Iridium is a hobby operating system written from scratch in C, with a microkernel architecture for the x86_64 platform. It is inspired by Fuchsia's kernel object and capability system for handling processes' access to resources.
Building Iridium does not require many tools, just make, and an x86_64-elf-gcc cross compiler (Stock gcc on x86_64 may work, but is not recomended as this is not a linux clone). Additionally, grub is used to produce bootable disk images, which can be used in any x86_64 emulator of your choice.
To build the OS and init process, run make. make iso generates a bootable disk image named grub.img.
If you have qemu-system-x86_64 installed, you can test the OS easily using make emu.
Limited kernel documentation is available in the docs/ folder, outlining available system calls and how the OS works. However, the documentation is incomplete and the API is subject to change without warning.