Redox OS is a complete Unix-like operating system written from scratch in Rust — not Linux with Rust components bolted on, but a from-scratch microkernel kernel and userspace, including its own C standard library replacement and its own ZFS-inspired filesystem. The community has been active since 2015, the work is predominantly MIT-licensed, and 2026 has been its strongest year yet: an Xfce desktop port, a new scheduler, io_uring-style I/O, and a €50,000 NLnet grant. It is not a daily driver yet — and this article keeps that honesty front and centre.
The Rust OS: Redox OS, an operating system written from scratch in Rust
If Strata attacks the cloud and AnyPS5 attacks the console, Redox OS attacks the foundation underneath both: the operating system itself. Redox describes itself as "a complete Unix-like general-purpose microkernel-based operating system written in Rust." It is not Linux with Rust components bolted on. It is a from-scratch kernel and userspace, including its own C standard library replacement (relibc, written in Rust), its own ZFS-inspired filesystem (RedoxFS, with checksumming for data integrity), drivers that run in userspace rather than in the kernel, and capability-based security, where a process can only touch resources it holds a capability for. The community has been active since 2015, the work is predominantly MIT-licensed, and the project runs a Redox Summer of Code programme every year since 2018.
Why Rust, in one paragraph: most security vulnerabilities in C and C++ operating systems are memory errors — buffer overflows, use-after-free, dangling pointers. Rust's compiler eliminates whole classes of these at compile time, without a garbage collector. A microkernel shrinks what runs in privileged mode even further: when a driver crashes in userspace, it does not take the kernel with it. The combination is the pitch — a much smaller attack surface than Linux, with modern architecture and no legacy cruft.
Who builds Redox, and what happened in 2026
Redox is community-built, funded by donations (Donorbox, Patreon, crypto, merch) and, since June 2026, by a €50,000 grant from the NGI Zero Commons fund and NLnet for "Virtualized Redox" — four part-time developers for twelve months, working on virtio networking, TCP/IP offloading and virtiofs file sharing, aimed at running Redox as a web server and microservices runtime. The 2026 progress, month by month:
| When | What landed |
|---|---|
| January 2026 | Self-hosting milestone reported in the project's retrospective (building Redox on Redox); work began on Redox's own Intel graphics driver |
| February 2026 | Cargo and the Rust compiler running on Redox itself |
| March 2026 | Vulkan and Node.js working on Redox |
| April 2026 | New CPU scheduler work (about 1.5x faster in heavy tasks, per the project); an AI policy forbidding contributions made using large language models |
| June 2026 | Xfce desktop ported — a major desktop usability milestone; COSMIC application support; NLnet grant announced |
| July 2026 | EEVDF-based scheduler merged (2.6x throughput, 782x fairness improvement, per the project's figures); installer improvements; GTK3 backend for the Orbital desktop, fractional scaling, USB gamepads |
| August 2026 | Ring-buffer communication API similar in concept to Linux's io_uring; initial NUMA support; initial multi-core support on ARM64; QEMU running on Redox (without hardware acceleration, so slow); dual-boot installation from Linux; IPC overhead down about 5% (project figure, no published method or baseline); smaller kernel binary |
| September 2026 | Further performance improvements (Phoronix, October 25); JIT compiler optimisations; external display hot-plugging; improved page-fault handling; uutils 0.11 and SDL2 integration; Clang port work |
The August report's headline number needs the same honesty as Strata's benchmarks: coverage reported the project's own benchmark cutting NVMe read/write overhead by 14 to 15 times with the new ring-buffer API, while independent coverage notes no published benchmark with method has been released yet, and the API helps only drivers that adopt it. It is not a compatibility layer for Linux io_uring software. Similarly, the 5% IPC reduction is the project's own figure and should not be read as a 5% overall performance gain — though on a microkernel, where every driver and service pays the IPC tax, single-digit reductions add up.
Redox performance and requirements
Redox is light by design: the minimal image is under 50 MB, and the desktop variant uses under 512 MB of RAM. An independent review of Redox 0.9.0 measured idle RAM at 480 MB against 800 MB or more for Ubuntu 24.10, syscall latency at 1.2 microseconds against 2.1, and POSIX compliance around 80% against 95% or more for Linux — reviewer figures from late 2025, not project claims, and the project has moved on since. Hardware support covers Intel and AMD (32- and 64-bit), ARM 64-bit and RISC-V; it boots on real hardware including Raspberry Pi 4 and RISC-V boards, from NVMe, SATA, IDE and USB, with full-disk encryption. The safe way to try it is a virtual machine on your existing Windows or Linux system using the project's daily images — the Linux dual-boot path is documented, but no verified Windows dual-boot procedure has been published, so real-hardware installation is only for people ready to rebuild a bootloader if something goes wrong.
