Karura is using SubQuery to extract and query data from Karura’s chain, making queries fast and efficient for Karura’s app.

“Using Subquery makes building dapps easy, no more making a complicated series of calls to get the data I need.” — Brett (Developer at Acala)

https://subquery.medium.com/karura-integrates-with-subquery-to-aggregate-and-serve-defi-data-to-kusama-builders-d34f0e722311