Rößling et al., in [2], provide an overview of current CS specific on-line learning resources and guidance on how one might better about extending an LMS to include such tools and resources. They focus specifically on full-featured, extensible LMSs similar to Blackboard and Moodle. They do not prescribe how to write a plug-in for existing LMSs, nor to promote one LMS over another, but rather to describe the features and characteristics proposed plug-ins and extensions should have.