Matlab Neural Network Toolbox vs. Wolfram Neural Network Framework

Does anyone who has worked with both Matlab and Mathematica compare to how the Matlab Neural Network Toolbox is compared to Mathematica?

As far as I know, Mathematica is a nice interface for MXNet and has a Wolfram language encoder and decoder that automates the data preparation for the network capture and back. So is Matlab doing something different, using his Neural Network in his own language, and not using an open source implementation? If the answer is no, which open source implementation is used?