Those are good ideas.
The folks with a mutual interest are probably on StackOverflow. It's too bad that SO doesn't encourage social interactions. The topic has been discussed a few time on Meta, and they're very explicit about it. They might even be right that it will alter who they are, but I wish they could find a way to add some such element.
SO made a specific portal, probably it is used by those who hate Linkedin stackoverflow.com/jobs
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