MinOS

MinOS is the absolute simplest implementation of an operating system kernel that just prints out "Hello, World!", written in x86 assembly. The kernel source code is in kernel.asm, and there are also utilities to build an ISO.

Build and run

Build binary:

nasm -f elf32 kernel.asm -o kernel.o
ld -m elf_i386 -T linker.ld -o kernel.bin kernel.o

Build a bootable ISO:

mv kernel.bin ./iso/boot/
grub-mkrescue iso -o minos.iso

Finally, you can take this iso and boot it, to test, we can use qemu:

qemu-system-x86_64 -cdrom minos.iso

Of course you should have these tools installed first:

sudo apt update
sudo apt install nasm qemu-system-x86 grub-common grub-pc-bin xorriso