What kind of knowledge does an engineer working on cloud services have?

Question

There is a lot of information online about "Cloud Engineers" but that term is kind of reserved for people who build service using cloud providers like AWS, GCP, Cloudflare etc. Surprisingly, there is very little information about what people who built AWS, GCP, Cloudflare etc. actually do. I think it's pretty obvious that their daily routine is different from application-focused jobs, be it frontend OR backend. So-called "Infrastructure Engineering" also is synonymous with DevOps work which I believe is again different. While I understand there is a lot of work related to physical server maintenance, someone also writes software that allows deploys to any of the cloud's services. What do you call such an engineer and what do they actually do? It would be nice to hear from people who work at the aforementioned companies or similar ones.

daviddever23box · Accepted Answer

Service-offering related metadata, and its aggregation for operational and billing purposes, is the key differentiator. “Service Engineering” would aptly describe the application layers, with “Infrastructure Engineering” handling the underlying internal provisioning of those applications.
Database management and network specializations also come into play, as well as the datacenter operations themselves (hardware provisioning and replacement, physical connectivity and other infrastructure).
None of this includes the effort required to maintain a public-facing application front-end, though it is possible to access services via an external portal which spans more than one cloud provider.