As someone who has done a lot of interviewing over the past few years, I concur with some points. We give candidates very strict guidelines on what we expect from the submission, both in terms of scope and style, so ignoring that is definitely a red flag.
That said our exercise is a lot more manageable since it's a task that can be done without any external libraries (this is in fact a requirement) in anywhere between 2-6h depending on skill level and attention to detail.
Hey Michael, would you like to share more details about your test case?
The external library is intentionally part of our requirement. There are a ton of libraries to validate IBANs. How will the candidate chose between them? Will they use one at all or implement an already solved problem again reinventing the wheel, etc.
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