If an applicant says they have 3 -5 years of experience but have nothing to show for it, I would be suspicious too.
I'm not sure I would consider not having Github, Codepen, etc as a red flag. It's possible they used some internal VCS. And I'll admit I've never used Codepen myself.
But having no personal projects to show seems a little unforgivable to me. How is an employer supposed to gauge your suitability for the job if you have nothing to prove your level of experience? Even if your code is crap, at least the employer knows what to retrain you on.
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