this.userProperties = userProperties;
            return this;
        }

        public ModelBuilderRequestBuilder repositoryMerging(RepositoryMerging repositoryMerging) {
            this.repositoryMerging = repositoryMerging;
            return this;
        }

        public ModelBuilderRequestBuilder repositories(List<RemoteRepository> repositories) {

    @Override
    public DefaultProjectBuildingRequest setRepositoryMerging(RepositoryMerging repositoryMerging) {
        this.repositoryMerging = Objects.requireNonNull(repositoryMerging, "repositoryMerging cannot be null");
        return this;
    }

    @Override
    public RepositoryMerging getRepositoryMerging() {
        return repositoryMerging;
    }

    private final ProjectBuildingRequest.RepositoryMerging repositoryMerging;

    public ProjectModelResolver(
            RepositorySystemSession session,
            RequestTrace trace,
            RepositorySystem resolver,
            RemoteRepositoryManager remoteRepositoryManager,
            List<RemoteRepository> repositories,
            ProjectBuildingRequest.RepositoryMerging repositoryMerging,
            ReactorModelPool modelPool) {

        List<ArtifactRepository> dominantRepositories;
        List<ArtifactRepository> recessiveRepositories;

        if (ProjectBuildingRequest.RepositoryMerging.REQUEST_DOMINANT.equals(request.getRepositoryMerging())) {
            dominantRepositories = externalRepositories;
            recessiveRepositories = internalRepositories;
        } else {

              <!-- was only a workaround for Plexus Container, hopefully never used by anyone else -->

                    configuration.setProcessPlugins(false);
                    configuration.setRepositoryMerging(ProjectBuildingRequest.RepositoryMerging.REQUEST_DOMINANT);
                    MavenSession session = legacySupport.getSession();
                    if (session != null) {
                        configuration.setSystemProperties(session.getSystemProperties());