GemOS

GemOS is a lightweight, customizable, extensible operating system based on Linux built by your own machine. It constructs a minimal, UEFI-bootable ISO image using the host's kernel and a static BusyBox binary.

Note

This project is still a work in progress. Contributions to improve hardware compatibility are highly welcome!

Features

• Minimalist: Extremely small footprint, focusing only on essential components.
• UEFI Support: Built-in support for UEFI booting via GRUB.
• Extension System: Modular design allowing for easy addition of features (e.g., disk utils installation).

Prerequisites

To build and run GemOS, you need the following tools installed on your system:

• curl: To download packages.
• xorriso: For ISO image creation.
• grub-common: Specifically grub-mkimage for creating the EFI bootloader.
• mtools & dosfstools: For manipulating EFI system partition images.
• binutils: For strip to minimize binary sizes.
• (Optional)qemu-system-x86_64 & ovmf: To run the resulting ISO in a virtual environment.

Ubuntu/Debian

sudo apt update
sudo apt install curl xorriso grub-common mtools dosfstools binutils qemu-system-x86_64 ovmf

Arch Linux

sudo pacman -S curl xorriso grub mtools dosfstools binutils qemu-desktop ovmf

Getting Started

Build the ISO

Simply run the following command to build the ISO:

make build

The output will be located at build/gemos.iso. With no extensions, its size could be about 40MB.

Run in QEMU

To test GemOS in a virtual machine:

make run

Note: This requires OVMF to be installed at /usr/share/ovmf/x64/OVMF.4m.fd (standard on most distros).

Cleanup

To remove build artifacts:

make clean

To remove all downloaded files as well:

make clean-all