UltimateSlice

The AI connectable video editor.

UltimateSlice is a Final Cut Pro–inspired non-linear video editor built with Rust and GTK4, powered by GStreamer for media playback and export.

Built in MCP server allows for AI collaboration.

Features

✅ Implemented

• GTK4 application scaffold with dark theme styling
• Media library import with duration probing (video/audio/image)
• Source monitor with playback, scrubber, in/out marks, and timecode
• Timeline with multi-track rows, zoom/pan, clip selection, trim, move, razor
• Undo/Redo command history
• Inspector panel for selected clip properties
• MP4/H.264 export via GStreamer pipeline
• FCPXML 1.10–1.14 import + 1.14 export
• Optional MCP server (--mcp) for JSON-RPC control

Third-Party Crates and Libraries

UltimateSlice uses open-source crates and runtime libraries, including:

• gtk4-rs / gdk4 / gio / glib — LGPL-2.1-or-later
• gstreamer-rs + GStreamer — LGPL-2.1-or-later
• quick-xml — MIT
• serde / serde_json — MIT OR Apache-2.0
• uuid — MIT OR Apache-2.0
• anyhow / thiserror / log / env_logger — MIT OR Apache-2.0
• FFmpeg (tooling/runtime) — LGPL-2.1-or-later (Flatpak build enables GPL options)
• x264 (Flatpak build dependency) — GPL-2.0-or-later

For exact versions and full dependency tree, see Cargo.toml, Cargo.lock, and io.github.kmwallio.ultimateslice.yml.

🔜 Planned

See ROADMAP.md for upcoming features like thumbnails, audio waveforms, multi-track editing, transitions, and a program monitor.

Project Structure

See docs/ARCHITECTURE.md for the full layout and design notes. Highlights:

• src/app.rs – GTK application setup and CSS loading
• src/model/ – core data model (Project, Track, Clip, MediaItem)
• src/media/ – playback, thumbnails, and export
• src/ui/ – GTK widgets (timeline, inspector, media browser, preview)
• src/fcpxml/ – FCPXML parser/writer

Requirements

• Rust (edition 2021)
• GTK4 development libraries
• GStreamer + plugins for playback and export

On Linux, install GTK4 and GStreamer via your distribution packages.

Build & Run

# from the project root
cargo build
cargo run

To run with MCP server enabled:

cargo run -- --mcp

Python MCP Socket Client

When using the MCP socket transport (running instance), you can use the Python bridge client:

python3 tools/mcp_socket_client.py

Optional socket override:

python3 tools/mcp_socket_client.py --socket /tmp/ultimateslice-mcp.sock

The client reads JSON-RPC lines from stdin and writes responses to stdout. See docs/user/python-mcp.md for complete command examples.

Flatpak

A Flatpak manifest is provided at io.github.kmwallio.ultimateslice.yml.

flatpak-builder build-dir io.github.kmwallio.ultimateslice.yml --user --install --force-clean
flatpak run io.github.ultimateslice

Notes

• GTK4 callbacks cannot unwind panics. Avoid RefCell double-borrows in UI callbacks.
• The project shares a single GStreamer playbin for source and timeline playback.

License

This project is licensed under the GNU General Public License v3.0.