Beyond the Standard Model processes at neutrino experiments have largely been unexplored due to the current effort required to implement these models into existing event generators. In this poster, I discuss the ongoing work within the Achilles event generator to automate this process. BSM effects are expected to first appear in the leptonic current. In Achilles, the cross section is factorized into the leptonic current and the hadronic current. This separation provides a means to leverage existing LHC tools for automated matrix element calculation for the leptonic current, while interfacing to advanced nuclear models. Validation of this method, along with results for heavy neutral leptons will be presented.