C++ might be used. By calling it from Python or Java or Haskell, which will allow you to iterate 10 times faster than using it directly. Startups are trying to

C++ might be used. By calling it from Python or Java or Haskell, which will allow you to iterate 10 times faster than using it directly. Startups are trying to prove that their business idea works. This idea usually involves using existing technology to solve some business problems, rarely it requires development of lower layers of the stack. This may come later - or may come never. You can easily use machine learning without knowing what C++ is.