recalot.com is a GPL-licensed Java REST web service for recommender systems (version 1.8). It can be used for scientific (like offline evaluation) as well as productive application.
The ideas behind recalot.com are to build a RESTFul recommender system that can be used for all sorts of applications, can easily be extended, can be used for offline as well as online evaluations and can be adjusted for scientific as well as industrial applications. Therefor, we decide to build the API with the help of Apache Felix, which is an OSGi Framework. This allows a modular development, modules can easily be replaced in runtime and modules with new functionality can easily be added to the system. Currently, the system is in an alpha phase, but you can try it out and give us feedback. The architecture of recalot.com is following the MVC pattern and distinguishes between data, recommendations and evaluation affiliation. (see Architecture).