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

    int getDegreeOfConcurrency();

    @Nonnull
    Instant getStartTime();

    /**
     * Gets the directory of the topmost project being built, usually the current directory or the
     * directory pointed at by the {@code -f/--file} command line argument.
     */
    @Nonnull