*
     * @param project {@link Project} or {@code null}.
     * @return the effective properties, never {@code null}
     */
    @Nonnull
    Map<String, String> getEffectiveProperties(@Nullable Project project);

    /**
     * Returns the current maven version
     * @return the maven version, never {@code null}
     */
    @Nonnull
    Version getMavenVersion();

    int getDegreeOfConcurrency();