brain – Javascript for supervised machine learning
From the website:
brain is a JavaScript library for neural networks and Bayesian classifiers.
The documentation reports that by default it stores in memory but it also has a Redis backend.
Reported to be used for spam filtering. Filtering is predicated on recognition of some basis for filtering, dare I say subject recognition? There are some subjects that are classes, such as spam, which are composed of included subjects, such as individual spam senders or messages. How fine grained subject recognition need be really depends upon the purpose of recognition.
What subjects are you filtering for?