Self-hosted
The same karaoke engine as the desktop app, as a container. The server that already holds your music puts lyrics on any TV in the house and turns every phone into a remote. Try 5 songs free, then $19.99 once.
docker run -d --name beltr -p 8477:8477 \
-e PUID=1000 -e PGID=1000 -e TZ=UTC \
--restart unless-stopped \
-v /path/to/appdata/beltr:/config \
-v /path/to/bulk/beltr-library:/library \
-v /path/to/beltr-cache:/cache \
-v /path/to/your/music:/media:ro \
ghcr.io/casavargas/beltr:latestSet PUID and PGID to the user that owns your media folder; on Unraid that is 99 and 100.
Or with Compose (compose file and .env.example on GitHub):
cp .env.example .env
docker compose --profile cpu up -dThen open http://<server>:8477/dashboard to add music, and put /tv on the screen you sing at. Phones scan the QR code on the TV.
| Tag | Hardware | Platforms | Size | Notes |
|---|---|---|---|---|
latest | CPU | linux/amd64 + linux/arm64 | about 1.2 GB | Every box |
latest-cuda | NVIDIA GPU | linux/amd64 | about 5 GB | --gpus all; runs fine with no GPU too |
latest-openvino | Intel iGPU or Arc | linux/amd64 | about 2 GB | --device /dev/dri |
Version tags pin a release (for example 1.62.0, or 1.62 for the newest patch of that line); latest follows releases.
Install from Community Applications: Apps tab, search "Beltr". CPU, NVIDIA and Intel GPU templates.
Find Beltr in Community ApplicationsA Beltr package for the TrueNAS community train has been requested and is not in the catalog yet (app request). Until it is accepted, run Beltr on TrueNAS SCALE as a custom app with the compose file above; it uses the same volumes and port. This page will say so when the catalog listing is live.
It works, and it is the slow way to run Beltr on a Mac. Pull latest under Docker Desktop or OrbStack and you get the arm64 image automatically. Inside the Linux VM there is no CoreML and no GPU, so vocal separation runs on the CPU: on an M4 Mac mini a 3:11 song took 121 seconds, against about 11 seconds in the native Mac app. Fine for a party server that prepares songs in the background. If you just want the fastest Beltr on that Mac, download the Mac app instead.
Keep /library on a named volume or a VirtioFS bind mount; there is no --device or --gpus to pass.
| Path | What lives there | Storage |
|---|---|---|
/config | app state, settings, logs, license.key | small, SSD |
/library | separated stems, imported audio, clips | large, bulk storage |
/media | your own music, read-only | wherever it lives |
/cache | model weights, about 2 GB after first run | SSD |
Port 8477. Put your key in BELTR_LICENSE_KEY or drop it at /config/license.key; it activates once against this install and then works offline. Leave it blank for the 5-song trial.