# NoWayOS

> NoWayOS is the Single Purpose OS: a computer with nothing else to do. It builds each dedicated device from only what its one job needs, on the seL4 microkernel, in Rust.

- NoWayOS is a Single Purpose OS: an operating system built for one dedicated device's one job. Its tagline: a computer with nothing else to do.
- Single Purpose OS is the name NoWayOS gives this kind of operating system. Three things make one: it is built for one job (the image holds the application, the drivers it uses and the kernel, and nothing else: no browser engine, window system, shell, package manager or user account); it is sealed inside (each part in its own compartment, reaching only what it was granted); and it shows its working (every grant written down, every component listed, checks anyone can run). It differs from kiosk mode, which locks a general-purpose system to one app, and from a single-user OS, which limits who uses a computer.
- Each part (screen, input, network, application) runs in its own seL4 protection domain, holding only the capabilities its system description grants. Every grant is listed in a file the build checks.
- NoWayOS is written in Rust; unsafe code is allowed only in a short, reviewed list of crates.
- Status: in development and not ready for production. It runs in QEMU and on the Raspberry Pi 5; NXP i.MX8 is the intended production hardware.
- seL4 has machine-checked proofs of correctness and security for specific configurations. NoWayOS uses seL4's mixed-criticality configuration, whose AArch64 proofs are in progress, so no NoWayOS image is inside seL4's completed proofs today.
- The projects: NoWayOS (the operating system; intended licence MIT OR Apache-2.0), the Screen Compiler (React screens to native Rust at build time; MIT) and the Showcase (example kiosks for the Raspberry Pi 5; intended licence MIT OR Apache-2.0).
- The project organisation is github.com/NoWayOS. The repositories are being prepared for publication.

## The site

- [NoWayOS](https://www.nowayos.com/): The Single Purpose OS: a computer with nothing else to do. NoWayOS builds each dedicated device from only what its one job needs, on the seL4 microkernel, in Rust.
- [Platform](https://www.nowayos.com/platform): How NoWayOS builds a device from only what its job needs: sealed compartments on seL4, typed messages, a native user interface, and the hardware it runs on.
- [Security](https://www.nowayos.com/security): What NoWayOS leaves out, how it contains a fault, exactly what seL4's proofs cover, the evidence and the commands that produce it, and what stays the responsibility of whoever deploys it.
- [Projects](https://www.nowayos.com/projects): The NoWayOS projects: the Single Purpose OS itself, the Screen Compiler that turns React screens into native Rust, and the Showcase of example kiosks for the Raspberry Pi 5.

## Help

- [Help](https://www.nowayos.com/docs): Help for NoWayOS: getting started, your first seL4 system in QEMU, how a system fits together, screens from React, the Raspberry Pi 5, and the checks behind every claim.
- [Getting started](https://www.nowayos.com/docs/getting-started): Build NoWayOS's dev container and run its clickable demo, every frame checked, with no hardware and no seL4 knowledge needed.
- [Your first system in QEMU](https://www.nowayos.com/docs/first-system): Boot seL4 in QEMU with one Rust protection domain, read the three files that define a system, watch seL4 stop a part that reaches too far, and click through the user interface.
- [How a system fits together](https://www.nowayos.com/docs/how-a-system-fits-together): Protection domains, capabilities and channels; the system description and its grants file; typed messages; input; faults, the supervisor and the fail-safe state; and building your own systems beside NoWayOS.
- [Screens from React](https://www.nowayos.com/docs/screens-from-react): Design screens in React and TSX, and let the Screen Compiler turn them into native Rust for NoWayOS at build time: the supported subset, the commands, and why it refuses rather than guesses.
- [Running on a Raspberry Pi 5](https://www.nowayos.com/docs/raspberry-pi-5): What to buy, how to build and write the SD card, how to read and check the board's serial log, and how to run systems on the Pi 5 unattended or watch the user interface on its HDMI screen.
- [Checks and evidence](https://www.nowayos.com/docs/checks-and-evidence): What make ci runs and what each check shows, the ground rules every crate keeps, how to read an image's seL4 record and bill of materials, and how the gate stays fast.
- [Getting help and contributing](https://www.nowayos.com/docs/getting-help): Where to ask a question, report a bug or a vulnerability, and how to propose a change to NoWayOS.

## Reference

- [Glossary](https://www.nowayos.com/glossary): The words NoWayOS uses, each explained in a line or two: from attack surface and capability to seL4, protection domain, grants file and watchdog.
- [Questions](https://www.nowayos.com/faq): Straight answers about NoWayOS: what it is, why not lock down Linux or Windows instead, what seL4's proofs cover, whether it is ready, open source, and what it runs.

## Optional

- [Everything on this site, as one text](https://www.nowayos.com/llms-full.txt): every page's text, for reading in one go
- [The NoWayOS organisation on GitHub](https://github.com/NoWayOS): the repositories
- Terms defined on the glossary: Attack surface, Attestation, Bounded proof, Capability, Channel, Cold start, Copy, then check, CycloneDX, Debug Probe, Dev container, Double-fetch, embedded-graphics, Expect file, Fail-safe state, Fault, Formal verification, Fuzzing, Glyph atlas, Grants file, i.MX8, Isolation test, Kani, Memory-safety bug, Microkernel, Microkit, Miri, Mixed-criticality (MCS) kernel, Monotonic time, Protection domain (PD), QEMU, Raspberry Pi 5, Rust, rust-sel4, rustls, SBOM, Screen Compiler, sDDF, Secure boot, Secure by configuration, Secure by construction, seL4, sel4-config.txt, Single Purpose OS, smoltcp, Supervisor, System description, Trusted computing base (TCB), Typed message, unsafe, Wall-clock time, Watchdog