Rust OSDev Operating System Development in Rust

This Month in Rust OSDev: December 2025

Published on (edited by @phil-opp)

Welcome to a new issue of "This Month in Rust OSDev". In these posts, we give a regular overview of notable changes in the Rust operating system development ecosystem.

This series is openly developed on GitHub. Feel free to open pull requests there with content you would like to see in the next issue. If you find some issues on this page, please report them by creating an issue or using our comment form at the bottom of this page.

Announcements, News, and Blog Posts

Here we collect news, blog posts, etc. related to OS development in Rust.

Infrastructure and Tooling

In this section, we collect recent updates to rustc, cargo, and other tooling that are relevant to Rust OS development.

No content was submitted for this section this month.

rust-osdev Projects

In this section, we give an overview of notable changes to the projects hosted under the rust-osdev organization.

bootloader

Maintained by @phil-opp and @Freax13

The bootloader crate implements a custom Rust-based bootloader for easy loading of 64-bit ELF executables. This month, we merged the following changes:

Thanks to @spencer3035, @Taxrosdev, and @oxyzenQ for their contributions!

ovmf-prebuilt

Maintained by @nicholasbishop and @phil-opp

The ovmf-prebuilt project provides pre-built edk2 releases to make it easier to set up OVMF. We merged the following improvement this month:

Thanks to @fogti for their contribution!

uefi-rs

Maintained by @GabrielMajeri, @nicholasbishop, and @phip1611

uefi makes it easy to develop Rust software that leverages safe, convenient, and performant abstractions for UEFI functionality.

We merged the following PRs this month:

Thanks to @seijikun and @Virv12 for their contributions!

Other Projects

In this section, we describe updates to Rust OS projects that are not directly related to the rust-osdev organization. Feel free to create a pull request with the updates of your OS project for the next post.

valibali/cluu

(Section written by @valibali)

CLUU’s kernel has transitioned from a feature-oriented hobby kernel to a strict L4-style microkernel that provides mechanisms only.

  • The kernel surface is now intentionally minimal, limited to scheduling, memory management, IPC, interrupts, token verification, and syscall dispatch.
  • All system policy, including filesystems, drivers, and services, has been moved entirely to userspace.
  • Implicit privilege has been eliminated and replaced with an explicit, cryptographically verified token-based authority system.
  • Every privileged operation now requires visible, auditable authority, with no ambient permissions or global namespaces.
  • IPC has become the only communication primitive, implemented as deterministic synchronous rendezvous.
  • The scheduler has been redesigned as an O(1) priority bitmap scheduler with predictable behavior and clear separation of mechanism and policy.
  • Memory management now enforces per-process address spaces, validated user pointers, and lazy allocation via page faults.
  • The syscall interface has been reduced to seven syscalls, with all privileged actions funneled through a single token-guarded entry point.
  • The kernel is now fully unit-tested, smaller, stricter, and architecturally stable, enabling future development to proceed almost entirely in userspace.

Join Us?

Are you interested in Rust-based operating system development? Our rust-osdev organization is always open to new members and new projects. Just let us know if you want to join! A good way for getting in touch is our Zulip chat.

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