diff --git a/.env.example b/.env.example
index 00c9816..a8c9992 100644
--- a/.env.example
+++ b/.env.example
@@ -22,6 +22,8 @@ DATABASE_URL=postgresql+asyncpg://paperdynasty:your-password@your-db-server:5432
 DISCORD_CLIENT_ID=your-discord-client-id
 DISCORD_CLIENT_SECRET=your-discord-client-secret
 DISCORD_REDIRECT_URI=http://localhost:3000/auth/callback
+DISCORD_SERVER_REDIRECT_URI=http://localhost:8000/api/auth/discord/callback/server
+FRONTEND_URL=http://localhost:3000
 
 # ============================================================================
 # League REST APIs
@@ -39,9 +41,28 @@ PD_API_KEY=your-pd-api-key
 # ============================================================================
 CORS_ORIGINS=http://localhost:3000,http://localhost:3001
 
+# ============================================================================
+# Access Control
+# ============================================================================
+# Comma-separated Discord user IDs allowed access
+# Leave empty or use * for all users (dev only!)
+ALLOWED_DISCORD_IDS=
+
+# ============================================================================
+# WebSocket Settings
+# ============================================================================
+WS_HEARTBEAT_INTERVAL=30
+WS_CONNECTION_TIMEOUT=60
+
 # ============================================================================
 # Redis (optional - for caching)
 # ============================================================================
 # When using Docker Compose, Redis is automatically available at redis://redis:6379
 # When running locally, use redis://localhost:6379
-# REDIS_URL=redis://localhost:6379
\ No newline at end of file
+# REDIS_URL=redis://localhost:6379
+
+# ============================================================================
+# Frontend Dev Server
+# ============================================================================
+# Comma-separated hostnames for Vite dev server external access
+NUXT_ALLOWED_HOSTS=localhost,127.0.0.1
\ No newline at end of file
diff --git a/CLAUDE.md b/CLAUDE.md
index ad1d5a6..3c90bcf 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -81,9 +81,52 @@ strat-gameplay-webapp/
 │   └── tests/
 ├── frontend-sba/         # SBA League Nuxt app
 ├── frontend-pd/          # PD League Nuxt app
-└── shared-components/    # Shared Vue components (optional)
+├── docker-compose.yml    # Dev orchestration (all services)
+├── docker-compose.prod.yml # Production overrides
+└── .env.example          # Root environment template
 ```
 
+## Environment Configuration
+
+### Multi-Domain Support
+The project is fully environment-driven for deployment to different domains. All URLs and credentials are externalized.
+
+### Environment Files
+| File | Purpose |
+|------|---------|
+| `.env.example` | Root template - copy to `.env` |
+| `backend/.env.example` | Backend-specific template |
+| `frontend-sba/.env.example` | SBA frontend template |
+| `frontend-pd/.env.example` | PD frontend template |
+
+### Key Environment Variables
+
+**Backend** (in `backend/.env`):
+- `DATABASE_URL` - PostgreSQL connection string
+- `DISCORD_CLIENT_ID/SECRET` - OAuth credentials
+- `DISCORD_SERVER_REDIRECT_URI` - Server-side OAuth callback
+- `FRONTEND_URL` - Frontend base URL for redirects
+- `CORS_ORIGINS` - Allowed origins (comma-separated)
+- `ALLOWED_DISCORD_IDS` - User whitelist (comma-separated, empty = all)
+
+**Frontend** (in `frontend-*/env`):
+- `NUXT_PUBLIC_API_URL` - Backend API URL
+- `NUXT_PUBLIC_WS_URL` - WebSocket URL
+- `NUXT_PUBLIC_DISCORD_CLIENT_ID` - OAuth client ID (public)
+- `NUXT_PUBLIC_DISCORD_REDIRECT_URI` - OAuth callback URL
+- `NUXT_ALLOWED_HOSTS` - Vite dev server allowed hosts (comma-separated)
+
+### Docker Deployment
+```bash
+# Development
+docker compose up
+
+# Production
+docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d
+```
+
+See `README.md` "Multi-Domain Deployment" section for full checklist.
