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+# TeleportFling
+
+Standalone Linux screen + audio sender for the
+[OBS Teleport protocol](https://github.com/fzwoch/obs-teleport).
+
+TeleportFling captures a Wayland screen (via `xdg-desktop-portal` + PipeWire)
+and the system's default audio, encodes the video to JPEG, packetizes both
+into the Teleport protocol, and streams them over TCP so any OBS instance
+with the `obs-teleport` plugin can discover and display the stream.
+
+## Features
+
+- **Real screen + audio capture** on Wayland (PipeWire / xdg-desktop-portal).
+- **LAN discovery** via UDP multicast, matching obs-teleport's `AnnouncePayload`.
+- **Multiple receivers** — every connected OBS streams from one sender.
+- **Headless CLI** (`teleportfling`) and **desktop GUI + system tray**
+  (`teleportfling-gui`).
+- **Config persistence** at `~/.config/teleportfling/config.json`, customisable
+  with `--config`.
+- **Daemon mode** via a per-user systemd service (see `contrib/`).
+
+## Build & run
+
+Requires a Nix dev shell (or Go 1.26+ with libjpeg-turbo and the Fyne/GLFW
+native deps for the GUI).
+
+```sh
+nix develop
+go build ./cmd/teleportfling       # headless CLI
+go build ./cmd/teleportfling-gui   # desktop GUI + tray
+```
+
+Run:
+
+```sh
+./teleportfling --name "Studio" --port 9756
+```
+
+Flags: `--name`, `--port`, `--quality`, `--fps`, `--source screen|pattern`,
+`--audio`, `--no-announce`, `--stream-index`, `--duration`, `--config`.
+
+## Network requirements
+
+TeleportFling uses two kinds of traffic:
+
+| Port  | Proto | Direction      | Purpose                          |
+|-------|-------|----------------|----------------------------------|
+| 9756  | TCP   | Sender → listen | Video + audio stream to receivers |
+| 9999  | UDP   | Sender → listen | multicast discovery (peerdiscovery) |
+
+For a **sender** to be discoverable and reachable by OBS receivers on another
+machine, **both** machines need these ports open:
+
+### NixOS
+
+```nix
+networking.firewall = {
+  enable = true;
+  allowedTCPPorts = [ 9756 ]; # TeleportFling screen/audio streaming
+  allowedUDPPorts = [ 9999 ]; # TeleportFling multicast discovery
+};
+```
+
+Apply with `sudo nixos-rebuild switch --flake .#<hostname>`. If the machines
+are on separate/isolation LANs, Tailscale works as an alternative transport
+(point OBS at the receiver's Tailscale IP:port), but the multicast
+discovery list will only show senders reachable via LAN multicast.
+
+### Other distros / firewalls
+
+Open TCP **9756** inbound and UDP **9999** inbound on the sender machine;
+receivers just need outbound access (or the same rules if a firewall restricts
+it). mDNS (UDP 5353) is only needed for zero-config name resolution, not for
+TeleportFling itself.
+
+## Daemon mode
+
+See `contrib/README.md` — `contrib/install-daemon.sh` installs a per-user
+systemd unit that runs the headless CLI with its own config.
+
+## Development
+
+- `go build ./...` — build
+- `go test ./...` — tests
+- `golangci-lint run ./...` — lint
+- See `AGENTS.md` and `project.md` for workflow and milestone history.
+
+## License
+
+GPL-2.0, matching the obs-teleport project whose protocol we implement.
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