A functioning OS built from scratch. This was done using QEMU and RISC-V toolchain, most of this was a learning process to fully understand the inner workings of an OS. Not everything is complete or 100% working, although there are many features that are finished.
A list of current features:
SBI/Bootloader
Locking
Privilege escalation
MMU
PCI
V/IO
Basic GPU, Block, and Input drivers
Scheduling (basic CFS)
User processes
In progress:
Minix3 FS
EXT4 FS
VFS
USB