Guil‑OS is a lightweight, modular, and fully hand‑crafted operating system designed for retro x86 hardware.
It focuses on clarity, maintainability, and hardware longevity, offering a clean architecture that avoids bloat and embraces simplicity.

This project is both a technical playground and a manifesto for ethical, ecological computing:
reviving old machines, reducing e‑waste, and proving that elegant software can run on modest hardware.

• Custom GDT
• Custom IDT (256 entries)
• PIC remapping
• IRQ0 (timer) + IRQ1 (keyboard)
• Clean interrupt handlers
• Fully 32‑bit environment

• Scancode → ASCII translation
• Shift / Ctrl / Alt state tracking
• Backspace, Enter, Tab
• Extended keys (0xE0)
• Arrow keys (left/right/up/down)
• Circular input buffer
• No polling — fully interrupt‑driven

• 80×25 VGA text mode
• Custom text buffer
• Cursor management
• Line editing (backspace, redraw)
• Shell input system

• Clear separation of kernel, drivers, and userland
• Minimal dependencies
• Clean, readable assembly
• Designed for future scripting integration (Lua, Perl, Tcl)

• Designed to run on:
  • Pentium / 486 / 386
  • Laptops with PCMCIA
  • ISA/PCI network cards (RTL8139, NE2000, 3Com 3C562 planned)
• Boots from BIOS with no external OS

• NASM
• QEMU or real hardware
• A bootloader (included or external)

nasm -f bin kernel.asm -o kernel.bin

qemu-system-i386 -kernel kernel.bin

Flash to USB or floppy image and boot directly.

• Finalize keyboard driver
• Add TTY switching (Alt+F1/F2/F3)
• Improve shell input
• Add timer‑based features

• Full network stack (GF‑NetStack)
• PCMCIA support (3Com 3C562)
• Wi‑Fi support (Linksys WPC11 v4, RTL8180L)
• Minimal POSIX‑like API
• Lua/Perl scripting engine
• Graphical terminal
• Lightweight window system

Guil‑OS is built on three principles:

Every component is small, isolated, and understandable.

Readable code > clever hacks.
Future contributors should feel at home.

Old hardware deserves a second life.
Software should empower, not consume.

Contributions are welcome!
Whether you want to fix a bug, add a driver, or improve documentation, feel free to open an issue or submit a pull request.

MIT License — simple, permissive, contributor‑friendly.

Guillaume Foisy — Architect and technical lead of Guil‑OS
Passionate about retro hardware, modular design, and ethical computing.