An operating system in 1000 lines

Hey there! In this book, we’re going to build a small operating system from scratch, step by step.

You might get intimidated when you hear OS or kernel development, the basic functions of an OS (especially the kernel) are surprisingly simple. Even Linux, which is often cited as a huge open-source software, was only 8,413 lines in version 0.01. Today’s Linux kernel is overwhelmingly large, but it started with a tiny codebase, just like your hobby project.

We’ll implement basic context switching, paging, user mode, a command-line shell, a disk device driver, and file read/write operations in C. Sounds like a lot, however, it’s only 1,000 lines of code!
↫ Seiya Nuta

It’s exactly what it says on the tin.