VideoTogether

VideoTogether is a private movie sharing project designed for two people in the same LAN.

The host imports a local video file, processes it into HLS with ffprobe and ffmpeg, creates a private room link, and shares that link with a second viewer. The viewer does not need the desktop app and can join directly from a browser.

The current primary workflow is: run locally, share quickly, and keep playback synchronized for two people.

Features

Implemented today:

• Local video import
• Media probing with ffprobe
• HLS transcoding and segmentation with ffmpeg
• Subtitle import and conversion for .srt, .vtt, and .ass
• Private room creation and shareable links
• Browser-based room playback
• Two-person synchronized play / pause / seek
• Room-level subtitle selection sync
• Participant presence and reconnect recovery
• Tauri desktop host dashboard
• One-command host startup flow

Repository Layout

apps/
  desktop/   Tauri desktop host dashboard
  server/    Fastify + Socket.IO + SQLite + FFmpeg backend
  web/       Browser playback and room UI
packages/
  shared-types/
  shared-schemas/
  shared-utils/
storage/
  media/     uploaded source videos
  hls/       generated HLS manifests and segments
  subtitles/ converted subtitle files
  db/        SQLite database
  temp/      temporary processing directory
infra/
  docker-compose.yml
  scripts/   startup, shutdown, and packaging scripts

For Users (Windows)

You can install VideoTogether directly on Windows:

1. Download the latest Windows installer (.exe) from the Releases page.
2. Run the installer and follow the instructions.
3. Configure your ip in .env.example Launch the app and configure your LAN IP
4. Start watching videos with your friends!

IP configuation

Open the terminal of your choice, say, powershell. Input the command:

> ipconfig

You'll get your ipv4 address in the result that looks something like this:

Ethernet adapter Ethernet:

   Connection-specific DNS Suffix  . :
   IPv6 Address. . . . . . . . . . . : xxxx:xxxx:xxxx:xxxx::xxxx
   Link-local IPv6 Address . . . . . : fe80::xxxx:xxxx:xxxx:xxxx%xx
   IPv4 Address. . . . . . . . . . . : 10.x.x.x
   Subnet Mask . . . . . . . . . . . : 255.255.240.0
   Default Gateway . . . . . . . . . : fe80::xxxx:xxxx:xxxx:xxxx%xx
                                       10.x.x.x

You need to copy the IPv4 address, and paste it into .env.example enter it into the LAN IP text box:

...
LAN_IP=10.x.x.x
...

And after that, you're done!

Note about Zerotier

As is stated later, zerotier is required to share the movie with someone not in the same physical LAN. In this case, you'll need to :

1. Download zerotier
2. Join the same virtual LAN with whom you'd like to share the movie with
3. Set the LAN_IP in .env.example as the ip you assigned yourself in the zerotier panel.

Once you've successfully configured zerotier, you should see something like this after running ipconfig:

Ethernet adapter ZeroTier One [xxxxxxxxxxxxxxxx]:

   Connection-specific DNS Suffix  . :
   Link-local IPv6 Address . . . . . : fe80::xxxx:xxxx:xxxx:xxxx%xx
   IPv4 Address. . . . . . . . . . . : 10.x.x.x
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 25.x.x.x

The IPv4 in this result should match the ip you assigned yourself in zerotier.

For Developers

Requirements

You need these on the host machine:

• Node.js 22+
• npm 11+
• ffmpeg
• ffprobe
• Rust / Tauri Windows build prerequisites
  • required for desktop development or packaging
• Docker Desktop
  • only required when USE_DOCKER=true

Environment Variables

Start from .env.example.

Important variables:

• USE_DOCKER
  • controls whether the host startup script uses Docker for the server
  • default: false
• HOST
  • server bind address
  • use 0.0.0.0 if guests on your LAN or ZeroTier need to connect
  • default: 0.0.0.0
• PORT
  • local server port used by the production-like host flow
  • default: 3000
• PUBLIC_PROTOCOL
  • protocol used when deriving public share URLs
  • default: http
• PUBLIC_HOST
  • hostname used when deriving public share URLs
  • default: localhost
• WEB_DEV_PORT
  • Vite development server port used by npm run dev
  • default: 5173
• LAN_IP
  • fixed IPv4 used by the desktop app when generating LAN room URLs
  • set this to the exact IPv4 you want to expose, such as your ZeroTier IPv4
• FFMPEG_PATH
  • path to the ffmpeg executable
• FFPROBE_PATH
  • path to the ffprobe executable

