60-punktfunk.rules chgrp's the usbip vhci attach/detach nodes to a dedicated
`punktfunk` group (security-review 2026-08-05 M-4: writing `attach` materialises
an arbitrary emulated USB device, so it must not ride on `input`). Four of the
six install paths shipped that rule in 0.25.0 without ever creating the group.
chgrp then failed, the nodes stayed root:root 0644, and the virtual Steam Deck
pad silently never attached — while `usermod -aG punktfunk` failed outright with
"group 'punktfunk' does not exist".
Affected and fixed:
* arch — post_upgrade() called only _ensure_update_group, so every box that
reached 0.25.0 by `pacman -Syu` missed it; post_install was correct.
* nix — no users.groups.punktfunk at all, though host.users' own description
already promised the usbip/vhci pad. Declares it now and adds
host.users to both groups.
* bazzite sysext — a group is host state and cannot ride an image, and the
deb/rpm scriptlets that would create it never run there.
* steamdeck install.sh/update.sh — handled `input` only. Both now create the
group and join it: running that script IS the statement "make my
Deck a host with native pad passthrough".
deb and rpm were correct throughout (one postinst/%post for install + upgrade).
Also on the Deck path: web.env secret hygiene. install.sh's `chmod 600` sat
inside the create-only branch despite a comment calling it "the idempotent belt
for a pre-existing file", and update.sh never touched the config dir at all — so
an install set up once and only updated since kept web.env world-readable
(0644) with the console password and session secret in it. Both scripts now
harden ~/.config/punktfunk to 0700 and web.env to 0600 on every run, and say so
loudly, because a chmod does not un-leak an already-readable secret: the
password still needs rotating.
Both group blocks are `if ensure_group ...` rather than `ensure_group || true`:
a failed groupadd must not fall through to a usermod against a nonexistent
group, which under `set -e` aborted install.sh after the long build and
update.sh before the service restart (verified: exit 6, no restart).
Docs: the group is now documented where people actually look — the per-distro
guides, install.md, steamos-host.md, a new troubleshooting entry for "pad
arrives as an Xbox 360 controller", and the uninstall pages. The 0.25.0 notes
gain the "group does not exist" caveat and turn the password bullet from
"consider rotating" into a real instruction, and CHANGELOG records the known
issue against the breaking change that introduced it.
Verified: bash -n on all four scripts; the arch scriptlet's post_upgrade driven
in a container (creates the group, idempotent on re-run); the ensure_group
helper and both membership branches, including a control that reproduces the
original bug (chgrp to a missing group leaves the node root:root 0644); the
find -perm /0077 probe across 0644/0640/0604/0600/0400 on GNU findutils;
`nix flake check --no-build` (the exact CI gate) and a NixOS eval showing
alice.extraGroups == ["input","punktfunk"]; docs-site build + typecheck.
11 KiB
title, description
| title | description |
|---|---|
| Arch Linux | Install a Punktfunk host on Arch (and Arch-derived distros) from the signed pacman binary repo. |
Set up a Punktfunk host on Arch Linux (or an Arch-derived distro like CachyOS/EndeavourOS). The
host installs from a signed pacman binary repo, so it updates with pacman -Syu like the rest
of your system — no building required. Host encode is NVENC on NVIDIA; on AMD/Intel HEVC
and AV1 go through Vulkan Video, with VAAPI for H.264 and as the fallback
(PUNKTFUNK_ENCODER=auto picks per GPU).
New here? Read Security & Safe Use first — a streaming host is remote control of the machine, so keep it on a trusted LAN or VPN and require pairing.
Prefer to build it yourself? A split
PKGBUILD(host + client + optional web console) is in the repo atpackaging/arch/— see the appendix. The binary repo below is the supported path.
1. GPU prerequisites
- NVIDIA:
sudo pacman -S --needed nvidia-utils(provides NVENC + the EGL/CUDA zero-copy path). Arch's stockffmpegalready has NVENC built in — no RPM-Fusion-style swap like Fedora needs. - AMD / Intel: the Mesa stack. HEVC/AV1 encode goes through Vulkan Video by default, so
install the Vulkan driver —
vulkan-radeon(AMD) orvulkan-intel(Intel) — alongside the VAAPI drivers (libva-mesa-driverfor AMD,intel-media-driverfor Intel), which carry H.264 and the fallback path. Both are usually already installed on a desktop.
