I dunno. We started doing something like that at my company (we actually use the plain Accept/Content-Type headers, so "application/vnd.mycompany.service.v1+jso

I dunno. We started doing something like that at my company (we actually use the plain Accept/Content-Type headers, so "application/vnd.mycompany.service.v1+json") and it's been a giant pain. Routing based on headers sounds cool, but basically no backend OR frontend frameworks support it well. Even if they say they support, there are bugs or weird traps to fall into. Path versioning is just so much easier for everyone.