Current .env.example defaults assume:

• development web URL: http://localhost:5173
• production-like local host flow: http://localhost:3000
• Docker disabled by default
• LAN URL generation uses only the explicit LAN_IP value

Install Dependencies

From the repository root:

npm install

Recommended Usage

1. Start the host flow

npm run host:start

This command will:

• build the production web assets
• build the production server assets
• start the local production server
• launch the Tauri desktop host dashboard

Default behavior:

• Docker is not used
• share links point to http://localhost:3000
• LAN room URLs are only generated from LAN_IP

To stop the host flow:

npm run host:stop

This stops the background local server process tree started by host:start.

If you only want the local server and do not want to launch the desktop app:

npm run host:start -- -SkipDesktop

2. Use the desktop host dashboard

Recommended host flow inside the desktop app:

1. Select a local video file, or reuse an existing media item from the library.
2. Wait for processing to complete.
3. Optionally upload subtitle files.
4. Choose the room's initial subtitle.
5. Set the host display name and room expiration.
6. Create the room.
7. Copy the share link and send it to the second viewer.

The desktop app also provides:

• processing status
• media metadata
• room status
• participant presence
• subtitle updates
• room closing
• unused media deletion
• local URL and LAN URL copy actions

If you want the desktop app to generate LAN URLs, set LAN_IP to the exact IPv4 you want to use, for example your ZeroTier IPv4. The app does not auto-detect LAN IPs.

If the host can open the room locally but a guest cannot, first check that HOST=0.0.0.0 and then send the guest the LAN room URL instead of a localhost URL.

3. Guest usage

The guest does not need the desktop app.

They only need to:

1. Open the room link in a browser.
2. Enter a display name.
3. Join the room.
4. Watch the synchronized stream.

Docker Is Optional

If you want host:start to run the server through Docker, set:

USE_DOCKER=true

Then run the same command:

npm run host:start

In this mode the script will:

• use infra/docker-compose.yml
• run the server inside a container
• mount the local storage/* directories
• still run the desktop app on the host machine

Local Development Mode

If you want to work with separate dev processes for web, server, and desktop:

npm run dev:server
npm run dev:web
npm run dev:desktop

Default development endpoints:

• API: http://localhost:3000
• Web: http://localhost:5173
• Desktop dev shell: npm run dev:desktop

Common Commands

• npm run host:start
  • builds the production web and server bundles, starts the local host server, and launches the Tauri desktop dashboard
• npm run host:stop
  • stops the background server process tree started by host:start
• npm run host:start -- -SkipDesktop
  • starts the local host server only, without launching the desktop app
• npm run package:desktop
  • builds the Tauri desktop installer bundles
• npm run dev:server
  • runs the Fastify server in development watch mode
• npm run dev:web
  • runs the Vite web app in development mode
• npm run dev:desktop
  • runs the Tauri desktop app in development mode
• npm run build:host
  • builds production assets for apps/web and apps/server
• npm run lint
  • runs ESLint across all workspaces that define a lint script
• npm run typecheck
  • runs TypeScript type checking across all workspaces without emitting build artifacts

Routes and Endpoints

Health and diagnostics:

• GET /health
• GET /api/system/status

Room endpoints:

• POST /api/rooms
• GET /api/rooms/:token
• POST /api/rooms/:token/join
• POST /api/rooms/:token/subtitle
• POST /api/rooms/:token/close

Media endpoints:

• GET /api/media
• POST /api/media/import
• GET /api/media/:id
• DELETE /api/media/:id
• POST /api/media/:id/process
• POST /api/media/:id/subtitles
• GET /api/media/:id/subtitles

Static playback assets:

• GET /media/:mediaId/*
• GET /subtitles/:subtitleId.vtt
• GET /
• GET /room/:token

Pro Tip

To share video with people not within the same physical LAN, you can use projects like zerotier

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details.

This project uses FFmpeg which is licensed under the GNU Lesser General Public License (LGPL) version 2.1 or later.