It's a fast moving field. In the past 5 years we've scene enthusiasm for Caffe, luatorch, theano, tensorflow, and most recently pytorch. And tensorflow 2 of course, which totally changes the programming model. Our own library changes to keep up to date with the field.
Having said that, v1 isn't changing much now - v2 (out soon) will be where new ideas go, and only bug fixes will go to v1, so you can stick with that as long as you like.
Obviously it is moving fast at the bleeding edge. But the basics of backprop have not changed for a while, and somehow I would think that a toolchain that I would expect to be a serious tool for practical purposes and not just a display of the bleeding edge would at least be backwards compatible with previous versions.
(I hope I am not writing this in too harsh way. I actually liked your videos so much that I am seriously considering applying for your on site course if I one day just get all the other issues sorted out in my life so that I can relocate to SF for a couple of months)
Having said that, v1 isn't changing much now - v2 (out soon) will be where new ideas go, and only bug fixes will go to v1, so you can stick with that as long as you like.