@Input
    public ListProperty<String> getIncludeXpack() {
        return includeXpack;
    }

    public void setSubstitutions(Map<String, String> substitutions) {
        this.substitutions = substitutions;
    }

    @Input
    @Optional
    public Map<String, String> getSubstitutions() {
        return substitutions;
    }

    @SkipWhenEmpty
    @InputFiles
    public FileTree getInputDir() {