While recommender-system software libraries and APIs support you in developing a recommender system, a Recommender-System As-a-Service (RaaS) does all the work for you. Typically, you can integrate a recommender system into e.g. your e-commerce website or blog with a few clicks or lines of code. A RaaS comes with some compromises relating to flexibility, control and effectiveness when compared to a custom-made recommender system. However, a RaaS typically is highly scalable and delivers reasonable results after a few hours or even minutes — compared to months of development for a custom-made recommender system.
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