Introduction

The Stanford Exploration Project (SEP) has been at the forefront of computational reproducible research for many years. Beginning with the introduction of active (a-doc) and interactive (i-doc) documents by Claerbout (1990), SEP progressed to reproducible scripting using cake Nichols and Cole (1989) and archiving on CD-ROMS to ensure that entire reports, along with original codes and processing flows, could be distributed easily and cheaply. An additional change occurred around SEP-89 when the more flexible GNU Make software was introduced at SEP Schwab and Schroeder (1995). Testing of the reproducible workflows to ensure complete repeatability became common practice by SEP-77 Prucha et al. (1999).

In the summer 2006, SEP began transitioning from the Make system to SCons (Softwar Constrution), an open-source software construction based on the Python scripting language. The transition was largely inspired by the work of Fomel and Hennenfent (2007), who released the RSF/Madagascar package for generating geophysical (and more general processing) work flows. A main goal of this project was harnessing the scripting power of Python into a package for generating and checking the processing flow rules. Using the RSF/Madagascar as a model, SEP adapted and reengineered certain aspects of the package that were not completely tooled for SEP's research, development and computer environment. One of the main goals was to facilitate an easy transition to SCons for all SEP personnel by retaining a lot of the Make functionality. However, due to the use of a different scripting language and reproducibility philosophy, we have included a number of new features reported herein.