They also use Yandex. https://kagifeedback.org/d/5445-reconsider-yandex-integratio... , which is why I cancelled.

They have since removed all mentions of it and other names of the indexes that they use from their docs.

Basically you have no transparency and no clue how much of your money is going where. Could be that 80% of your results are Google index, 10% Bing, 5% Yandex and 5% independent indexes and you have no way of knowing.

That's why I switched to Uruky, where I have actual control over where my money goes. I mainly use EUSP, Mojeek, Linkup, Marginalia and if I can't find what i'm looking for only then go to a fallback search engine (that you can set inside) like DDG, Brave, Ecosia. There's a couple of other smaller open source indexes that they use (including their own).