enricobuehler
f3ff5f648a
A full Plasma login starts several pieces our bare headless session was missing, which
surfaced as three separate failures while streaming the KDE desktop:
- Steam (and other X11 apps) failed "can't open display": Xwayland runs, but KWin only
sets DISPLAY for its own children — apps launched via the plasma menu / D-Bus activation
never saw it. Detect the Xwayland display after KWin is ready and export it into the
systemd/D-Bus activation environment.
- Discover / PackageKit couldn't install apps: polkitd (the policy engine) was running but
no authentication *agent* (the prompt) was — so privileged installs got no authorization.
Start polkit-kde-authentication-agent-1 (forcing the Qt Wayland platform, or it exits).
- The streamed desktop showed app windows but no wallpaper/panels: plasmashell had crashed
and the old unsupervised `plasmashell &` never brought it back. Supervise it — restart for
as long as KWin lives, so the desktop shell self-heals.
Validated live on this box: DISPLAY=:0 now in the --user environment (xdpyinfo on :0 works),
the polkit agent registers ("Listener online"), and plasmashell stays up under the supervisor.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
punktfunk
A ground-up low-latency desktop streaming stack, built Linux-first, with a shared Rust protocol core and native clients per platform.
punktfunk is a placeholder codename. The bet: ship a Linux virtual-display streaming
host that speaks the existing Moonlight protocol (every Moonlight/Artemis client works
day one), then break the ~1 Gbps FEC wall with a GF(2¹⁶) Leopard-RS transport as a
negotiated extension. See docs/implementation-plan.md.
Status
| Milestone | State |
|---|---|
M1 — punktfunk-core + C ABI |
✅ done & tested (FEC, packetization, crypto, session, punktfunk_core.h) |
M0 — pipeline spike (wlroots→PipeWire→NVENC→file→punktfunk-core) |
✅ done & verified on NVIDIA (RTX 5070 Ti / driver 595) |
| M2 — P1 host → stock Moonlight | 🟡 capture+encode landed in M0; pairing/RTSP/vdisplay pending |
| M3 — measurement harness | 🟡 tools/loss-harness runs; latency-probe scaffolded |
| M4 — P2 transport + Rust client | 🟡 GF(2¹⁶) core done; punktfunk-client-rs scaffolded |
| M5 — Apple client | 🟡 macOS first light: HEVC on glass + input over punktfunk/1 (clients/apple) |
punktfunk-core is complete and verified: it builds and its full test suite (FEC recovery,
loopback round-trip under loss, property tests, and a C ABI harness) passes on
macOS/aarch64. M0 is done: punktfunk-host captures a headless wlroots output via the
ScreenCast portal + PipeWire, encodes it with NVENC, writes a playable H.265 file, and
round-trips every access unit through a punktfunk_core host→client session (see
docs/linux-setup.md). M2 is in flight: the GameStream control plane (gamestream/) and
the management REST API (mgmt.rs, OpenAPI spec in docs/api/) are implemented; the
remaining Linux host backends (KWin/Mutter virtual displays, libei input) are
#[cfg(target_os = "linux")] seams — defined and compiling, implementations pending.
Layout
crates/
punktfunk-core/ protocol · FEC · pacing · crypto — the C ABI (lib + cdylib + staticlib)
punktfunk-host/ Linux host: vdisplay · capture · encode · inject · gamestream · mgmt
punktfunk-client-rs/ reference client (M4): VAAPI decode + wgpu present
clients/{apple,android}/ native client scaffolds (import punktfunk_core.h)
include/punktfunk_core.h cbindgen-generated C header (checked in)
tools/{latency-probe,loss-harness}/ measurement (plan §10)
docs/implementation-plan.md
Build & test
cargo build --workspace # green on Linux and macOS
cargo test --workspace # unit + loopback + proptest + C ABI harness
cargo clippy --workspace --all-targets
cargo run -p loss-harness # FEC loss-resilience sweep (no network needed)
bash crates/punktfunk-core/tests/c/run.sh # standalone C-ABI link+round-trip proof
The C header regenerates from crates/punktfunk-core/src/abi.rs on every build (cbindgen via
build.rs) into include/punktfunk_core.h.
Design invariants
- One core, linked everywhere. Protocol/FEC/crypto/pacing live in
punktfunk-coreexactly once, exposed over a stable, versioned C ABI (punktfunk_abi_version(),PunktfunkConfigcarries its ownstruct_size). - No async on the hot path. The per-frame pipeline uses native threads only;
tokio/quinnare gated behind the off-by-defaultquicfeature (control plane only). - FEC is the wall-breaker. GF(2⁸) (≤255 shards/block) for Moonlight compat; GF(2¹⁶) (≤65535 shards/block, SIMD, O(n log n)) to push past ~1 Gbps.
License
MIT OR Apache-2.0.