The following steps:

1. HR Call (ca 30min).
2. Technical Call to discuss your prior experience and general technical questions (ca 45min).
3. Technical Call with coding: a brief discussion of your prior experience, then a medium LC problem in CoderPad (ca 45min, but I had around 60 min because the discussion of my experience took a little longer; total for the coding problem I'd say around 25 min in total).
4. Probably some other round or rounds, I have no clue, thanks to the HR.

Issues/downsides:

1. My HR had no previous technical hiring background, so he couldn't answer my questions and couldn't provide a clear roadmap of what to expect from interviews and how many rounds there are. He also "recommended" not to ask compensation questions during the next stages (thanks for the "valuable" tip) in a very rude manner, when I asked him such a question (which is logical from my side, because he asked me about my expectations). HR basically has no clue about the position and about the tasks one should do in the position.
2. The booking system is like from the 2000s: you get an email asking your availability, you should respond to it via email, then you get the invitation, and here you also should respond with an acknowledgement confirming the proposed appointment.
3. The LeetCode problem description is EXTREMELY shady and unclear; they basically took a problem from LC and swapped several paragraphs with the description with the word "alternatively", providing only one example, so one has to waste extra minutes to understand the assignment.
4. After more than 5 weeks have passed since the last interview round, and during the wait, I have not received a single message (I inquired several times about the processing times and the feedback, though I got a response once asking to wait extra weeks).

At the end, the template rejection came on a Sunday from a generic e-mail address with no feedback.

Overall, an abysmal experience, I couldn't recommend this company.

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What if there is a conflict on a technical matter? How would you address it?

LeetCode problem 2149 (Rearrange Array Elements by Sign)