EFI started as a boot loader solution for Intel Itanium systems. It has grown into UEFI, a boot loader solution for multiple architectures.
However, in my opinion, UEFI is an operating system. It has driver, service, and app models. If you don’t load another OS (eg, Windows, Linux) , and stay in UEFI, the UEFI Shell is pretty much like early MS-DOS: a shell, a bunch of command line tools, and a handful of full-screen tools (edit, hexedit). UEFI is called “the new DOS” for a reason… MS-DOS didn’t have Python either. The main thing missing is an EFI equivalent to DEBUG.COM. 🙂
Now there are a handful of new UEFI-centric OSes being created. It appears they’re mostly hobbyist, educational projects. There may be others, these are the only ones I know of so far:
I look forward to future academic research in this area. I am wondering if there are any existing hardware vendors who’re using UEFI as the only software stack, not using other embedded OSes? Someone needs to do some performance testing to see how it compares to eLinux/Android/NanoBSD/etc.