Abstract: Systems and methods are described for a wireless asset-tracking system that enables automated continuous characterization of aspects of shipment flow through a supply chain. In various embodiments, modular wireless tracking devices traveling with shipments report location and other data to a computational back end. The data are processed by analytic software running on the back end, which produces outputs such as supply-chain maps and metrics. The back-end software monitors for anomalies (e.g., delays, diversions) and notifies the user of prominent issues. In addition, the software remotely manages power consumption by trackers. It may also indicate opportunities for improving the efficiency of the supply chain.