a87fbebc0a
`punktfunk-client --check-update` fetches the same Ed25519-signed per-channel manifest the host trusts, works out how this client was installed, and reports what — if anything — can be done about a newer build. `--apply-update` does the part it owns. `--version` prints the CI-stamped build string, which is both what the comparison needs and what a packaging gate can run the binary for. The engine lives here rather than in the Decky plugin for two reasons: verifying a signature needs crypto that Decky's embedded Python does not have, and the plugin is not the only surface that wants the answer. Every UI becomes a caller, exactly as it already is for --pair, --library and --list-hosts. What is possible depends on the install, and the module refuses to pretend otherwise. A flatpak is a per-user install its launcher can update. A .deb/.rpm/ pacman client goes through the packaged root helper — a fixed, parameterless systemd oneshot polkit authorises for members of the punktfunk-update group, so the request carries nothing an attacker could influence and the payload comes from the distro's own signed repositories. A sysext, a nix profile or a source build gets the command and nothing else: the signed sysext feed carries the HOST image, so a client sysext has no feed to update from, and a button that can only fail is worse than one honest line. A failed check reports the failure. "Could not tell" rendering as "up to date" is the one answer that must never happen. The box's capabilities are probed once into a `Caps` struct so the routing rules are a pure function of (install kind, caps) — all seven of them are tested without a box, including that the kill switch beats every kind and that pacman needs its own root-owned full-sysupgrade opt-in on top of the group. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
punktfunk — Linux client
The native Linux app for streaming a punktfunk host to your desktop, laptop, or Steam Deck.
It's a clean relm4/GTK4/libadwaita shell that finds hosts on your network, pairs with a PIN,
and manages your settings and library — the stream itself runs in the sibling
punktfunk-session Vulkan binary (clients/session), which the shell
spawns, putting the picture on glass at your display's own resolution and refresh rate.
Built in Rust end to end (no C ABI): the shell shares its plumbing with the session binary through
crates/pf-client-core, which links the punktfunk-core protocol crate and speaks the fast
punktfunk/1 protocol — QUIC control plane, GF(2¹⁶) FEC + AES-GCM data plane.
Features
- Zero-copy hardware decode — the session presenter decodes via Vulkan Video on every GPU vendor (including NVIDIA), falling back to FFmpeg VAAPI → DRM-PRIME dmabuf and then software when Vulkan Video is unavailable.
- Your display's native mode — the host builds a virtual output at exactly your WxH@Hz; no scaling, no letterboxing. Steady 60 fps at 1080p60, ~6 ms capture→decoded on the LAN.
- Audio both ways — PipeWire playback with a jitter ring, plus mic uplink to the host.
- Full controller support — SDL3 gamepads with rumble and DualSense fidelity (lightbar, player LEDs, touchpad, motion, adaptive-trigger replay). Click-to-capture keyboard and mouse, with a release chord (Ctrl+Alt+Shift+Q) and focus-loss release.
- Find hosts automatically — mDNS discovery lists hosts on your LAN; saved hosts persist. First connect does a one-time SPAKE2 PIN pairing (or TOFU on trusted LANs), then reconnects on a pinned identity.
- Per-host speed test to pick a bitrate, plus compositor and mode preferences in Settings.
- Game library browser (experimental, off by default) — "Browse library…" on a saved host shows its games (Steam + custom) as a poster grid; click one to launch it in the session. Fetched from the host's management API over mTLS — paired devices are authorized by their certificate, no extra host setup.
- Gamepad library launcher (
--browse host) — a console-style, controller-driven library view of a paired host's games, rendered by the session binary's Skia console UI: A plays the focused title, B quits, L1/R1 jump. Built for the Steam Deck plugin's "Open library" launch; session end returns to the launcher. Arrow keys/Enter/Esc drive it too (no pad needed).
Get it
Most people should install a package rather than build from source:
| Distro | Install |
|---|---|
| Flatpak (any distro, Steam Deck) | io.unom.Punktfunk — see packaging/flatpak |
| Ubuntu / Debian (apt) | sudo apt install punktfunk-client (after adding the repo) |
| Fedora / Bazzite (rpm) | rpm-ostree install punktfunk-client |
| Arch (PKGBUILD) | see packaging/arch |
Per-device install steps and pairing walkthrough: docs.punktfunk.unom.io/docs/install-client.
Build & run from source
Requires GTK ≥ 4.16, libadwaita ≥ 1.5, FFmpeg 7 or 8 (with VAAPI for hardware decode), PipeWire, and SDL3 (with hidapi) development packages.
# from the repo root
cargo run -p punktfunk-client-linux # launch the app
cargo run -p punktfunk-client-linux -- --connect HOST[:PORT] # skip the host list and connect
cargo run -p punktfunk-client-linux -- --browse HOST # the gamepad library launcher
The binary is named punktfunk-client — the relm4/libadwaita desktop shell (hosts,
pairing/trust, settings, the desktop library page). Every stream and the console game
library run in the sibling punktfunk-session Vulkan binary; the shell spawns it
for connects, and --connect/--browse on the shell exec it directly (so the Decky
wrapper keeps working unchanged). Headless flags stay in the shell:
--pair <PIN> --connect host[:port] (pairing ceremony), --wake host[:port], and
--library host[:mgmt_port] (print a host's game library).
Layout
src/
main.rs · app.rs entry point, relm4 AppModel (window, trust gate, session child
lifecycle, typed messages), primary menu, CSS
cli.rs headless paths (--pair/--wake/--library), the --connect/--browse
exec handoff to punktfunk-session, screenshot scenes
ui_hosts.rs hosts page component (FactoryVecDeque cards, saved + discovered
grids, add-host dialog, banner)
ui_library.rs game-library poster grid (per-host, launches titles)
ui_trust.rs TOFU / PIN-pairing / request-access dialogs
ui_settings.rs resolution · refresh · decoder · bitrate · compositor · mic
spawn.rs the session-child plumbing (stdout contract → AppMsg)
tools/screenshots.sh store screenshot capture (app self-capture; Xvfb fallback)
The UI-agnostic plumbing — session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads +
keymap, trust store, mDNS discovery, library client, Wake-on-LAN — lives in
crates/pf-client-core, shared with the Vulkan session binary.
Related
- Documentation — quick start, pairing, troubleshooting
- Steam Deck plugin — launches this client fullscreen in Gaming Mode
- Project README — the host, the other clients, and how it all fits together