SynapseOS

What is SynapseOS?

Most “AI operating systems” are a chat window on a normal desktop. SynapseOS starts one layer down. A local inference daemon called synapd owns the model and serves every other component over the SYN socket protocol, so the AI is a system service in the same sense that systemd-resolved is — something the rest of the OS can depend on rather than an app you open.

The desktop is synui, a wlroots Wayland compositor written for this system rather than adapted to it — one that knows the AI daemon exists and holds a live subscription to the security monitor’s verdict feed.

• Local inference, no accounts

  The installer downloads one model — Mistral 7B Instruct (Q4_K_M, ~4.1 GB) is the recommendation, and you can decline — and runs it through llama.cpp. Nothing to configure afterwards, and nothing leaves the machine.

• An assistant with the run of the desktop

  vibe is a chat window and a terminal command in one — it opens folders and panels, changes settings and applies them live, reads and edits files, and runs commands you confirm. Plain requests never reach a model at all. It uses the resident model by default, or Claude or OpenAI with a key.

• A shell that takes English

  synsh is a normal POSIX-ish shell until you stop typing commands. Describe the outcome instead and it resolves the intent against the local model — then shows you what it is about to run.

• A compositor of its own

  synui runs on wlroots 0.20 and renders through scenefx 0.5: tiling and monocle layouts, XWayland, layer-shell, glass, blur, shadows, and an optional CRT post-process pass. Workspaces are shared across monitors or one set per monitor, switching flat or as a turning cube, and a display that can take HDR10 can be driven in it.

• Security that enforces in-kernel

  synguard classifies syscall events, scores threats and publishes verdicts on a feed the desktop subscribes to. Since 0.2.4 it can also deny in-kernel through a BPF-LSM gate, behind warmup, heartbeat and deny-budget guards.

• Telemetry from a real kernel module

  synapse_kmod is a DKMS module exporting syscall telemetry and AI scheduling hints through /sys/kernel/synapse/ — syscall_log, ai_hints, stats, status, config, version.

• A terminal that links no GL

  syntty is the default terminal: wl_shm, xdg-shell, xkbcommon and libc, cells to pixels on the CPU. 359 KB, a window in 5.8 ms, tabs, images, and OSC 133 prompt marks that synsh emits at the other end. A live image cannot count on a GL context.

• Applications of its own

  A file manager (synfiles), a package manager (synpkg), settings (syn-settings), an editor (syn-edit), a disk utility (syn-disks), a calendar (syn-cal), a media player (syn-play), a locked folder (syn-vault) and a disk cleaner (syn-clean) — each written for this system, and each a window and a command line over one binary rather than two programs that disagree.

• Fourteen languages, everywhere

  English, German, French, Spanish, Portuguese, Italian, Dutch, Polish, Russian, Japanese, Chinese, Korean, Hindi and Arabic — in the installer and in every application on the system, not the installer alone. The compositor shapes its own text through HarfBuzz and FriBidi, so Arabic joins and reads right to left. The language is the first question the image asks, from the boot menu, and nothing asks again.

• A ten-foot interface

  Big screen mode (Super+F10, or the pad’s Guide button) puts the Steam library, Big Picture, a browser, music, and any Plex or Jellyfin server on the network on a television — drivable from a controller, including as a mouse.

• An installer that respects your disk

  syn-install offers a whole-disk install with optional LUKS2 full-disk encryption, or — on UEFI, where the disk already holds another OS — a non-destructive dual-boot into existing free space, reusing the machine’s ESP. Four filesystems, three bootloaders.

How it fits together

One model, resident once, shared by everything. Components do not each load their own copy — the desktop assistant reuses the model already sitting in synapd rather than spending a second allocation of VRAM.

  User
   │
   ▼
 synsh ─── natural language / commands ──┐
   │                                     │
   ▼                                     │
 synapd  (local LLM — Mistral 7B)        │
   │  inference over SYN socket protocol │
   ├──► synguard      security verdicts ─┤
   ├──► synnet        network policy     │
   └──► synapse_kmod  kernel sysfs       │
            │                            ▼
            ▼                    synui (Wayland)
     /sys/kernel/synapse/
     syscall_log, ai_hints, stats,
     status, config, version

The desktop

synui draws its own display settings, wallpaper picker, dock, cursor picker, sound panel and control panel. The status bar and the desktop widgets are a native quickshell shell. Everything below is compositor-drawn — there is no third-party panel or settings app in the picture.

