The project's README from github.com/moturus/motor-os. As one markdown file: README.md.
Motor OS is a simple, fast, and secure operating system built for the cloud. It targets virtualized workloads such as web serving, serverless computing, and edge caching, and avoids the overhead a general-purpose OS carries when it runs inside a VM.
It is written entirely in Rust, from the kernel to the shell, and its system interface is Rust, not C. It runs as an x86-64 KVM guest under QEMU, Cloud Hypervisor, and Firecracker.
This README is a summary. The details are on the website, motor-os.org: the architecture, the process model, the filesystem, networking, terminals, the commands and programs, the toolchains, and how to develop for Motor OS in Rust and in C/C++.
At the moment, most virtualized production workloads run Linux. Linux has many advanced features that in many situations make it the only reasonable choice, but several things make it less than ideal, in theory, for some virtualized workloads:
A new operating system built from the ground up with a focus on virtualized workloads can be made much simpler and more secure than Linux, while matching or exceeding its performance and efficiency.
What Motor OS does differently:
fork, no signals, no pseudo-terminals, no
users. Processes carry an immutable capability word, and three roles derived
from it (System, Interactive, None) drive filesystem permissions.Motor OS is a microkernel-based operating system. The kernel, about 18,600
lines of no_std Rust with four syscalls, manages address spaces, threads,
scheduling, capabilities, and wait/wake objects. Everything else runs in
userspace: sys-io owns the VirtIO block and network devices, the journaling
filesystem (Motor FS), and the networking stack (moto-netstack); sys-init
starts services; sys-tty drives the serial console; strobe collects logs
and metrics; dns-resolver resolves names; russhd serves SSH. A per-process
runtime object, rt.vdso, implements the system interface that Rust's
standard library calls through the small moto-rt crate.
What works today:
x86_64-unknown-motor is a Tier-3
Rust target); Tokio and mio, rustls, hyper, axum, and russh work.Cargo.toml and Cargo.lock,
byte-identical binaries; but offline, with every dependency fetched once,
checked, and approved before it is built), plus Gears, curl, mdbg, and the
test suites.Motor OS is approaching beta quality. Its development started in 2021, and in 2026 it went through weeks of systematic AI-assisted review and hardening, of the networking stack in particular. Networking is considered ready for production use within its supported feature set; the rest of the system is exercised daily by the full test suite, by long soak runs, and by the website, which is served from Motor OS VMs. There has been no independent security audit yet.
See docs/build.md for the build instructions, docs/tools.md for the VM scripts and the tools inside the VM, docs/toolchain.md for how the toolchain is versioned and updated, and docs/recipes/index.md for examples. The website covers all of this in more detail, including the toolchains and Lorry.