I don't work for a tech company unfortunately, however I work in a very big and "worldwide-well-known" company. The thing is that, as other people said before me, it depends.
I'm talking about the dress code the company has, usually kinda free in the limits of decency (you cannot just go to work almost naked you know?) and hygiene, or the employers themselves, I mean, your look is the first thing they see and the first they evaluate even before to proceed with the interviews.
Anyway, I think that if an employee worth the efforts, making an eventual good impact on the company's profit thanks to his work, the look is definitely put aside. This is what I learned in my experience working for a big company.
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