[dimatura]

Seems like out of the major libraries (TF/Caffe/Theano/pytorch), pytorch is the only one to have a core that is C (the TH*). It's not exactly a small library, though. One small library that is in C and has some state-of-the-art features is Darknet (https://pjreddie.com/darknet).

That said, seems like directly using the C++ API was a major use case here, and it looks fairly clean to me.

[kgwgk]

Does the C (or is it C++?) core of pytorch come directly from torch or do they add more functionality? Is there a way to interface with this core using C?

[albertzeyer]

TensorFlow and Caffe are also implemented in C++.

[kgwgk]

Being implemented in C++ doesn't ensure that a C++ interface exists. A C++ API is available for TensorFlow, though, and also a C API.