why there is no Spark MLlib ?

[vadymhimself]

No description provided.

[grahamjenson]

There are a lot of general purpose machine learning tools that can be used to build a recommender systems. We could add a category specifically for those targeted at the domain. However, at the moment this list is trying to focus on systems that are recommender systems "out of the box".

If you would like to submit a PR with a new category for "Tools used to build recommender systems" I would merge that.