I'm an experienced developer from startups and recently as an independent contractor, and would also like to better understand what kind of tangential consultin

I'm an experienced developer from startups and recently as an independent contractor, and would also like to better understand what kind of tangential consulting opportunities are out there. My hunch is that most are really really niche, i.e., "we need someone who can tune a massive Postgres cluster to run at peak performance next week". I'm really good at doing code audits and helping improve their style but I haven't found a way to package that into a consulting service.