JHipster supports using either Maven or Gradle as the build tool for the server-side code. Both are free and open source.

Maven (https://maven.apache.org) is a build automation tool that uses an XML document called pom.xml to specify how an application is built and its dependencies. Plugins and dependencies are downloaded from a central server and cached locally. The Maven build file is called a Project Object Model (POM) and it describes the build process. Maven has a long history and is much more stable and reliable than Gradle. It also has a huge ecosystem of plugins. JHipster provides its own BOM (short for Bill Of Materials; https://github.com/jhipster/jhipster) to make dependency management easier.

Gradle (https://gradle.org) is a build automation tool that uses a Groovy DSL to specify the build plan and dependencies. Gradle is much more flexible and feature-rich than Maven, making it an ideal choice for very complex build setups. The latest version of Gradle easily surpasses Maven in terms of speed and features. Another unique advantage of Gradle is the ability to write standard Groovy code in the build script, making it possible to do pretty much everything programmatically. It has great plugin support as well. Gradle also provides a Kotlin DSL (https://gradle.org/kotlin/).