Commercially available peristaltic pumps for microfluidics are usually bulky, expensive, and not customizable. Herein, we developed a cost-effective kit to build a micro-peristaltic pump (~ 50 USD) consisting of 3D-printed and off-the-shelf components. We demonstrated fabricating two variants of pumps with different sizes and operating flowrates using the developed kit. The assembled pumps offered a flowrate of 0.02 ~ 727.3 μL/min, and the smallest pump assembled with this kit was 20 × 50 × 28 mm. This kit was designed with modular components (i.e., each component followed a standardized unit) to achieve (1) customizability (users can easily reconfigure various components to comply with their experiments), (2) forward compatibility (new parts with the standardized unit can be designed and easily interfaced to the current kit), and (3) easy replacement of the parts experiencing wear and tear. To demonstrate the forward compatibility, we developed a flowrate calibration tool that was readily interfaced with the developed pump system. The pumps exhibited good repeatability in flowrates and functioned inside a cell incubator (at 37 °C and 95 % humidity) for seven days without noticeable issues in the performance. This cost-effective, highly customizable pump kit should find use in lab-on-a-chip, organs-on-a-chip, and point-of-care microfluidic applications.