I've been learning a lot about machine learning (mostly clustering and regressions), but when I've looked into programming libraries/environments, I've found "production ready" ones to be few and far between.
What I mean by "production ready" is that it could be incorperated into a product, not just used a tool to fool around with in order to find some relationships. For instants, Pandora is probably a good example of a company that uses some algorithm (I would guess logistical regression, but I don't really know) to compute values from code.
In Java, things like Weka and RapidMiner seem to include the ability to be called from code as an afterthought and it's always awkward to do. I can't imagine either of them being used in production. Python's too slow to use for anything very big (It's suppose to be "Big Data" after all) and R can't scale at all.
It's possible to write everything in pure Java/C++/C code, but why arn't there any good libraries targeted at programming designed for programming environments. I feel like I'm missing something. What are these big companies using?