A fresh install boots into SYNAPSE Prism, and Prism has no colour of its own: it is one dark, near-neutral surface at low alpha, and the wallpaper supplies the colour through it — measured live, on every wallpaper change, and carried to the bar, the dock, the icons and, if there is anything in the machine that glows, to the RGB hardware as well. Fifteen themes ship, Prism Light among them; one slider sets how much of the desktop you see through.

The bar takes third-party widgets in Omarchy’s shell-plugin format. Their desktop is a quickshell process and so is this bar, which makes their format the only one already describing “a QML widget you can drop into a quickshell bar” — so a widget written once loads on either. synui-plugins browse lists what you can install, and there is a terminal browser and a window for it too.

CRT filter CRT filter · amber

Some of what the keyboard reaches

The full table — sixty-odd bindings — is in the README, and Super+C generates it live from the running bind table.

A look around

Every window below is part of SynapseOS. The file manager, the package manager, the settings, the disk utility, the task manager and the editor are all written for this system — there is no third-party desktop suite underneath.

Components

Each lives in its own directory in the tree with its own PKGBUILD. Twenty-two of them are also published separately, each from its own repository under github.com/velle999 — so the desktop, the terminal, the applications and the AI stack build and install on a plain Arch machine that has never seen this ISO.

Download SynapseOS

Latest release: 1.0.1 — signed and verified updates, a firewall that asks about each network, and a malware scanner that says what it found. Free, x86_64, about 4.6 GiB. The model is downloaded during installation, not carried in the image.

Download the ISO — 4.6 GiB Mirror Torrent

One file, resumable, nothing to reassemble. The mirror is the Internet Archive, which carries the same image and the torrent for it.

Check your download

A 4.6 GiB download that stops early still looks like an ISO and still writes to a stick. The checksum is what tells you it arrived whole.

Linux / macOS

curl -O https://dl.soslinux.org/SynapseOS-1.0.1-x86_64.iso.sha256
sha256sum -c SynapseOS-1.0.1-x86_64.iso.sha256   # shasum -a 256 -c on macOS

Windows

In PowerShell, in the folder you downloaded to:

(Get-FileHash -Algorithm SHA256 .\SynapseOS-1.0.1-x86_64.iso).Hash -eq `
  (((Get-Content .\SynapseOS-1.0.1-x86_64.iso.sha256) -split '\s+')[0]).ToUpper()

True means the download is intact. Get-FileHash prints uppercase hex where sha256sum writes lowercase — same bytes, hence the .ToUpper(). In Command Prompt instead: certutil -hashfile SynapseOS-1.0.1-x86_64.iso SHA256, and compare it against the .sha256 file yourself.

cat SynapseOS-1.0.1-x86_64.iso.part* > SynapseOS-1.0.1-x86_64.iso
sha256sum -c SynapseOS-1.0.1-x86_64.iso.sha256   # shasum -a 256 -c on macOS

copy /b SynapseOS-1.0.1-x86_64.iso.part00 + SynapseOS-1.0.1-x86_64.iso.part01 + SynapseOS-1.0.1-x86_64.iso.part02 SynapseOS-1.0.1-x86_64.iso
certutil -hashfile SynapseOS-1.0.1-x86_64.iso SHA256

Check who built it

The checksum above proves your download arrived whole. It does not prove where the image came from: it is served from the same place as the ISO, so anything that could alter one could alter the other. The signature is the part that answers that.

A signature is only worth your confidence that the key behind it is the right key. This one’s fingerprint is also committed in the source repository, as archiso/release-key.fingerprint — a different host, run by somebody else, than the one that served you the image. Compare all three: what gpg prints, what is on this page, and what is in the repository.

Releases from 0.2.9.5 onward carry a .asc signature. Earlier ones, including 0.2.9.4, do not — there is nothing to check on those.

