All environment variables across all packages — what they control, safe defaults, and which are required before deploying.

Environment & Config

Server (`packages/server/.env`)

Variable	Required	Default	Description
`POSTGRES_USER`	Yes	—	Postgres username
`POSTGRES_PASSWORD`	Yes	—	Postgres password
`POSTGRES_DB`	Yes	—	Postgres database name
`JWT_SECRET`	Yes	`"dev-secret"`	Secret for signing JWTs. Use a long random string in production.
`DATABASE_URL`	Yes	—	Full Prisma connection string: `postgresql://<user>:<pass>@db:5432/<db>`
`PORT`	No	`3000`	Port the Fastify server listens on

The DATABASE_URL host must be db (the Docker Compose service name) when running in Docker. Use localhost for running the server outside Docker.

Example `.env`

POSTGRES_USER=skytalk
POSTGRES_PASSWORD=skytalkpass
POSTGRES_DB=skytalk
JWT_SECRET=dev-jwt-secret-change-in-prod
DATABASE_URL=postgresql://skytalk:skytalkpass@db:5432/skytalk

The .env file is not in source control. It must be created manually on each machine. Never commit real credentials.

Mobile App (`packages/mobile/.env.local`)

Variable	Default	Description
`EXPO_PUBLIC_MOCK_MODE`	`true`	`true` = MockRelaySocket loopback. `false` = connect to real server.
`EXPO_PUBLIC_API_URL`	`http://localhost:3000`	Base URL for REST API calls
`EXPO_PUBLIC_WS_URL`	`ws://localhost:9999`	WebSocket relay endpoint
`EXPO_PUBLIC_DLS140_URL`	`http://192.168.111.1:3000`	DLS-140 local REST API
`EXPO_PUBLIC_TALKGROUP`	`alpha`	Default talkgroup ID on connect
`EXPO_PUBLIC_DEVICE_ID`	random per launch	Device UUID for floor control. Set explicitly for consistent arbitration.

All variables use the EXPO_PUBLIC_ prefix — required for Expo to expose them to the JavaScript bundle.

For real server connection

EXPO_PUBLIC_MOCK_MODE=false
EXPO_PUBLIC_API_URL=http://134.122.32.45:3000
EXPO_PUBLIC_WS_URL=ws://134.122.32.45:3000/ws
EXPO_PUBLIC_DLS140_URL=http://192.168.111.1:3000
EXPO_PUBLIC_DEVICE_ID=<stable-device-uuid>

JWT Shape

All protected routes validate a JWT in the Authorization: Bearer <token> header.

{
  "sub": "<userId>",
  "username": "<username>",
  "role": "admin | user",
  "iat": 1234567890
}

sub is the user's UUID from the User table. role determines access to admin endpoints. JWTs are currently issued without exp (no expiry) during development — add expiresIn to the app.jwt.sign() call in src/routes/auth.ts before production deployment.

WebSocket Connection

ws://134.122.32.45:3000/ws?token=<jwt>

The JWT is passed as a query parameter on the initial HTTP upgrade request. The server verifies it before accepting the WebSocket connection. Invalid or missing tokens result in a 1008 Policy Violation close code.

Docker Compose Variable Interpolation

docker-compose.yml reads variables from .env via Docker Compose's built-in interpolation. The server container receives DATABASE_URL, JWT_SECRET, and PORT as process environment variables. Postgres receives POSTGRES_USER, POSTGRES_PASSWORD, and POSTGRES_DB.

# docker-compose.yml (simplified)
services:
  db:
    environment:
      POSTGRES_USER: ${POSTGRES_USER}
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
      POSTGRES_DB: ${POSTGRES_DB}
  server:
    environment:
      DATABASE_URL: postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@db:5432/${POSTGRES_DB}
      JWT_SECRET: ${JWT_SECRET}

Environment & Config

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