I found a well-known online OS development guide and want to understand what it covers before diving in. Does it walk through building a small operating system from scratch, or is it mainly a collection of theory and implementation references? Can one person realistically create a mini operating system by following it? Since the material is organized as a wiki with many interconnected pages, is there a recommended roadmap or sequence with prerequisites? Also, what background should I have first—strong C skills, assembly, computer architecture, memory management, or even compiler construction?
3 Answers
It covers both the theory and practical details behind major OS components, including bootstrapping, interrupts, memory management, scheduling, and filesystems. However, it is not one perfectly linear course that takes you from start to finish. Begin with the introductory material and basic kernel tutorials, then follow the pages related to the next feature you want to implement. The beginner guidance is also worth reading early because it points out common mistakes.
You should be comfortable with C, basic data structures, pointers, and debugging. Some assembly is necessary for startup code, context switches, interrupt handlers, and other CPU-specific work. It also helps to understand computer architecture, memory, binary representation, linking, compilers, and how programs interact with hardware. You do not need to write your own compiler before starting; an existing compiler and linker are standard tools for OS development.
Compiler construction is a valuable project because it teaches parsing, transformations, memory concepts, and how languages become machine code, but it is not required for OS development. You can use existing toolchains and still learn a great deal. OS projects take so long because even a seemingly small feature often requires several layers of low-level code, hardware-specific behavior, testing, and debugging.
A solo developer can definitely build a small hobby operating system. The realistic expectation is important, though: a basic bootloader or kernel that displays text is very different from a usable OS. Once you add hardware support, processes, virtual memory, filesystems, drivers, debugging tools, and a user interface, the project can easily take years. You do not need a large team, but you do need patience and a willingness to learn as you go.
I’ll study C and assembly first. I’m also interested in learning how to build a compiler—would that make me a better programmer, or is it mostly optional for this project? And why does even a small operating system take so long to build?