Linux / macOS

curl -O https://soslinux.org/synapseos-release-key.asc
gpg --import synapseos-release-key.asc

gpg --verify SynapseOS-1.0.1-x86_64.iso.asc SynapseOS-1.0.1-x86_64.iso

A good signature prints Good signature from "SynapseOS Release Signing". Check the fingerprint it names against this one:

6548 9EF5 C20D 0BD9 4211  472B ED33 6DB7 952B 609E

gpg will also say the key is not certified with a trusted signature. That is expected and is not a failure: it means you have not told GnuPG you trust this key, only that the signature matches it. Comparing the fingerprint above is what closes that gap.

Windows

With Gpg4win installed, the same three commands work in PowerShell. Without it, the SHA256 check above is still worth doing on its own.

Write it to a USB stick

Writing a stick erases it. Everything already on it is gone.

Linux / macOS

sudo dd if=SynapseOS-1.0.1-x86_64.iso of=/dev/sdX bs=4M status=progress oflag=sync

Check /dev/sdX with lsblk first, and write to the disk (/dev/sdb), not to a partition on it (/dev/sdb1).

Windows

• Rufus — pick the ISO, press START, and choose DD Image mode when it asks. This is a hybrid image; ISO mode rebuilds boot files it has no reason to get right.
• balenaEtcher — nothing to configure.
• Ventoy — copy the .iso onto a stick that already has Ventoy on it and pick it from the boot menu. The one option here that erases nothing.

Then boot the stick from your firmware’s boot menu — usually F12, F11, Esc or Del at power-on. Secure Boot has to be off, or SynapseOS enrolled; see Secure Boot.

Or try it in a VM first

git clone https://github.com/velle999/SYNAPSE.git && cd SYNAPSE
QEMU_RAM=8G ./archiso/build_scripts/qemu-test.sh

The script auto-detects the newest ISO, uses KVM when available, boots UEFI via OVMF, and attaches a persistent 20 GB test disk.

System requirements

• CPU — x86_64. CPU inference is the default and works everywhere.
• RAM — 8 GB minimum; a resident 7B model is the reason.
• Disk — ~25 GB for an install, plus room for the model.
• Network — needed once, during installation, to fetch the model.
• GPU — optional. NVIDIA via a CUDA build, AMD and Intel via Vulkan.
• Firmware — UEFI or BIOS. Dual-boot installs need UEFI.

Frequently asked questions

Does SynapseOS send anything to the cloud?

No. The installer downloads a model once; after that the file lives on the machine and inference runs locally through llama.cpp. There are no API keys to configure and no account to create, and the AI works with the network cable out.

Is it just Arch with an app on top?

No. The inference daemon is a system service and the components query it over a socket: the shell resolves intent through it, the compositor talks to it, the security monitor uses it to classify events. The desktop, the shell, the security monitor, the network daemon and the kernel module are all written for this project.

Can I run it on a machine with no GPU?

Yes — that is the default. The ISO ships a CPU build of the inference backend so it starts on any x86_64 machine. GPU acceleration is a separate package you install afterwards if you have the hardware.

Is it free and open source?

Yes. SynapseOS-authored code is GPL-2.0-or-later, except the kernel module, which is GPL-2.0-only because the Linux kernel is. The whole tree is on GitHub.

Can I use it as my daily driver?

Yes. The author does, and at 1.0 it is ready for you to do the same. It is a rolling release, so it keeps moving after you install it, and a VM is still the quickest way to look around first.

How do updates work?

An installed system needs two commands, because they cover different halves of it: sudo pacman -Syu for Arch, and syn-update check / syn-update apply for the SynapseOS components. There is a GUI for the second one in the start menu.

Merch

Two mugs, a sticker and a lamp. They are printed and shipped by Printify, which also takes the payment — this site sells nothing and stores nothing about you. Buying one is not how the project gets funded; it exists because people asked for a mug.

• SynapseOS Logo Ceramic Mug $12.40
• Custom UV Acrylic Night Light from $13.72
• SynapseOS Purple Logo Vinyl Sticker from $4.09
• SynapseOS Glass Mug, 10 oz $26.10

There is more in the store than the four above — a t‑shirt, a hoodie, a trucker hat, kiss‑cut stickers and a pair of socks, all carrying the same mark.

Prices are copied here for convenience and can drift — the store is the one that is right. Anything with sizes shows its cheapest.