If you also attach it to an existing goal, say package, it's a little more convenient (no need to know about assembly:single). e.g.
```xml
                <executions>
                    <execution>
                        <id>assembly</id>
                        <phase>package</phase>
                        <goals>
                            <goal>assembly</goal>
                        </goals>
                    </execution>
                </executions>
```