Just look over recent ShowHN entries and imagine what categories to sort each entry in will show that your categories have to be so broad as to be useless, or t

Just look over recent ShowHN entries and imagine what categories to sort each entry in will show that your categories have to be so broad as to be useless, or too specific. e.g. "Development", "Promotion", "SaaS". At least with my own project I know what tags to suggest: "git", "DNS". But where I'd file it otherwise I'd have no idea.