I propose to accept NEP-22, "Duck typing for NumPy arrays – high level overview": http://www.numpy.org/neps/nep-0022-ndarray-duck-typing-overview.html This NEP didn't generate much (any?) discussion on the mailing list when Nathaniel and I sent it out a few months ago. But I still think the high-level vision makes sense, and it would be nice to mark this informational NEP as accepted to lay-out a clear vision for how we want to handle "duck arrays". One nice thing about informational NEPs is that they don't commit us to any particular choices, so marking the NEP as is accepted is relatively low risk :). There are still plenty of details to refine (as we did in NEP-18), but we can take our time on that. Cheers, Stephan