Walmart has an awesome research and development labs known as Walmart Labs in Bangalore. Flipkart has its development headquarters in Bangalore too. They have awesome engineers too.
Both Walmart Labs and Flipkart hire the best computer scientists and software engineering talent from across the country. They pay as much as and sometimes more than what Google Bangalore pays its engineers.
With Walmart now acquiring a majority stake in Flipkart, I can see the two strong and highly skilled engineering centers coming together and forming a formidable team to give a tough competition to Amazon.