+
 ## Development Guidelines
 
 ### Code Quality
diff --git a/README.md b/README.md
index c9b8260..384e9d2 100644
--- a/README.md
+++ b/README.md
@@ -208,6 +208,47 @@ Copy `.env.example` to `.env` and configure:
 - `REDIS_URL` - Redis connection (auto-configured in Docker)
 - `CORS_ORIGINS` - Allowed origins (defaults to localhost:3000,3001)
 
+---
+
+## Multi-Domain Deployment
+
+This project supports deployment to multiple domains. Key environment variables to configure:
+
+### Backend Variables
+| Variable | Description | Example |
+|----------|-------------|---------|
+| `FRONTEND_URL` | Frontend base URL for OAuth redirects | `https://yourdomain.com` |
+| `DISCORD_REDIRECT_URI` | Legacy Discord callback | `https://yourdomain.com/auth/callback` |
+| `DISCORD_SERVER_REDIRECT_URI` | Server-side Discord callback | `https://yourdomain.com/api/auth/discord/callback/server` |
+| `CORS_ORIGINS` | Allowed CORS origins (comma-separated) | `https://yourdomain.com,https://api.yourdomain.com` |
+| `ALLOWED_DISCORD_IDS` | Whitelist of Discord user IDs | `123456,789012` or empty for all |
+
+### Frontend Variables
+| Variable | Description | Example |
+|----------|-------------|---------|
+| `NUXT_PUBLIC_API_URL` | Backend API base URL | `https://yourdomain.com` |
+| `NUXT_PUBLIC_WS_URL` | WebSocket base URL | `https://yourdomain.com` |
+| `NUXT_PUBLIC_DISCORD_REDIRECT_URI` | OAuth callback URL | `https://yourdomain.com/auth/callback` |
+| `NUXT_ALLOWED_HOSTS` | Vite dev server allowed hosts (comma-separated) | `yourdomain.com,localhost` |
+
+### Production Deployment
+
+```bash
+# Using Docker Compose with production overrides
+docker-compose -f docker-compose.yml -f docker-compose.prod.yml up -d
+```
+
+### Domain Deployment Checklist
+
+When deploying to a new domain:
+1. [ ] Update Discord OAuth redirect URIs in [Discord Developer Portal](https://discord.com/developers/applications)
+2. [ ] Copy `.env.example` files to `.env` and configure all URLs
+3. [ ] Update `CORS_ORIGINS` to include new domain
+4. [ ] Add domain to `NUXT_ALLOWED_HOSTS` (if using dev server externally)
+5. [ ] Configure reverse proxy (Nginx/NPM) to route traffic
+
+---
+
 ## Available Services
 
 When running, the following services are available:
diff --git a/backend/CLAUDE.md b/backend/CLAUDE.md
index 09c2347..329abe2 100644
--- a/backend/CLAUDE.md
+++ b/backend/CLAUDE.md
@@ -75,14 +75,36 @@ now = pendulum.now('UTC')
 - **Database**: paperdynasty_dev
 - **Connection**: `postgresql+asyncpg://...`
 
-### Required .env Variables
+### Environment Variables
+Copy `.env.example` to `.env` and configure. Key variables:
+
 ```bash
-DATABASE_URL=postgresql+asyncpg://...
-SECRET_KEY=your-secret-key
-DISCORD_CLIENT_ID=...
-DISCORD_CLIENT_SECRET=...
