alt Hacker Newsit could be anything that just allows social connection between people that are doing the same job in the same geographic region but are largely invisible to one another.
i'd try not to be prescriptive about it, but it could cover anything from a light 'random chat' channel to vent about petty workplace annoyances, 'tips and tricks' for success, or more serious channels to talk about workplace safety/conditions/unionization
But if it's a gig, where's the workplace? E.g. if all the domestic builders in my town got together, who would they unionise against? They're not employed; that's not a gig.