Does anyone know of an open source recommendation engine? I would love to just explore how one works bet it seems like this solely in the realm of proprietary

Does anyone know of an open source recommendation engine? I would love to just explore how one works bet it seems like this solely in the realm of proprietary software at the moment. I have a dream of naively making a open source recommendation engine using data from good reads and imdb. There is a real utility here that I worry will be captured entirely by companies without an open source alternative.