I interviewed as a Senior Software Engineer with 10 years of experience, 6 of which in a well-established software company.

The journey into Wise consists of 5 interviews:

• Intro interview: with a recruiter, talking about yourself and so on.
• Pair programming interview: a 45-minute interview with one engineer.
• Technical interview: a 1-hour 30-minute system design interview with two engineers.
• Product interview: a 1-hour product interview with a product manager.
• Final interview: an interview with our engineering lead and a team lead.

I was stopped after the pair programming interview.

Define the interface for a value conversion service. Implement an example of a conversion query. Cache it.

Yeah, it looks good, but should we do anything else? Yes, but don't you think there is something that can be done differently? (variation of this same question for about 10 minutes)

Yeah, the function you are calling is not thread-safe. How could we improve it?

But don't you think it's inefficient? Is there any other way we could do it? (Variation of the same question for about 10 minutes)

Yeah, it is not thread-safe, you can call it just a certain number of times. What would you do? There is some feature in the language, but I'm trying to see what you think.