enricobuehler
0bc60ebc44
On a Bazzite host that autologins into gaming mode on a physical display (the F44 default: gamescope-session-plus@ogui-steam on the TV), Steam — single-instance — is held by that session, which renders to the TV's native mode. The host-managed session then can't start its own Steam, so it captured the TV's 4K output instead of the client's mode (stretched). On F43 the box wasn't in gaming mode, so the host's Steam was the only one. Fix: on connect, the host-managed gamescope path stops any running autologin `gamescope-session-plus@*` unit (frees Steam) before launching its own session at the client's mode; on client disconnect (`restore_tv_session`, called from serve_session teardown) it stops our session and restarts the autologin one, so the TV returns to gaming mode by default when no one is streaming. Stopping the `--user` unit sticks (Relogin only fires on the full logind session ending — verified live), so no sddm config change is needed. Cost: a Steam cold-start per connect, given single-instance. No-op on non-Bazzite / headless boxes (nothing to stop → nothing to restore). 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 & hardened (FEC, packetization, AES-GCM, session, adversarial-review fixes, punktfunk_core.h) |
| M2 — GameStream host → stock Moonlight | ✅ live end-to-end: pairing, RTSP, audio, per-client virtual output at native res, GPU zero-copy NVENC, gamepads |
M3 — punktfunk/1 native protocol |
✅ validated live: QUIC control + GF(2¹⁶) FEC/AES data plane, SPAKE2 PIN pairing, mid-stream mode renegotiation |
| M4 — client decode + present (Apple) | 🟡 macOS first light: AnnexB→VideoToolbox HEVC on glass + input/pairing over punktfunk/1 (clients/apple); iOS + presenter next |
| Web console + management API | ✅ TanStack web console (web/) over the OpenAPI mgmt API: host status, paired devices, on-demand native pairing (arm → show PIN) |
The GameStream host works with a stock Moonlight client — validated live on NVIDIA
(RTX 5070 Ti & RTX 4090, driver 595): trust-on-first-use pairing that persists, an app
catalog, RTSP/ENet/audio, and video at the client's exact resolution and refresh via a
per-session virtual output (KWin, gamescope, Mutter, Sway backends), encoded with GPU
zero-copy (dmabuf → CUDA/Vulkan → NVENC) at up to 5120×1440@240. The native
punktfunk/1 protocol adds a QUIC control plane and a GF(2¹⁶) Leopard-FEC + AES-GCM data
plane (p50 ~0.8 ms capture→reassembled at 720p120), with a SPAKE2 PIN pairing ceremony. Both
run from one process (serve --native), managed through a REST API + web console. Builds
against FFmpeg 7 or 8; deployed live on Bazzite. Full status: CLAUDE.md;
roadmap, setup guides & progress: the docs site (docs-site/ — Fumadocs;
bun run dev), with the canonical roadmap and
status there. Design notes stay in docs/.
Layout
crates/
punktfunk-core/ protocol · FEC · pacing · crypto · quic — the C ABI (lib + cdylib + staticlib)
punktfunk-host/ Linux host: vdisplay · capture · encode · inject · gamestream · m3 · mgmt · native_pairing
punktfunk-client-rs/ punktfunk/1 reference client (M3 headless; M4 adds decode+present)
clients/{apple,android}/ native client scaffolds (import punktfunk_core.h); apple = macOS first light
web/ TanStack web console (host status · paired devices · pairing) over the mgmt API
packaging/ Fedora/Bazzite RPM · bootc image · COPR (see packaging/bazzite/README.md)
include/punktfunk_core.h cbindgen-generated C header (checked in)
tools/{latency-probe,loss-harness}/ measurement (plan §10)
docs/{implementation-plan,roadmap,windows-host,dualsense-haptics}.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.