By default, the repackage goal will replace the original artifact with the repackaged one. That's a sane behavior for modules that represent an app but if your module is used as a dependency of another module, you need to provide a classifier for the repackaged one.

The reason for that is that application classes are packaged in BOOT-INF/classes so that the dependent module cannot load a repackaged jar's classes. If that is the case or if you prefer to keep the original artifact and attach the repackaged one with a different classifier, configure the plugin as follows:

<project>
  ...
  <build>
    ...
    <plugins>
      ...
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        <version>2.0.9.BUILD-SNAPSHOT</version>
        <executions>
          <execution>
            <goals>
              <goal>repackage</goal>
            </goals>
            <configuration>
              <classifier>exec</classifier>
            </configuration>
          </execution>
        </executions>
        ...
      </plugin>
      ...
    </plugins>
    ...
  </build>
  ...
</project>

This configuration will generate two artifacts: the original one and the repackaged counter part produced by the repackage goal. Both will be installed/deployed transparently.