Dive Deep into OS Development with This Abandoned Yet Valuable Step-by-Step Tutorial

For developers curious about the foundational layers of computing, building an operating system from scratch remains the ultimate educational rite of passage. While many academic courses drown students in theory, cfenollosa/os-tutorial takes a radically practical approach—even if its creator now flags it as "abandoned" with unresolved technical issues.

Why Skip Theory? A Pragmatic Philosophy

The project explicitly rejects traditional pedagogy, arguing that "excessive theory is worse than no theory" after college. Instead, it offers:
- Micro-lessons (5-15 minutes each) that build sequentially from bare-metal booting
- Zero pre-built kernels—you write every component yourself
- Goal-oriented milestones like mastering interrupts, memory management, and processor mode switches

As the README states:

"You can do it! Start with the first folder and go down in order... The 'why' is as important as the 'how'."

The Journey: From Assembly to a Tiny OS

The tutorial’s progression mirrors historical computing evolution:
1. Booting sans GRUB (Mastering the 512-byte boot sector)
2. 32-bit protected mode (Escaping legacy constraints)
3. C-language transition (Bridging ASM to higher-level logic)
4. Hardware interfacing (Screen/keyboard I/O via interrupts)
5. Libc groundwork (Custom runtime for future features)

Later goals—like filesystems, shells, and user modes—remain aspirational but illustrate the blueprint’s ambition.

Why This Still Matters in 2023

Despite its archived status, the repo attracts forks and fixes, proving its utility. For modern engineers, it delivers:
- Context for containerization/virtualization: Understand hardware abstraction origins
- Cybersecurity fundamentals: Learn how memory protection and interrupts guard systems
- Minimalist design inspiration: Build complexity from simple primitives

Proceed—But Wisely

The author cautions newcomers to pair this with "modern, authoritative sources." Yet for hands-on learners craving visceral understanding of what happens between power on and printf(), these bite-sized labs remain potent. As one contributor noted: "Breaking things is the best way to verify understanding"—a mantra worth embracing in systems programming.

Ready to write your first bootloader? The journey begins with three instructions: mov, jmp, and persistence.