LilOS is a microkernel built for the purpose of 1) learning C and 2) gaining practical understanding of operating systems and the hardware-software interface. For details about the kernel itself, see Daniel McCarthy's original PeachOS.
All development of this kernel was done in a VM of Ubuntu 24.04 LTS x86_64. I used Gnome Boxes, but if you're on Mac or Windows, try VirtualBox. On your VM application of choice, create a new virtual machine out of a Ubuntu 24.04 LTS x86_64 image. I would recommend allocating 25 GB of disk space for developing in the VM, or 12 GB if you intend only to run it.
It is recommended that you go into Settings > Power > Make sure 'Screen Blank' is set to 'Never'.
Then, create a directory named src/ in your Home folder. We're going to move the downloaded Binutils and GCC source folders into here. This repo has been tested with versions GCC 10.2.0 and Binutils 2.35.1. Later versions may have breaking changes.
Go to the binutils GNU mirror site, scroll down to binutils-2.35.1.tar.gz, and click on it to download. You may have to double-click the .tar.gz file to extract. Then move your downloaded binutils-2.35.1 folder into the /home/src directory you created above.
Go to the GCC GNU mirror site GCC's source code. Click on gcc-10.2.0 > gcc-10.2.0.tar.gz. It may take a few minutes to download. Like Binutils, double-click the .tar.gz file and move gcc-10.2.0 into /home/src.
Finally, run the one-time command ./setup.sh to finish setting up your Ubuntu environment. It may take a while. It automates the steps outlines in OSDev Wiki's GCC Guide, plus creating a necessary mount point for building the kernel.
Use the terminal to navigate the the workspace root and run ./build.sh. Then cd bin and run lilOS using qemu-system-i386 -hda ./os.bin. You can type in the terminal, and if you shut down the OS and edit the files inside lilOS/programs/, you can change the text that appears on screen. You can also type!
Development of LilOS is on indefinite hiatus. I've shifted my focus to a new kernel project to test my knowledge on a more independent kernel project, so it's unlikely lilOS will see further development.