Duolingo Software Engineer interview experience

After the first round of selection, I received clear instructions and then got emails if I passed, including a short window of about five days to get into the next phase. Across the journey, it felt somewhat long and tedious, but also pretty standard: I worked through HackerRank, then had an HR call, and later a one-hour technical video chat. The final day turned into multiple technical interviews, including one that involved looking at their codebase and two more conventional coding rounds.