How NoriOS works

Its own kernel, two kinds of programs

NoriOS is not built on Linux or Windows. It has a kernel of its own, and that kernel speaks two languages. A program started from a Linux program file gets Linux's system calls; one started from a Windows .exe gets Windows's. Both run directly on the processor, with nothing emulated or translated in between, and because both are served by the same kernel, they share the same files, pipes and network connections.

The Windows side is NoriOS's own work: the kernel's objects, handles and waits, and the system libraries Windows programs load (ntdll, kernel32, user32 and the rest), written from Microsoft's documentation and tested against real programs. It contains no Wine code.

Software from Linux distributions

Linux programs come from Linux distributions, used as sources of software rather than as the system. Each one stays whole in a root of its own and is maintained by its own package manager, so programs built for Alpine and programs built for Arch run side by side, each seeing the files it expects.

Drivers as programs

Where it can, NoriOS keeps drivers outside the kernel. The display is served by a program of its own, and NVIDIA's open GPU driver runs as an ordinary program too. If one crashes, it takes the display down with it, not the system, and it can be started again.

Updates without a restart

NoriOS can replace its entire kernel while your programs keep running: their memory, open files, windows, network connections and timers are all where they were when the new kernel takes over. Programs notice a pause of a few milliseconds.

This is possible because the compiler that builds NoriOS knows the shape of everything the kernel keeps, and how it changed between two versions, so it can carry each piece across. A new kernel starts on probation with a watchdog behind it; if anything goes wrong, the old one takes back over.

Every file's story

When a file is created, the kernel records who made it: which program, and where its contents came from, a download's address included. Files shows this as the file's origin, and as a timeline of what you did.

Written in Nori

The kernel, its drivers, the desktop, its apps and the Windows libraries are all written in Nori, a programming language made alongside NoriOS. It is memory-safe without a garbage collector, and its compiler builds the whole system on its own, without a C toolchain for the kernel.