
      - "27017:27017"
    environment:
      MONGO_INITDB_ROOT_USERNAME: ${MONGO_USER:-root}
      MONGO_INITDB_ROOT_PASSWORD: ${MONGO_PASSWORD:-changeme}
    volumes:
      - ./mongo_data:/data/db

7. Create

.env

File for Docker Compose

Create a

.env

file at the project root with default credentials for local development:

env

# PostgreSQL
POSTGRES_USER=postgres
POSTGRES_PASSWORD=changeme
POSTGRES_DB=postgres

# Redis
REDIS_PASSWORD=changeme

# MongoDB
MONGO_USER=root
MONGO_PASSWORD=changeme
MONGO_DB=test

Include only the variables for the services the user selected. Docker Compose automatically loads this file.

8. Update .gitignore

Append Docker Compose volume directories and the

.env

file to

.gitignore

# Docker Compose
.env
postgres_data/
redis_data/
mongo_data/

9. Verify the Build

Run the Maven build to confirm the project compiles and tests pass:

bash

./mvnw clean verify

If the build succeeds, inform the user. If it fails, diagnose and fix the issue before proceeding.

10. Present Summary to User

Display a summary of the created project:

Project Created Successfully

  Artifact:      <artifactId>
  Spring Boot:   <version>
  Java:          <javaVersion>
  Architecture:  <DDD | Layered>
  Build Tool:    Maven
  Docker:        <services list>

  Directory:     ./<artifactId>/

  Next Steps:
    1. cd <artifactId>
    2. docker compose up -d
    3. ./mvnw spring-boot:run
    4. Open http://localhost:8080/swagger-ui.html

Architecture Patterns

Layered Architecture

Traditional three-tier architecture with clear separation of concerns:

Layer	Package	Responsibility
Presentation	`controller/`	HTTP endpoints, request/response mapping
Business	`service/`	Business logic, transaction management
Data Access	`repository/`	Database operations via Spring Data
Domain	`model/`	JPA entities and DTOs

Best for: Simple CRUD applications, small-to-medium services, teams new to Spring Boot.

DDD Architecture

Domain-Driven Design with hexagonal boundaries:

Layer	Package	Responsibility
Domain	`domain/`	Entities, value objects, domain services (framework-free)
Application	`application/`	Use cases, orchestration, DTO mapping
Infrastructure	`infrastructure/`	JPA adapters, external integrations, configuration
Presentation	`presentation/`	REST controllers, error handling

Best for: Complex business domains, microservices with rich logic, long-lived projects.

Examples

Example 1: Simple REST API with PostgreSQL (Layered)

User request: "Create a Spring Boot project for a REST API with PostgreSQL"

bash

curl -s https://start.spring.io/starter.zip \
  -d type=maven-project \
  -d bootVersion=3.4.5 \
  -d groupId=com.example \
  -d artifactId=my-api \
  -d packageName=com.example.myapi \
  -d javaVersion=21 \
  -d dependencies=web,data-jpa,postgresql,validation,testcontainers \
  -o starter.zip

Result: Layered project with

controller/

service/

repository/

model/

packages, PostgreSQL Docker Compose, and SpringDoc OpenAPI.

Example 2: Microservice with DDD and Multiple Stores

User request: "Bootstrap a Spring Boot 3 microservice with DDD, PostgreSQL and Redis"

bash

curl -s https://start.spring.io/starter.zip \
  -d type=maven-project \
  -d bootVersion=3.4.5 \
  -d groupId=com.acme \
  -d artifactId=order-service \
  -d packageName=com.acme.order \
  -d javaVersion=21 \
  -d dependencies=web,data-jpa,postgresql,data-redis,validation,testcontainers \
  -o starter.zip

Result: DDD project with

domain/

application/

infrastructure/

presentation/

packages, PostgreSQL + Redis Docker Compose, and SpringDoc OpenAPI.

Best Practices

Always use Spring Initializr for project generation to get the correct dependency management and parent POM.
Use Java records for DTOs — they are immutable and concise.
Keep domain layer framework-free in DDD architecture — no Spring annotations in
```
domain/
```
.
Use environment variables for sensitive configuration in production (database passwords, etc.).
Pin Docker image versions in
```
docker-compose.yaml
```
to avoid unexpected breaking changes.
Run
./mvnw clean verify
after setup to ensure everything compiles and tests pass.
Add Testcontainers for integration tests instead of relying on Docker Compose.

Constraints and Warnings

Spring Initializr requires internet access — this skill cannot work offline.
Spring Boot 4.x availability depends on the current release cycle — check start.spring.io for latest versions.
Docker Compose credentials are loaded from
```
.env
```
file (git-ignored) — never commit secrets to version control.
The
```
spring.jpa.hibernate.ddl-auto=update
```
setting is for development only — use Flyway or Liquibase in production.
ArchUnit version must be compatible with the JUnit 5 version bundled with Spring Boot.

spring-boot-project-creator

NPX Install

Tags

SKILL.md Content

Spring Boot Project Creator

Overview

When to Use

Prerequisites

Instructions

1. Gather Project Configuration

2. Generate Project with Spring Initializr

3. Add Additional Dependencies

4. Create Architecture Structure

Option A: Layered Architecture

Option B: DDD (Domain-Driven Design) Architecture

5. Configure Application Properties

6. Set Up Docker Compose

7. Create
`.env`
File for Docker Compose

8. Update .gitignore

9. Verify the Build

10. Present Summary to User

Architecture Patterns

Layered Architecture

DDD Architecture

Examples

Example 1: Simple REST API with PostgreSQL (Layered)

Example 2: Microservice with DDD and Multiple Stores

Best Practices

Constraints and Warnings