Chelidae is a modified operating system based on the MIT xv6 (x86) kernel, extended with a custom graphical user interface and window manager.

Toolchain & Requirements

The Chelidae build system is designed specifically for Linux environments (native Linux or WSL2).

Required Packages (Linux)

• gcc with 32-bit support (gcc-multilib)
• binutils with i386 support
• qemu-system-i386 for emulation
• make for build automation
• golang (version 1.20 or newer) for build utilities
• python3 with Pillow for asset processing

Installation (Debian/Ubuntu)

sudo apt update
sudo apt install build-essential qemu-system-x86 golang python3 python3-pip
pip3 install Pillow

Build and Execution

The Makefile automates the full build pipeline for the Chelidae kernel, userland, and disk images.

Compilation

Build the kernel, user programs, and filesystem images:

make -j$(nproc)

Running in QEMU

Launch Chelidae using QEMU:

make run

Asset Conversion Scripts

convert.py

Converts window UI icons (such as close and minimize buttons) from PNG files into C arrays.

python3 convert.py

font.py

Converts a TrueType font (fonts/font.ttf) into bitmap character arrays for text rendering.

python3 font.py

convert_icons.py

Converts desktop application icons from PNG files into C arrays. Place 48x48 PNG icons inside the app_icons/ directory.

python3 convert_icons.py

Project Structure

• kernel/: xv6-based kernel source code (scheduler, memory management, filesystem, and GUI logic)
• user/: User-space applications and supporting libraries
• include/: Shared header files
• icon/: PNG assets for window UI elements
• app_icons/: PNG assets for desktop applications
• fonts/: TrueType fonts used for text rendering
• scripts/: Go and Python scripts used during the build process

Build Process Analysis

1. convert.py scans icon/*.png and generates icons_data.c
2. font.py converts fonts/font.ttf into character.c and character.h
3. convert_icons.py scans app_icons/*.png and generates app_icons_data.c and app_icons.h
4. GCC compiles the Chelidae kernel and user programs using -m32 for the i386 architecture
5. Linker scripts (kernel.ld) define the final kernel memory layout
6. The mkfs utility generates fs.img containing user-space programs
7. dd combines the bootloader and kernel into Chelidae.img

License

MIT License.

Chelidae is derived from the MIT xv6-public source code and remains compatible with the original xv6 license.