Theme 1 – Definitionand scope of autodiff
"Automatic differentiation. For any DAG with a scalar output, it allows calculating its partial derivative wrt the input parameters." — niv
Theme 2 – Need for clearer introductory material
"I liked this one, but it took me a while to understand, I think this page is a much better intro:" — sowow
Theme 3 – Importance of robust error handling
"Clean implementation. One thing I always look for: how does this degrade when things go wrong? Good error handling is what separates weekend projects from tools people actually use." — hbwang2076