A pumping system pumps material or fluid downhole, for example, to perform a stimulation operation. The pumping system can include a hydraulic pump coupled to an intensifier. The intensifier may have a piston which allows for a small footprint as compared to an intensifier with a plunger. The hydraulic cylinder of the intensifier may be protected from the corrosive, erosive and/or abrasive effects of the material or fluid to be pumped by one or more seals. Using the intensifier that includes a piston may provide for a greater reliability of the overall pumping system, as fewer strokes are required, and a compact pumping system, as the stroke length of the intensifier with a piston is less than the stroke length required for a plunger.