progressively working deploy scenario

.env.example

@@ -1,9 +1,24 @@
 # KMountain Flower Radio Station — Environment Variables
-# Copy this file to .env and fill in the values. Do NOT commit .env.
+# Copy this file to .env and adjust values for your environment. Do NOT commit .env.
 
-# PostgreSQL connection string (backend)
-# Format: postgresql+asyncpg://user:password@host:port/database
-KMTN_DATABASE_URL=postgresql+asyncpg://postgres:postgres@localhost:5432/kmountain
+# ── Database (db service) ─────────────────────────────────────────────
+POSTGRES_DB=kmountain
+POSTGRES_USER=postgres
+POSTGRES_PASSWORD=postgres
 
-# CORS allowlist for the backend (JSON array of allowed origins)
-KMTN_CORS_ORIGINS=["http://localhost:4200"]
+# ── Backend API (api service) ─────────────────────────────────────────
+# Database connection string. Use postgresql+asyncpg for PostgreSQL, sqlite+aiosqlite for local dev without a DB.
+KMTN_DATABASE_URL=postgresql+asyncpg://postgres:postgres@db:5432/kmountain
+
+# JSON array of allowed CORS origins.
+# Dev: include localhost variants. Prod: your actual domain(s).
+KMTN_CORS_ORIGINS='["http://localhost:4200", "http://localhost"]'
+
+# Environment name. Set to "production" to disable the admin router.
+# KMTN_ENV=development
+
+# ── Frontend (frontend service) ───────────────────────────────────────
+# URL of the API backend that nginx should proxy /api/ requests to.
+# Dev (Docker Compose): http://api:8000  (DNS resolves to the api container)
+# Prod: https://api.yourdomain.com  (or whatever your API endpoint is)
+API_UPSTREAM=http://api:8000