This paper outlines a system description and small-scale usability study of An Bat Mírialta - ('The Irregular Verb Bot'), a newly developed educational application embedded within the Irish intelligent-Computer Assisted Language Learning (iCALL) platform, An Scéalaí (www.abair.ie/scealai). An Bat Mírialta is being developed to aid learners in their mastery of the 11 irregular verbs of Irish. The work is presented in the context of a novel conceptual framework for CALL artefact design, implementation and evaluation - LeTAT. Challenges and concerns faced in developing an educational technology for a low-resource, endangered language are also described.