plot_icc() can both produce a basic conditional Item Characteristic Curves plot and optionally a DIF ICC plot, the latter also reporting a partial gamma DIF magnitude coefficient. This is inspired by iarm::ICCplot()
person_parameters() to retrieve person locations (latent scores) using EAP and WLE, and also a transformation table from ordinal sum score to EAP/WLE.
posterior_to_prior() that extracts priors from a brmsfit model that may be useful in model fit assessment. An article will be added later, exploring this further.