I don't see any claims about performance, but I would be very surprised if it was anything better than abysmal. In a modern neural network pipeline, just sending data to the CPU memory is treated as a ridiculously expensive operation, let alone serializing to a delimited text string.

Come to think of it, this is also a problem with the Unix philosophy in general, in that it requires trading off performance (user productivity) for flexibility (developer productivity), and that trade-off isn't always worth it. I would love to see a low overhead version of this that can keep data as packed arrays on a GPU during intermediate steps, but I'm not sure it's possible with Unix interfaces available today.

Maybe there's a use case with very small networks and CPU evaluation, but so much of the power of modern neural networks comes from scale and performance that I'm skeptical it is very large.