Jeka

JEKA is a Java build tool ala Ant, Maven or Gradle but relying only on Java code to express builds instead of XML or external DSL.

Jeka aims at making build process more straightforward for Java developers, even for complex cases. 

Existing solutions are judged unsatisfactory by many users : either they found it too verbose, too rigid or requiring too much extra cognitive load. 

Jeka let Java developers build projects and automate tasks using the good old technology they are comfortable with : Java code, native IDE support and regular libraries. With Jeka, users can write, design, reuse, refactor, debug "build code" as they would do with regular production code.

Also, Jeka adopts "Easiest for easy things" principle. If your project structure is not too specific, then you only need a really minimalist setup (without code) to build it.