Amethyst

A UNIX-like OS with functional configuration and scripting support.

Important

This project is purely meant for educational purposes. There is no effort to produce production-ready code. Expect many features to be buggy, broken or even unimplemented.

Overview

This Project consists of three main pieces of software:

a) Amethyst - The Kernel

The Amethyst kernel is a UNIX-like monolithic kernel built completely from scratch in C23 and Assembly.

This is the main part of this project. The code can be found in the init/, kernel/, drivers/ and include/ directories. Platform-specific code is located in the arch/ directory.

Features:

• Booting using the limine boot loader
• Paging, physical and virtual memory management
• Kernel heap
• UNIX-like VFS (including pseudo-filesystems like devfs (/dev) and tmpfs (/tmp))
• proper file systems like FAT32, ext2, ...
• NVMe driver
• SMP-enabled preemptive multitasking and process management
• Syscalls
• Kernel stack switching
• User mode
• PCI device identifictation & interaction
• Keyboard input
• Mouse input
• ...

Supported Architectures:

• x86_64
• riscv64 (planned)

b) Shard - A functional scripting language

Shard is a functional programming language designed for declarative builds and configuration of the Amethyst Operatiing system.

See ./shard and ./shard/README.md for more information.

c) Geode - A declarative package manager based on Shard

Geode is the package manager and build system of the Amethyst Operating System.

See its source in ./shard/geode and the package store in ./store.

Features:

• bootstrap: Build a new fully functioning system from a single configuration file [in progress]
• rebuild: Rebuild the system root on the go
• update: Pull store updates from the internet and do a full rebuild
• ...

Warning

geode is in especially early development state. To get a booting system image, please refer to commit 7029ae7 until geode is able to bootstrap the full system.

Building

Build Dependencies:

• GNU binutils
• GNU make
• gcc version >= 13 (with C23 support)
• libarchive
• python3 (versions tested: 3.11 - 3.13)

Runtime Dependencies:

• qemu

Getting an ISO

1. Clone this repository:

$ git clone https://github.com/spydr06/amethyst --recursive
$ cd amethyst

2. Build the ISO image:

$ make

Note

When compiling for the first time, bootstrapping the system can take several minutes.

Running in a VM

To run amethyst in qemu, use either the run or run-kvm make targets in order to run with or without KVM enabled.

$ make run

or (with KVM):

$ make run-kvm

Contributing

Pull requests are welcome. For major changes, please open an issue first for discussion. Make sure to update unit tests as appropriate.

Please note that this is a toy OS. Hardware support and system stability are not guaranteed.

License

Amethyst, Shard and Geode are licensed under the MIT License. See ./LICENSE for more information.

For all other parts (pci.ids, limine, libarchive, ...), their respective licenses apply. I take no credit at these projects.

Resources | Reference | Inspiration

• OSDev wiki
• OSDev Discord server
• The Linux Kernel
• Astral
• SpecOS
• PotatOS
• AsbestOS
• ...