src/assembly/src-distribution.xml

<assembly xmlns="http://maven.apache.org/ASSEMBLY/2.1.1"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.1.1 https://maven.apache.org/xsd/assembly-2.1.1.xsd">
    <id>src</id>
    <formats>
        <format>tar.xz</format>
    </formats>
    <fileSets>
        <fileSet>
            <directory>${project.basedir}</directory>
            <includes>
                <include>*.md</include>
                <include>LICENSE*</include>
                <include>NOTICE*</include>
                <include>pom.xml</include>
                <include>config.groovy</include>
            </includes>
            <useDefaultExcludes>true</useDefaultExcludes>
        </fileSet>
        <fileSet>
            <directory>${project.basedir}/src</directory>
            <useDefaultExcludes>true</useDefaultExcludes>
        </fileSet>
    </fileSets>
</assembly>