  We calculate the Big Bang Nucleosynthesis abundances for helium-4 and
deuterium for a range of neutron lifetimes, $\tau_n = 840 - 1050$ s, using the
state-of-the-art Python package \textsc{PRyMordial}. We show the results for
two different nuclear reaction rates, calculated by NACRE II [1] and the PRIMAT
[2] collaborations.
