Some kernel-level code that runs at system boot. I was experimenting with this stuff in my free time in 2018, but have moved on (and if I am to try this again, I would wirte it in Jiyu, not C). Recommended environment is Qemu with a VMware SVGA adapter (see run.bat). An appropriate i686-elf toolchain with Qemu and nasm can be found here. Just extract the zip to the root folder of project and run build.bat.
There is an example of what this project looks like in this Tweet.