First round:

Very easy 4 or 5 HackerRank tasks. If you invest a little time going through HackerRank exercises, it won't be a problem.

Second round:

Talk with 3 devs from TransferWise. It was not hard; they were just interested in what you learned so far. We talked about key concepts. They also prepared a little HackerRank exercise related to promises.

What bothered me is that one of the interviewers disconnected for 5 minutes just after asking a question. Later, the feedback contained the question flagged, stating that I didn't answer the question correctly (I did).

Third round:

Product interview. And here I failed. You have to be really, really, really careful what you answer to their questions. If you can't come up with a good example for their question, they just flag it and include it in the improvement section.

So if it takes time to come up with examples for:

• What you had to solve for a user?
• How you shaped the requirements for the user?
• What app you like and know they are missing a feature?
• What that feature is?
• How would you start designing and implementing it?
• How would you measure its success?
• What data would you check if you were the CEO?

then practice it until it is second nature to you, otherwise they will just reject you.

(Also try to get information about how their teams work and how they ship a feature end-to-end, because if you don't know, if you don't describe the same process, then they will include it in the improvement section too.)