Rigi is an interactive, visual tool designed to help developers and organizations better understand and re-document their software. It has been in development over the past decade. Two main goals for the Rigi project are to provide an infrastructure for research and practice in program understanding, and to discover abstractions in large software systems, and to pass this information on to software engineers for maintenance and reengineering purposes. The general Rigi graph model, and the supporting graph editor (rigiedit) arose as result of our early work on algorithms for the analysis, representation, and visualization of software structure.

Currently the Rigi group is focusing on visualization support to aid in the understanding and reverse engineering of legacy systems.