I use the same combo: lots of Python to analyse problems, test algos, process data, etc. Then, once I settle on a solution but still need more performance (outside GPU's), I go to rust.
I'm simulating an audio speaker in real time. So I do the data crunching, model fitting, etc. in python and this gives me a godd theoretical model of the speaker. But to be able to make a simulation in realtime, I need lots of speed so rust makes sense there (moreover, the code I have to plug that in is rust too, so one more reason :-)). (now tbh, my realtime needs are not super hard, so I can avoid a DSP and a real time OS :-) )
I don't need rust specifically. It's just that its memory and thread management really help me to continue what I do in python: focusing on my core business instead of technical stuff.
