Just because you rewrite some of the slow bits in C, doesn't mean you get don't get a big win using python. I would bet the parts in C don't need to be as agile

Just because you rewrite some of the slow bits in C, doesn't mean you get don't get a big win using python. I would bet the parts in C don't need to be as agile as all the other parts; the GUI, rest client etc. So you can iterate fast, and drop to C when you need to.