* Creates upgrade options with only the --model-version option set.
     *
     * @param modelVersion the --model-version option value
     * @return configured upgrade options
     */
    public static UpgradeOptions createOptionsWithModelVersion(String modelVersion) {
        return createOptions(null, null, null, null, modelVersion);
    }

    /**
     * Creates upgrade options with only the --plugins option set.
     *

    private final List<Property> properties = new ArrayList<>();

    public static PomBuilder create() {
        return new PomBuilder();
    }

    public PomBuilder modelVersion(String modelVersion) {
        this.modelVersion = modelVersion;
        return this;
    }

    public PomBuilder namespace(String namespace) {
        this.namespace = namespace;
        return this;
    }

            String pomXml = """
                <?xml version="1.0" encoding="UTF-8"?>
                <project xmlns="http://maven.apache.org/POM/4.0.0">
                    <modelVersion>4.0.0</modelVersion>
                    <dependencies>
                        <dependency>
                            <groupId>test</groupId>
                            <artifactId>test</artifactId>

 utilized across all your Maven projects.

+-----+
 m0 <- m1 <- m2
+-----+

 which is transformed into

+-----+
 super model <- m0 <- m1 <- m2
+-----+

+-----+
<project>
 <modelVersion>4.0.0</modelVersion>
 <parent>
   <groupId></groupId>
   <artifactId></artifactId>
   <version></version>
 </parent>
</project>
+-----+

Extending the POM in the future

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t04-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t06-d</artifactId>
  <packaging>jar</packaging>
  <version>1.2</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t10-c</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>

        model = builder.build();
        String modelVersion = new MavenModelVersion().getModelVersion(model);
        if (!ModelBuilder.MODEL_VERSION_4_0_0.equals(modelVersion) && !preserveModelVersion) {
            warnNotDowngraded(project);
        }
        model = model.withModelVersion(modelVersion);

        return model;
    }

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t09-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>

  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t09-c</artifactId>
      <version>1.0</version>
      <scope>compile</scope>
    </dependency>
  </dependencies>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t05-c</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t05-d</artifactId>
      <version>1.1</version>
      <type>jar</type>
      <scope>compile</scope>
      <optional>true</optional>
    </dependency>
  </dependencies>