Velvet

 lylythechosenone/velvet

Velvet is the third iteration of my custom kernel. It is built entirely in Rust (with a bit of inline assembly), and it follows the core principles of speed, memory efficiency, and simplicity. It aims to be fast with as few compromises as possible. It is currently in early development, and supports only AArch64¹. However, x86_64² support is also planned.

Philosophy #

Velvet is built to be so simple that it can be understood by anyone with a basic understanding of the architectures. The goal is not to become a large monolithic kernel, like many of the current ones³. Instead, the kernel should only grow exactly as much as it needs to in order to function. For this reason, the kernel itself includes almost no drivers. Currently, the only driver is a dummy UART driver for use inside of QEMU. Anything else is loaded as a user-space process, given special access permission to specific parts of the device. This allows for easier maintenance, as well as more security and transparency for the user, who has full control over what drivers are used.

It is also built to minimize compromise. Whenever possible, the chosen solution is one that both uses minimal memory and takes advantage of the speed of modern hardware. The kernel is built with SMP in mind, and is designed to be able to scale to as many cores as possible. It is also designed to be able to run on as little as 1 MiB of RAM (although this is not recommended).

Why? #

In my eyes, there is a lack of innovation in the operating system space. Many kernels are stuck on old algorithms and designs, reading the old designs and not bothering to put in the critical thinking required to improve them. In velvet, I aim to try everything. Many of the algorithms within it are already heavily customized versions of existing algorithms, and some are entirely original. I only settle on something when I’m sure that it’s the best possible solution.

Where does it run? #

Currently, velvet has only been run in a virtual machine. However, it could theoretically run on any standard-compliant AArch64 machine. I also plan to add support for Apple Mac devices, although these are somewhat difficult to support due to their locked-down ecosystem. Once x86_64 support is added, it will be runnable on any standard-compliant x86_64 machine without issue.

When will it be ready? #

Velvet is currently in early development, and is not ready for use. However, I am working on it as much as I can, and I hope to have a usable version ready within a few years as a maximum.