Run eframe full screen on OpenGL ES for embedded (i.e. no windowing system or compositor)?

[barries]

Is there a backend, configuration or example project that shows how to integrate egui, and ideally eframe (since that's what we're using for Linux and Windows), using the GPU more-or-less directly, and receiving touch screen & keyboard input directly from the respective kernel devices?

For context: we have an eframe GUI that runs very nicely on Windows and Linux; it's a single window that will run fullscreen-only on a tablet PC (e.g. "kiosk mode"). We're building the OS in buildroot and trying to minimize the SBOM--this is a medical device and SBOM, license and vuln management are all mandatory--and simplify the overall system (fewer daemons/services, shallower library stacks, etc. to reduce bug volume and maintenance burden).