Configuration

The server reads config from a config.json file and/or REALM_-prefixed environment variables. Environment variables always take priority over config.json.

Config file

Create a config.json in the same directory as your Compose file:

{
  "identity": {
    "name": "My Realm Server",
    "description": "A community server",
    "publicHost": "my-server.example.com",
    "password": null
  },
  "coreApi": {
    "baseUrl": "https://api.realmvoice.app"
  },
  "storage": {
    "mongoUrl": "mongodb://mongo:27017/realm_dedicated"
  },
  "voice": {
    "rtpMin": 40000,
    "rtpMax": 49999
  },
  "webrtc": {
    "listenIp": "0.0.0.0",
    "announcedIp": null
  },
  "attachments": {
    "provider": "local",
    "maxFileSizeMb": 25,
    "localPath": "./uploads"
  },
  "logLevel": "info"
}

Mount it into the container:

# docker-compose.server.yml
volumes:
  - ./config.json:/app/apps/server/config.json:ro

Identity

Realm API

Storage

Voice

WebRTC

HTTPS / TLS

The web client at realmvoice.app is served over HTTPS, and browsers refuse to open an insecure http:// / ws:// connection from an HTTPS page (a "mixed content" error). So a server must be reachable over https:// for the web client to connect.

You have two options:

• Built-in auto-HTTPS (tls.enabled). Set tls.enabled and a publicHost, then start the bundled Caddy sidecar. Caddy obtains and renews a Let's Encrypt certificate automatically and the server registers itself on port 443. No reverse proxy of your own to configure.
• Your own reverse proxy. Terminate TLS with Caddy/nginx/Traefik in front of the server yourself and set identity.publicPort to 443.

Enable the built-in option by opting into the tls Compose profile:

# config.json: { "identity": { "publicHost": "my-server.example.com" }, "tls": { "enabled": true } }
# or: REALM_IDENTITY_PUBLIC_HOST=my-server.example.com REALM_TLS_ENABLED=true
docker compose -f docker-compose.server.yml --profile tls up -d

Open ports 80 and 443 on your firewall (80 is needed for the certificate challenge).

Attachments

The server supports image and video attachments in chat. Uploads are stored on the local filesystem by default.

Supported formats: PNG, JPEG, GIF, WebP, SVG, MP4, WebM, MOV

Images are automatically compressed and thumbnailed. Videos are stored as-is with no server-side transcoding.

Local storage (default)

{
  "attachments": {
    "provider": "local",
    "maxFileSizeMb": 25,
    "localPath": "./uploads"
  }
}

The Docker Compose setup mounts a volume at /data which includes the uploads/ directory. Files survive container restarts and updates without any extra configuration.

S3-compatible storage

Use S3 for CDN delivery or if you'd rather not store files on disk:

{
  "attachments": {
    "provider": "s3",
    "maxFileSizeMb": 50,
    "s3": {
      "bucket": "my-realm-uploads",
      "region": "us-east-1",
      "endpoint": "https://abc123.r2.cloudflarestorage.com",
      "accessKeyId": "AKIA...",
      "secretAccessKey": "wJal..."
    }
  }
}

Or via environment variables:

REALM_ATTACHMENTS_PROVIDER=s3
REALM_ATTACHMENTS_S3_BUCKET=my-realm-uploads
REALM_ATTACHMENTS_S3_REGION=us-east-1
REALM_ATTACHMENTS_S3_ENDPOINT=https://abc123.r2.cloudflarestorage.com
REALM_ATTACHMENTS_S3_ACCESS_KEY_ID=AKIA...
REALM_ATTACHMENTS_S3_SECRET_ACCESS_KEY=wJal...

Compatible with Cloudflare R2, MinIO, and AWS S3. For R2 and MinIO, set endpoint to the custom endpoint URL.

Logging

Full environment variable reference