2. Add the signed repo
The registry signs its database and every package, so first trust its key once (after this, packages install signature-verified):
# Trust the registry signing key.
curl -fsS https://git.unom.io/api/packages/unom/arch/repository.key \
| sudo pacman-key --add -
sudo pacman-key --lsign-key E0CA04465C99C936E0B0C6510A317015A34DDD69
# Add the repo (append to /etc/pacman.conf). No SigLevel line needed — pacman's default
# verifies signed packages against the key you just trusted. (printf, not a heredoc, so this
# works in fish too — CachyOS's default shell has no `<<EOF` support.)
printf '\n[punktfunk]\nServer = https://git.unom.io/api/packages/unom/arch/$repo/$arch\n' \
| sudo tee -a /etc/pacman.conf >/dev/null
Stable vs canary.
[punktfunk]is the stable channel — it moves only when avX.Y.Zrelease is cut. For the latestmainbuild, use[punktfunk-canary]instead (sameServerline, just the repo name). Enable exactly one. See Release Channels.
3. Install the host
sudo pacman -Syu punktfunk-host # the streaming host
sudo pacman -Syu punktfunk-web # optional: the browser management console (pairing + status)
sudo pacman -Syu punktfunk-gamescope # optional: HDR (10-bit BT.2020 PQ) off gamescope sessions
sudo pacman -Syu punktfunk-scripting # optional: the plugin/script runner (see below)
sudo usermod -aG input "$USER" # /dev/uinput access for virtual gamepads (re-login to apply)
Only if you want the virtual Steam Deck controller (paddles, trackpads, gyro — it reaches games
as a real USB pad, which is why Steam Input adopts it), also join punktfunk:
sudo usermod -aG punktfunk "$USER" # usbip/vhci access (re-login to apply)
That is a second group on purpose. It grants write access to the usbip attach file, which
materialises an arbitrary emulated USB device — so it stays off the input group everyone is
routinely told to join. Join it only on a machine you trust. Without it, everything else still
works and the pad simply arrives as an ordinary Xbox 360 controller.
Each install is a full -Syu, on purpose: our packages are built against current Arch
sonames, and pacman -Sy <pkg> would drop one onto a system whose other packages are still old —
the classic partial upgrade that breaks Arch boxes. To take several in one go, name them on a
single line: sudo pacman -Syu punktfunk-host punktfunk-web punktfunk-gamescope.
punktfunk-scripting is the runner behind Plugins; it isn't started for you —
systemctl --user enable --now punktfunk-scripting when you want it. punktfunk-client (the native
GTK4 Linux client) is in the same repo if this box is also a client. The host package ships the
systemd user units, the udev rule, the UDP socket-buffer sysctl tuning, and example configs.
Updates later are a normal sudo pacman -Syu, then systemctl --user restart punktfunk-host so the
running host picks up the new binary. A -Syu moves every Punktfunk package you installed, so
restart punktfunk-web the same way if you run the console. The web console can run the update for
you — see Updating the Host; on Arch that button additionally needs
PACMAN_FULL_SYSUPGRADE=1 in /etc/punktfunk/update.conf, because the only pacman update we will
run is a full one.
4. Configure and run
The host runs as a systemd --user service — it needs your session's PipeWire and D-Bus. Copy a
starting config:
mkdir -p ~/.config/punktfunk
cp /usr/share/punktfunk/host.env.example ~/.config/punktfunk/host.env
How the host creates its virtual display and injects input depends on your desktop, not your distro —
edit host.env for the desktop you run, following its page for the exact settings and any quirks:
Then enable the service and turn on linger so it starts at boot without a login:
systemctl --user daemon-reload
systemctl --user enable --now punktfunk-host
sudo loginctl enable-linger "$USER"
Check it came up:
systemctl --user status punktfunk-host # active
journalctl --user -u punktfunk-host -f # watch a client connect
Enable the browser console, find your login password, and arm PIN pairing from The Web Console. For a headless KWin appliance that streams at boot with no graphical login, see KDE → Headless session. Full reference: Configuration · Running as a Service.
