Getting Started

Spool is a Tauri 2 desktop app: a Rust backend (tauri/src-tauri/) paired with a SvelteKit 5 frontend (tauri/src/). Windows and Linux are both primary targets (notably the gaming-handheld distros — Bazzite, CachyOS, SteamOS).

Prerequisites

• Rust (stable toolchain)
• Bun for the frontend
• Tauri’s platform prerequisites — see the Tauri prerequisites guide
• Linux only: the WebView + tray system libraries — libwebkit2gtk-4.1-dev, libappindicator3-dev, and librsvg2-dev (add patchelf and xdg-utils if you build an AppImage — the bundler copies /usr/bin/xdg-open into it). umu-launcher (umu-run) on the host is optional — only needed to test the Proton runner, and is the one Linux dependency that is not bundled.

Bundled sidecars

Spool shells out to ludusavi and rclone, which ship as Tauri sidecars — end users never install them separately. For development you fetch them once into tauri/src-tauri/binaries/:

cd tauri
bun run download-sidecars

You need these before anything that compiles the backend — tauri dev, tauri build, and the local checks — because Tauri verifies the sidecar binaries exist at build time.

Install & run

All commands run from tauri/ unless noted.

cd tauri

# Install frontend dependencies (first time, or after package.json changes)
bun install

# Fetch the bundled sidecars (first time — see "Bundled sidecars" above)
bun run download-sidecars

# Run the app in development (hot-reload frontend + auto-rebuild backend)
bun tauri dev

Build a release binary

tauri/src-tauri/target/release/spool.exe

cd tauri
bun tauri build
# Output:
#   tauri/src-tauri/target/release/bundle/nsis/Spool_<version>_x64-setup.exe

On Linux the release build produces an AppImage — Spool_*_amd64.AppImage on x86_64, Spool_*_aarch64.AppImage on ARM64. Tauri cannot cross-compile ARM AppImages, so an aarch64 build has to run on an ARM machine.

Run the checks locally

CI fails on any clippy warning, so run these before pushing.

Sidecars required

cargo check, cargo clippy, and cargo test compile the backend, so the bundled sidecars must be present first — run bun run download-sidecars (see Bundled sidecars) if you haven’t already.

# Backend (from tauri/src-tauri)
cargo check
cargo clippy --all-targets -- -D warnings
cargo test

# Frontend (from tauri/)
bun run check     # svelte-check
bun run lint      # ESLint
bun run test      # Vitest unit tests

End-to-end tests drive a real Tauri window via tauri-driver + WebdriverIO:

cd tauri
bun run test:e2e  # builds the app then runs the WebDriver suite
# Headless Linux: xvfb-run -a bun run e2e

Where things live

Path	What it is
tauri/src-tauri/src/	Rust backend (persistence, subprocess orchestration, OS integration)
tauri/src/	SvelteKit frontend (routes + lib/)
server/	Self-hostable Hono sync server
decky/	Companion Decky Loader plugin
docs-site/	This documentation site

See Architecture → Overview for the full module map.