One more Rust OS deserves a line: Asterinas 0.18 (June 9, 2026) takes the opposite design — a "framekernel" that runs in a single address space like a monolithic kernel for speed, while Rust's ownership model partitions it into a privileged framework and unprivileged services that must be pure safe Rust. It is backed by Ant Group, Intel, Peking University and SUSTech, and its OSDK toolchain builds Rust kernels with Cargo-like ergonomics. Redox is the general-purpose desktop bet; Asterinas is the server-kernel bet. Neither project aims to replace Linux — both prove Rust can build entire operating systems safely and fast, which is the point the industry is watching.
The honest limits of the Rust OS bet
Redox is not a daily driver yet, and its own coverage says so plainly. No Steam, no Office, no enterprise stacks; spotty peripherals; a tiny userbase means less help when something breaks. The desktop exists (Orbital, plus COSMIC apps and the Xfce port), media playback works, NetSurf browses, and many games and demos are ported — but the ecosystem gap against Linux, let alone Windows, is enormous. Redox does not threaten Microsoft's revenue this year. What it threatens is the assumption that operating systems must be written in C and must carry forty years of legacy. That assumption is worth far more than one year's sales.
Linux and Windows: where Redox fits
Redox does not ask you to abandon your current system to try it. It runs in a virtual machine on Windows or Linux, its dual-boot installation from Linux is documented, and it boots bare-metal on x86-64, ARM64 and RISC-V hardware. What it does not yet offer is a verified Windows dual-boot procedure — that path is undocumented, so treat real-hardware installation as an experiment, not a migration.
| Redox OS | Linux | Windows | |
|---|---|---|---|
| Kernel | Microkernel, written in Rust | Monolithic, written in C (with Rust entering the kernel) | Hybrid NT kernel, written in C/C++ |
| Licence and cost | Mostly MIT, free | GPL, free | Proprietary, paid licence |
| Desktop RAM (idle) | Under 512 MB (480 MB measured on 0.9.0) | 800 MB or more (Ubuntu 24.10, reviewer measurement) | Several GB on Windows 11 |
| Security model | Memory safety by construction + capabilities + userspace drivers | SELinux / AppArmor on top of a C kernel | Defender, virtualization-based security, signed drivers |
| Software ecosystem | Small: Orbital, COSMIC apps, Xfce, uutils, SDL2, NetSurf, many small ports | Enormous: servers, desktops, Android, Steam via Proton | Largest commercial software and game catalogue |
| Best for today | Experimenting, learning Rust systems programming, secure embedded ideas | Daily driving, servers, development, gaming via Proton | Commercial software, mainstream gaming, enterprise |
The through-line: Windows and Linux are not going anywhere, and this article is not predicting their death. What Redox proves is narrower and more important: an operating system can be written without C, with memory safety built in rather than bolted on, and it gets measurably better every month. The giants still own the commercial software catalogues and the enterprise contracts — but the assumption that operating systems must carry forty years of C legacy is no longer the only option.
Also in this series: Strata runs a 125B AI model on a gaming PC, and AnyPS5 turns PS5 games into native PC programs.
Can Redox OS replace Windows or Linux today?
No — not as a daily driver. It is best as a virtual machine or a secondary system for developers and enthusiasts. The ecosystem gaps (no Steam, no Office, no enterprise stacks), spotty peripherals and small userbase are real. Its value today is as proof that a memory-safe, from-scratch operating system works, and as a platform that gets measurably better every month.
How do I try Redox OS safely?
In a virtual machine on your existing Windows or Linux system, using the project's daily images. The Linux dual-boot path is documented, but no verified Windows dual-boot procedure has been published — real-hardware installation is only for people ready to rebuild a bootloader if something goes wrong.
What is Asterinas?
Asterinas 0.18 (June 9, 2026) is a second Rust operating system that takes the opposite design from Redox: a "framekernel" that runs in a single address space like a monolithic kernel for speed, while Rust's ownership model partitions it into a privileged framework and unprivileged services that must be pure safe Rust. It is backed by Ant Group, Intel, Peking University and SUSTech. Redox is the general-purpose desktop bet; Asterinas is the server-kernel bet.
Sources
- Redox OS August 2026 update: https://windowsforum.com/news/redox-os-adds-io_uring-like-ring-buffers-initial-numa-support.446021/
- Redox OS news archive: https://www.phoronix.com/search/Redox+OS
- Redox OS official site: https://www.redox-os.org/
- The Rust/Linux ecosystem map (Asterinas 0.18, Redox Xfce port): https://www.fosslinux.com/157773/the-rust-linux-ecosystem-complete-map-guide.htm
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