An electromechanical actuator package for actuating a brake assembly configured to operate a vehicle brake comprises: a motor; a differential operably connected to the motor, the differential comprising a pulley and an output connectable to the brake assembly; and a locking mechanism configured to lock the pulley of the differential, the locking mechanism comprising: a base configured to be movable, a plurality of projections projecting from the movable base, the projections comprising first and second projections, wherein at least a part of the pulley is positioned between the first and second projections projected from the movable base, an electromagnet assembly disposed adjacent to at least one of the projections, the electromagnet assembly operably associated with at least one of the projections, and one or more springs operably coupled to the movable base and/or at least one of the projections.