depending on individual preferences rankings such as "most bought items", "most viewed...", etc. Additionally, as an integration showcase, a MediaWiki extension was developed and is bundled with the application. Currently additional features like further recommender algorithms and a plugin-system are evaluated and prepared for integration into the easyrec system. Architecture The underlying architecture of easyrec is designed to be robust and scalable—separating time-consuming computations from the task of online assembling of recommendations. easyrec is designed as a multi-layer system consisting of a database layer as storage of user actions and pre-calculated business rules an application layer for hosting online and offline recommendation services and an API layer for various Web service interfaces. Moreover, the generator server contains different item association generators which create business rules that define a relation between two items. Footnotes Recommender systems Cross-platform software Cross-platform free software Free software programmed in Java (programming language) Free application software Free web software Software projects Web applications