Easy, as usual, but could be more efficient. If you're an experienced developer, it should be easy to pass. So, basically, you can try this before others. Some of the interviewers are not professional.
What's the biggest challenge of your project?
The following metrics were computed from 9 interview experiences for the Rakuten Applications Engineer role in Japan.
Rakuten's interview process for their Applications Engineer roles in Japan is fairly selective, failing a large portion of engineers who go through it.
Candidates reported having very good feelings for Rakuten's Applications Engineer interview process in Japan.