I am aware of the fact that there are many quantitative funds in India, at least some of which are prop shops. These include the India offices of foreign firms (eg: Tower Research, WorldQuant, Qube Research) but many seem to be Indian firms (eg: Graviton, AlphaGrep, Quadeye).
What is the quality of work at these places (both Indian offices of foreign firms and Indian firms)? What is the comp like, and how could one rank them? I believe many hire only from IITs or engineering schools of similar caliber.
On a related note, do BBs have any quant trading or more back-end quant work in India?