Abstract: A modular skid for supporting a machinery assembly. The modular skid includes a skid base with opposing side rails and a support deck extending there between. The modular skid further includes a skid extension and an end cap. The skid extension including an extension support deck having a width corresponding to the width of the skid base. One end of the skid extension is configured to mount to the mounting features of the skid base. At an opposing end of the skid extension, the extension side rails defining extension mounting features of the skid extension. The extension mounting features have a configuration that corresponds to the base mounting features. The end cap includes end cap mounting structures configured to be alternately mounted to the base mounting features or the extension mounting features.