NoOS

NoOS is a minimal 64-bit operating system kernel written entirely in Rust, designed as an educational exploration into low-level systems programming. Built from scratch with a GRUB2 bootloader and Multiboot2 compliance, NoOS demonstrates how modern memory-safe languages can be applied to bare-metal development where every byte matters.

Key Features:

• 64-bit Long Mode: Full x86_64 architecture support with proper CPU mode transitions from 32-bit protected mode to 64-bit long mode
• GRUB2 Bootloader: Multiboot2-compliant kernel loading with structured boot information parsing via the multiboot2 crate
• VGA Text Driver: 80x25 color text mode with spinlock-protected output, cursor control, and scrolling
• Keyboard Input: PS/2 keyboard driver with interrupt handling, scancode queue, and US layout support
• Interactive Shell: Command parsing framework with input buffer and backspace support
• Memory Safety: Rust’s ownership model eliminates entire classes of bugs common in traditional kernel development

What makes NoOS unique is its educational clarity. The modular codebase separates concerns across boot/ (assembly bootstrap), kernel/ (Rust kernel), and config/ (linker scripts), revealing how each piece contributes to the boot process: from Multiboot2 header validation through page table setup to the final Rust entry point.

The kernel leverages modern Rust ecosystem crates like x86_64 for hardware abstractions, spin for spinlock mutexes, and pc_keyboard for scancode decoding—all running without a standard library or heap allocation.

Read more about NoOS architecture