Bare-metal management isn’t custom, it’s just not cloud. A TFTP server, your choice of confirmation management, your choice of image builder, probably - but not necessarily - a hypervisor, and that’s pretty much it.

This stuff isn’t hard, and it was solved well over a decade ago. Probably two at this point. It’s just been shoved down by the hyperscalers (who themselves are busily hiring for those skills).