In one aspect, a brake pump assembly including a plurality of pairs of pumping elements configured in a horizontally opposed arrangement, and a rotatable eccentric assembly located between the pumping elements. The pairs of pumping elements abut the eccentric assembly and are reciprocally driven to provide an output of pressurized fluid. In another aspect, a brake pump assembly including a hydraulic block defining a piston bore, and a pumping element received in that bore. The pumping element includes a polymer piston, and a circumference of the polymer piston defines a high-pressure seal slideably engaging adjacent structure. In another aspect, a hydraulic block coupled to an electronic control unit, the hydraulic block including a plurality of pairs of pumping elements located in a horizontally opposed arrangement, and an embedded pressure sensor, the pressure sensor being adjacent to but vertically separated from the pumping elements.