Initially, LinkedIn was just another site where you could find jobs. It was simple to use, simple to connect with others; it even had some friendly groups with meaningful discussions.
And then it gained monopoly as the “sole” professional network where you could actually land a job. If you are not on LinkedIn now, you are quite invisible in the job market. Recruiters are concentrated there, even if they have to pay extremely high prices for premium accounts. The site is horrible now: a social network in disguise, toxic and boring influencers, and a lot of noise and bloated interface to explore.
When Google decided to close their code.google.com, GitHub filled a void. It was a simple site powered by git (not by svn or CVS), and most of the major open-source projects migrated there. The interface was simple, and everything was perfect. And then something changed.
GitHub UI started to bloat, all kinds of “features” nobody asked for were implemented, and then the site became a SaaS. Now Microsoft hosts the bulk of open-source projects the world has to offer. GitHub has become a monopoly. If you don’t keep your code there, chances are people won’t notice your side projects. This bothers me.
Rant over. I hate internet monopolies.
What they’re asking for is a public portfolio.
Obviously, you can’t give them code that legally belongs to a past employer and they’re not allowed to look to avoid accusations of copyright infringement.
Especially if they do any reverse-engineering for interoperability, there must be zero suspicion that they were inspired by code they’re not allowed to use.
This is where open source contributions under permissive licenses come in.
Something shown to work in a real project is also viewed better than out of context code snippets.
When you’re essentially saying you have nothing to show them, you’re indistinguishable from someone who actually has nothing and is lying about their skills, so the onus is on the interviewers to vet you, which for various reasons may not be possible, so they’d rather just move on to someone with a clearly proven track record.