Two faults, both present since v0.0.1, both found and confirmed on a device. Audio track (DR-258). Jellyfin builds a transcode around one AudioStreamIndex, so the alternate tracks are not in the stream that arrives — but the native path only ever called setAudioTrack(n), which indexes ExoPlayer's audio track *groups*. On Android that is the common case, since any source whose default audio codec the device cannot decode is transcoded: logcat showed ExoPlayer holding `Audio tracks: 1` while the menu listed every track in the file, so each selection warned `Invalid audio track index` and was dropped, leaving the default track playing with nothing in the UI saying so. determine_audio_track_switch_strategy now decides by whether the stream in front of the engine carries the track at all — a direct play still selects in place, a transcode is re-negotiated at the chosen index and resumed. Where it resumes is the player's answer rather than the UI's: the native path has no <video> element to read, so it sends no position, and defaulting that to zero re-opened the film at the beginning (caught on device before it shipped). Subtitles (DR-259). The URL was missing its `Stream.` route segment, so every sideloaded subtitle 404ed; since media3 1.5 a sideloaded text track only becomes a track group once its file is parsed, so 42 failed fetches left ExoPlayer with no text tracks and selection warned `available: 0`. Verified against a live server: the built URL answers 404, the corrected one 200. The tests that should have caught this asserted the shape of a mock helper that restated the format string instead of the URL the app requests — so the new test drives the repository itself, and failed red on the old URL.

JellyTau
A cross-platform Jellyfin client built with Tauri, SvelteKit, and TypeScript.
Business logic lives in a Rust backend; a UI-rich Svelte frontend handles presentation and talks to it over Tauri's IPC. Targets Linux (libmpv) and Android (ExoPlayer).
Getting Started
This project uses bun as its package manager.
# Activate the Rust environment (fish shell)
source "$HOME/.cargo/env.fish"
# Install dependencies
bun install
# Run in development
bun run tauri dev
# Type-check the frontend
bun run check
# Build for Linux
bun run tauri build
# Build for Android
bun run tauri android build
For the full set of build, test, and Android helper scripts, see scripts/README.md.
Documentation
| Topic | Location |
|---|---|
| Architecture overview & subsystem docs | docs/architecture/ |
| Requirements, traceability & technical debt | docs/requirements.md |
| Build & release process | docs/build/build-release.md |
| Docker builds | docs/build/docker.md |
| Traceability tooling & CI | docs/traceability.md, docs/traceability-ci.md |
| Release checklist | docs/release-checklist.md |
| UX flows | docs/ux-flows.md |
| CI operations (builder image, secrets, runner) | docs/build/ci-operations.md |
Contributing
CONTRIBUTING.md covers the setup, the gates a change has to pass, and the two rules that catch people out (bug fixes start with a failing test; Jellyfin's taxonomy stays in Rust). Please also read the Code of Conduct.
Found a security problem? Do not open an issue — see SECURITY.md.
Verifying a download
Every release publishes SHA256SUMS covering all of its artifacts, plus an SBOM
of what went into the build:
sha256sum -c SHA256SUMS
Desktop builds update themselves from Settings → Updates, verifying each payload against JellyTau's signing key before installing. Android installs are handled by the system installer, so the app links to the releases page instead.
Recommended IDE Setup
VS Code + Svelte + Tauri + rust-analyzer.
License
MIT