Very similar in spirit, but still different in the details. Dual numbers use nilpotent infinitesimals (which are not invertible), while non-standard (Robinson)

Very similar in spirit, but still different in the details. Dual numbers use nilpotent infinitesimals (which are not invertible), while non-standard (Robinson) infinitesimals are not nilpotent and are invertible. That being said it's way easier to construct nilpotent infinitesimals using intuitionistic logic than it is to construct the hyperreals using classical logic.