SWE applicants have rated the interview process at Duolingo with 3.5 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 50% positive. To compare, the company-average is 47.5% positive. This is according to Glassdoor user ratings.
Here are the most commonly searched roles for interview reports -
First you are given an online assessment (which is on the harder side) and then you do a Karat interview. I believe there is one more round after that, but I didn't make it there.
Interview questions [1]
Question 1
Show you functions / variations of functions that do the same thing and you have to analyze runtime/space
I didn't pass the hackerrank, but I believe there's a few more technical rounds after that. The response after the hackerrank was prompt, and the initial recruiter contact point was prompt too after submitting an application