Development economics is a plus of traditional economics and political economy. Does the development economists in the Sub-Sahara really set up research in the area, especially, the academics in Nigeria?
I do not know to Sub-Saharan countries but the Development Economics in its broad spectrum will be that which encompasses also ecological and equality problems.
I am not sure I understand the question. But, as a start, check the book entitled Economic Diversification and Growth in Africa: Critical Policy Making Issues and see if that is the kind of writing you mean. It is a small book, authored by Omotunde E. G. Johnson and published in 2016 by Palgrave Macmillan.