Create Spring Boot Kotlin project prompt Please make sure you have the following software installed on your system: Java 21 Docker Docker Compose If you need to custom the project name, please change the artifactId and the packageName in download-spring-boot-project-template If you need to update the Spring Boot version, please change the bootVersion in download-spring-boot-project-template Check Java version Run following command in terminal and check the version of Java java -version Download Spring Boot project template Run following command in terminal to download a Spring Boot project template curl https://start.spring.io/starter.zip \ -d artifactId = ${input : projectName : demo-kotlin} \ -d bootVersion = 3.4 .5 \ -d dependencies = configuration-processor,webflux,data-r2dbc,postgresql,data-redis-reactive,data-mongodb-reactive,validation,cache,testcontainers \ -d javaVersion = 21 \ -d language = kotlin \ -d packageName = com.example \ -d packaging = jar \ -d type = gradle-project-kotlin \ -o starter.zip Unzip the downloaded file Run following command in terminal to unzip the downloaded file unzip starter.zip -d ./ ${input : projectName : demo-kotlin} Remove the downloaded zip file Run following command in terminal to delete the downloaded zip file rm -f starter.zip Unzip the downloaded file Run following command in terminal to unzip the downloaded file unzip starter.zip -d ./ ${input : projectName : demo-kotlin} Add additional dependencies Insert springdoc-openapi-starter-webmvc-ui and archunit-junit5 dependency into build.gradle.kts file dependencies { implementation("org.springdoc:springdoc-openapi-starter-webflux-ui:2.8.6") testImplementation("com.tngtech.archunit:archunit-junit5:1.2.1") } Insert SpringDoc configurations into application.properties file

SpringDoc configurations

springdoc.swagger-ui.doc-expansion

none springdoc.swagger-ui.operations-sorter = alpha springdoc.swagger-ui.tags-sorter = alpha Insert Redis configurations into application.properties file

Redis configurations

spring.data.redis.host

localhost spring.data.redis.port = 6379 spring.data.redis.password = rootroot Insert R2DBC configurations into application.properties file

R2DBC configurations

spring.r2dbc.url

r2dbc:postgresql://localhost:5432/postgres spring.r2dbc.username = postgres spring.r2dbc.password = rootroot spring.sql.init.mode = always spring.sql.init.platform = postgres spring.sql.init.continue-on-error = true Insert MongoDB configurations into application.properties file

MongoDB configurations

spring.data.mongodb.host

localhost spring.data.mongodb.port = 27017 spring.data.mongodb.authentication-database = admin spring.data.mongodb.username = root spring.data.mongodb.password = rootroot spring.data.mongodb.database = test Create docker-compose.yaml at project root and add following services: redis:6 , postgresql:17 and mongo:8 . redis service should have password rootroot mapping port 6379 to 6379 mounting volume ./redis_data to /data postgresql service should have password rootroot mapping port 5432 to 5432 mounting volume ./postgres_data to /var/lib/postgresql/data mongo service should have initdb root username root initdb root password rootroot mapping port 27017 to 27017 mounting volume ./mongo_data to /data/db Insert redis_data , postgres_data and mongo_data directories in .gitignore file Run gradle clean test command to check if the project is working ./gradlew clean test (Optional) docker-compose up -d to start the services, ./gradlew spring-boot:run to run the Spring Boot project, docker-compose rm -sf to stop the services. Let's do this step by step.