Although Inside Stores uses a commercially-available shopping cart platform, it had many shortcomings for our use case. We solved this problem by creating an ancillary dashboard using ASP.NET and Silverlight.
Features for the supplemental dashboard included a variety of missing reports, data exports, real-time traffic monitors and database maintenance utilities; all intended to backfill holes in the commercial package.
The ASP.NET portion of this project also grew to include dozens of XML and REST Web API endpoints which could be called by the shopping cart to quickly access cached data and perfom complex queries which were well beyond the means of the original shopping cart software.
All architecture and programming. Written in Silverlight, ASP.NET, C#.