A QNX-inspired operating system with selectable kernels

A QNX-inspired operating system with selectable kernels. News: QSOE 0.1 is out — the first public release of the unified two-kernel system (June 2026). Read the announcement → QSOE ships in two variants that share one userspace and one build system. QSOE/N runs on Skimmer, a microkernel written from scratch for this project (SMP by design); QSOE/L runs on seL4 as its kernel. Both variants, when compiled, offer the kernel and initrd files directly usable in e.g. U-Boot loader. The userspace is 100% identical across both variants; the only parts produced per-kernel are taskman, the task manager, and libc.so — the C library, which is around 85% shared at the source level and diverges only at the thin layer where it meets the kernel. The design follows the QNX Neutrino tradition: a small kernel with everything else in userspace, synchronous message-passing IPC, and the resource-manager model for services. QSOE targets 64-bit RISC-V (RV64, Sv39) on the SiFive HiFive Unmatched (FU740), with QEMU used for day-to-day development. Both QSOE variants now boot on real hardware. Released under Apache-2.0. QSOE can be built from source or installed from pre-built binaries. Ready-made images for each release are published at github.com/qsoe-dev/dl (current release: 0.1). The files are: In short: to run it in QEMU, grab nvme.img.gz (plus virtio.img.gz for QSOE/L) and see Running under QEMU. To put it on real hardware, you need mrbml-riscv64.efi plus the kernels — QSOE/N uses skimmer.bin + modpkg.cpio, QSOE/L uses one of the qsoe-l-*.elf images — and see Installation. The quickest way to see QSOE run — no hardware, no -kernel juggling. The nvme.img download is a self-booting UEFI disk: QEMU's firmware runs mr-bml from it, and mr-bml's menu starts either variant straight off the disk. # unpack the image(s) — add virtio.img.gz only if you want QSOE/L gunzip nvme.img.gz virtio.img.gz # point the launcher at them and pick a variant from its menu NVME_IMG=./nvme.img VIRTIO_IMG=./virtio.img ./run-nvme.sh Pass n or l to skip the menu (./run-nvme.sh n). The script selects the matching QEMU machine automatically — QSOE/N on the AIA machine with an NVMe root, QSOE/L on the PLIC machine with the virtio root disk. The mr-bml menu and the system console both appear on your terminal; choose a variant and it boots to a login: prompt. Log in as root with password QSOE. Real hardware, real disk. QSOE 0.1 boots on the SiFive HiFive Unmatched (FU740); the SpaceMiT K3 is a future target. This assumes a board already running Linux — you'll be placing files on its existing EFI and boot partitions, so familiarity with the board's firmware is expected. The boot model is simple: mr-bml lives in the EFI System Partition; it reads its menu and the kernels from an ext2/3/4 partition; the chosen variant then mounts its own root from a fs-qrv partition. # /boot/mr-bml/mr-bml.cfg — adjust the mainfs= partition to your disk menuentry 'QSOE/N (Skimmer)' { kernel /boot/qsoe/skimmer.bin mainfs=/dev/nvme0n1p8 modpkg /boot/qsoe/modpkg.cpio } menuentry 'QSOE/L (seL4)' { kernel /boot/qsoe/qsoe-l-sifive.elf mainfs=/dev/nvme0n1p8 } The mainfs= device names the partition holding the QSOE root filesystem (fs-qrv) — set it to whichever partition you've devoted to QSOE on your board. On real hardware there is no QEMU virtio split: both variants drive the NVMe disk directly. QSOE is built with a riscv64-linux-gnu- cross toolchain (rv64gc) and a stock make; QEMU is handy for testing. The umbrella repository orchestrates the build and pulls in the component repositories that match its release tag. git clone https://gitlab.com/qsoe/os cd os make prepare # fetch the components for this tag (see component.list) make # build both variants: QSOE/N, then QSOE/L make dist # optional: the QEMU disk images (nvme.img.gz, virtio.img.gz) QSOE/L additionally shallow-clones the seL4 kernel during make prepare. The build produces exactly the files on the Downloads list. The whole tree is Apache-2.0; the source lives under gitlab.com/qsoe. The QSOE manuals, published as PDF alongside the releases: It is often said that the Linux kernel has no roadmap. QSOE does — the ten releases that carry it from today's 0.1 to the unified 1.0 are mapped out. A working plan, not a contract: milestones may shift as the work reveals what's really next. Consulting and development in low-level and systems software. Engagements range from focused bring-up work to longer-term architecture and implementation. Get in touch to discuss scope. QSOE Systems is the independent practice of Yuri Zaporozhets, a systems software developer with 25+ years of experience building low-level software — kernels, operating systems, runtimes, and the hardware bring-up underneath them.

A QNX-inspired operating system with selectable kernels

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