The pair distribution function (PDF) reveals directly in real space the interatomic distances in a material. Recent applications have proved the PDF technique to be a powerful local-structure probe of nanostructured materials (Egami & Billinge, 2003; Billinge & Kanatzidis, 2004), in addition to its traditional use to study liquids and glasses (Furukawa, 1962; Wright, 1998). The experimental PDF is obtained by a sine Fourier transformation of the total-scattering structure function S (Q), where Q is the magnitude of the scattering vector. To obtain S (Q) from raw scattering intensities, many corrections have to be made to account for various instrument and sample effects. Adding to this complexity, most existing X-ray data PDF analysis software is menu driven and not particularly user-friendly. Reproducing an earlier data analysis has been difficult because data processing parameters are usually kept in the notebook other than with the data. Cross-platform compatibility has also been an issue.