Definitely get that it works as a backend as well. I guess I am imagining a frontend-agnostic platform that is more backend-centric, rather than targeted directly for frontend web development.
Ideally I just get an endpoint from my backend-as-a-service (Supabase style) I can pop into Vercel as an environment variable, and use it as well in my moblile apps, public api, etc.
If you're already using likes of Supabase, Firebase etc. then Parse.com (RIP) was that OG BaaS but Facebook acqui-killed it. Now it's available as a open-source project and is used by several providers to provide BaaS[1].
I had used both proprietary & open-source Parse until 4 years back for several production applications but has since gone back to relational DB(pgSQL), so don't know the current status of the ecosystem.
Ideally I just get an endpoint from my backend-as-a-service (Supabase style) I can pop into Vercel as an environment variable, and use it as well in my moblile apps, public api, etc.