5. Open the firewall (if you have one)
Stock Arch ships no firewall — every port is already open, so you can skip this. But CachyOS
enables ufw by default (firewalld is not installed), and some other spins (e.g. EndeavourOS)
enable firewalld — an Arch package never opens ports for you, so on those the host is
unreachable until you allow it.
The punktfunk-host package installs openers for both, so it's a one-liner whichever you run.
The unit you enabled in step 4 runs serve --gamestream — the package installs it as it ships and
only rewrites the binary path — so that host serves both the native punktfunk/1 plane and
stock Moonlight clients, and needs both openers:
# ufw — CachyOS (and Ubuntu, once you enable ufw):
sudo ufw allow punktfunk-native
sudo ufw allow punktfunk-gamestream
# firewalld — Fedora-like spins (EndeavourOS, …):
sudo firewall-cmd --reload # load the installed definitions
sudo firewall-cmd --permanent --add-service=punktfunk-native
sudo firewall-cmd --permanent --add-service=punktfunk-gamestream
sudo firewall-cmd --reload
Switched the host to native-only — dropped --gamestream with a
systemctl --user edit punktfunk-host drop-in, or you run punktfunk-host serve by hand? Then open
punktfunk-native alone and leave punktfunk-gamestream closed. systemctl --user cat punktfunk-host shows which one yours is.
punktfunk-native opens the QUIC control port (UDP 9777), mDNS discovery and the mgmt/library API
(TCP 47990); punktfunk-gamestream opens the fixed Moonlight ports — TCP 47984, 47989 and 48010,
UDP 47998–48000 — plus the same mDNS.
The media data plane uses an ephemeral UDP port that the client opens with a hole-punch — the
host streams back out through the path the client opened, so there's nothing fixed to open as
long as the firewall allows outbound UDP (the default for both ufw and firewalld).
Enabled the web console (punktfunk-web, above) and want to reach it from your phone or another
machine? It's not opened by the streaming rules — open its port too, the same one-liner way:
sudo ufw allow punktfunk-web # ufw
sudo firewall-cmd --permanent --add-service=punktfunk-web && sudo firewall-cmd --reload # firewalld
That opens TCP 47992 (HTTPS, login-gated). The mgmt API (47990) is opened for paired clients by the
punktfunk-native profile (game-library browsing over mTLS); off-loopback it serves only read-only
status/library, and every admin action stays loopback-only. Full port lists (nftables, explicit ports) are in
packaging/arch/README.md.
6. Connect a client
From any client, --discover finds the host on the LAN. On first connect, complete
the PIN pairing: arm it from The Web Console, which displays a
4-digit PIN to type into the client. (Pairing is required by default; pass serve --open only if
you deliberately want to disable it.) See Clients for per-platform setup.
Next steps
- Keep it current — Updating the Host.
- Remove it again — Uninstalling.
- Something not working? — Troubleshooting.
Appendix — build from source (PKGBUILD)
To build instead of using the binary repo, use the split PKGBUILD in packaging/arch/ (produces
punktfunk-host + punktfunk-client; set PF_WITH_WEB=1 to also build punktfunk-web and
PF_WITH_SCRIPTING=1 to also build punktfunk-scripting — both need bun):
git clone https://git.unom.io/unom/punktfunk.git && cd punktfunk/packaging/arch
# Build the working tree (no git fetch):
PF_SRCDIR="$(git rev-parse --show-toplevel)" makepkg -f --holdver
sudo pacman -U punktfunk-host-*.pkg.tar.zst
NVENC/EGL come from the NVIDIA driver (nvidia-utils); on a GPU-less builder, symlink the CUDA
stub into the link path first (the PKGBUILD header documents this). Full details, the
Fedora→Arch dependency map, and the systemd-sysext mechanism are in
packaging/arch/README.md.
(For a SteamOS host, use the on-device installer instead — it builds
the host and the HDR gamescope against the running OS.)