For ML (reverse-mode autodiff): * <https://github.com/can-lehmann/exprgrad> can differentiate any expression * <https://github.com/mratsim/arraymancer> can differentiate preconfigured layers
And actually autodiff was my very first foray into Nim: <https://github.com/mratsim/nim-rmad> (This uses similar approach to Spacy: <https://github.com/explosion/thinc>, <https://github.com/explosion/thinc/blob/master/thinc/layers/add.py#L42-L48> ) The author of <https://github.com/autodiff/autodiff> wanted to do an autodiff in Nim 4 years ago: <https://forum.nim-lang.org/t/5157#32348>
