Does anyone have a working example of geolocating using nextjs's req.geo or 'x-vercel-ip-xxxx'?

Especially using appdir and a middleware.ts (I'm using clerk's middleware) I feel like I've tried it all, and read all the docs, and this just doesn't seem to work. I'm deployed on vercel, I have the team account, etc. Maybe I just don't understand something. The middleware should be adding the parameters to url, and I'm reading them in a route handler, but they're always undefined it seems.