Following recent experimental updates on hyperon decay parameters, hyperon nonleptonic transitions are studied in relativistic chiral perturbation theory ($\chi$PT). Previous computations of the next-to-leading-order (NLO) corrections to the decay amplitude were carried out in non-relativistic frameworks. We attempt a (re)calculation of one-loop corrections in relativistic $\chi$PT in the EOMS renormalization scheme. We present our results for the combined fit to S- and P-wave amplitudes, as well as the relative importance of the considered contributions, such as the role of resonances and decuplet baryons as intermediate states. Our goal is to provide an updated theoretical description of weak nonleptonic hyperon decays in $\chi$PT up to one-loop corrections, based on the most recent data and theoretical framework.