The solnix handbook
The solnix Operating System is a supported distribution of illumos built entirely with the Nix package manager and the NixOS module system — the illumos analog of NixOS (Linux) and nixbsd (FreeBSD/OpenBSD).
The solnix OS targets four CPU architectures — x86_64, aarch64,
RISC-V, and SPARC (the x86_64-solaris, aarch64-solaris,
riscv64-solaris, and sparcv9-solaris systems) — and is designed for both
server and desktop use. It is optimized for virtualized hosting on all the
major cloud platforms (AWS/EC2, Microsoft Azure, Google Cloud, and the rest),
while remaining a first-class OS on bare metal.
Describe an illumos machine declaratively in Nix; get a bootable, atomically upgradeable, rollback-capable system backed by ZFS boot environments.
Status: early / preview. The first bootable image has landed — an unstable-edition x86_64 ISO + raw disk image (v2026.08.07), preview-grade (Download). The positioning above describes the target the solnix OS is designed for, not everything that runs today. x86_64 is the primary target; aarch64, RISC-V, and SPARC are in bring-up (see CPU architecture support). Desktop is now within reach: the COSMIC desktop runs on solnix, proving the graphical stack works on illumos — Rust, Wayland, GTK4, and GPU acceleration via Mesa RADV + Vulkan (a graphical install ISO is coming soon). This handbook documents the design and the working infrastructure (binary cache, package search) as they come online. It does not over-claim: sections marked planned are not yet real.
Why
illumos-gate is fully buildable from source today, ships ZFS + zones + bhyve +
LX-branded zones, and already has a native atomic-upgrade story (beadm boot
environments). Nix’s immutable store + generation model maps cleanly onto that.
solnix marries the two.
How, in one breath
Reuse NixOS’s evaluator and module system verbatim; add an *-illumos platform
and a fine-grained pkgs.solnix.* world to a nixpkgs fork; drive services
through SMF (not systemd) via an smf.services.* module; bake /nix/store
paths into ELF RUNPATH with the Solaris link-editor (no GNU tooling); map
each Nix generation onto a ZFS boot environment. This is nixbsd’s playbook,
retargeted to illumos.
Where to go next
- New here entirely? A short history explains what solnix descends from (SunOS → Solaris → illumos → solnix) in a page.
- Coming from Linux or NixOS? For Linux (and NixOS) users is the orientation map (systemd→SMF, Docker→zones, ext4→ZFS, and so on).
- New to illumos? Start with illumos features — the ZFS / DTrace / SMF / zones / boot-environment platform solnix inherits.
- Know Nix already? See How solnix is built for how the illumos target is wired, and Learning Nix for what differs.
- Want to use what is live today? Getting started, the binary cache, and package search.