+# Required
+DATABASE_URL=postgresql+asyncpg://user:pass@host:5432/db
+SECRET_KEY=your-secret-key-min-32-chars
+DISCORD_CLIENT_ID=your-discord-client-id
+DISCORD_CLIENT_SECRET=your-discord-client-secret
+
+# OAuth URLs (update for your domain)
+DISCORD_REDIRECT_URI=http://localhost:3000/auth/callback
+DISCORD_SERVER_REDIRECT_URI=http://localhost:8000/api/auth/discord/callback/server
+FRONTEND_URL=http://localhost:3000
+
+# Access Control
+ALLOWED_DISCORD_IDS=  # Comma-separated user IDs, empty = all users
+
+# CORS (JSON array format)
+CORS_ORIGINS=["http://localhost:3000","http://localhost:3001"]
+
+# League APIs
+SBA_API_URL=https://api.sba.manticorum.com
+SBA_API_KEY=your-sba-api-key
+PD_API_URL=https://pd-api.example.com
+PD_API_KEY=your-pd-api-key
 ```
 
+**Multi-Domain Deployment**: When deploying to a new domain, update `FRONTEND_URL`, `DISCORD_*_REDIRECT_URI`, and `CORS_ORIGINS`. See root `README.md` for full checklist.
+
 ### Python Environment
 - **Version**: Python 3.13.3
 - **Package Manager**: UV (fast, reliable)
diff --git a/docker-compose.prod.yml b/docker-compose.prod.yml
new file mode 100644
index 0000000..c87af15
--- /dev/null
+++ b/docker-compose.prod.yml
@@ -0,0 +1,28 @@
+# Production overrides for Paper Dynasty Game Engine
+# Usage: docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d
+
+services:
+  backend:
+    build:
+      target: production
+    environment:
+      - APP_ENV=production
+      - DEBUG=false
+    restart: always
+
+  frontend-sba:
+    build:
+      target: production
+    environment:
+      - NODE_ENV=production
+    restart: always
+
+  frontend-pd:
+    build:
+      target: production
+    environment:
+      - NODE_ENV=production
+    restart: always
+
+  redis:
+    restart: always
diff --git a/docker-compose.yml b/docker-compose.yml
index 7b10d68..12a6752 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -2,8 +2,6 @@
 # Use this for integration testing, demos, or when you want everything containerized
 # For daily dev, see README.md for local development workflow
 
-version: '3.8'
-
 services:
   # Redis cache (shared dependency)
   redis:
@@ -51,6 +49,17 @@ services:
 
       # CORS
       - CORS_ORIGINS=http://localhost:3000,http://localhost:3001
+
+      # Server-side OAuth
+      - FRONTEND_URL=${FRONTEND_URL:-http://localhost:3000}
+      - DISCORD_SERVER_REDIRECT_URI=${DISCORD_SERVER_REDIRECT_URI:-http://localhost:8000/api/auth/discord/callback/server}
+
+      # Access Control
+      - ALLOWED_DISCORD_IDS=${ALLOWED_DISCORD_IDS:-}
+
+      # WebSocket Settings
+      - WS_HEARTBEAT_INTERVAL=${WS_HEARTBEAT_INTERVAL:-30}
+      - WS_CONNECTION_TIMEOUT=${WS_CONNECTION_TIMEOUT:-60}
     depends_on:
       redis:
         condition: service_healthy
@@ -79,6 +88,7 @@ services:
       - NUXT_PUBLIC_WS_URL=http://localhost:8000
       - NUXT_PUBLIC_DISCORD_CLIENT_ID=${DISCORD_CLIENT_ID}
       - NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3000/auth/callback
+      - NUXT_ALLOWED_HOSTS=${NUXT_ALLOWED_HOSTS:-localhost,127.0.0.1}
     depends_on:
       backend:
         condition: service_healthy
@@ -103,6 +113,7 @@ services:
       - NUXT_PUBLIC_WS_URL=http://localhost:8000
       - NUXT_PUBLIC_DISCORD_CLIENT_ID=${DISCORD_CLIENT_ID}
       - NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3001/auth/callback
+      - NUXT_ALLOWED_HOSTS=${NUXT_ALLOWED_HOSTS:-localhost,127.0.0.1}
     depends_on:
       backend:
         condition: service_healthy
diff --git a/frontend-pd/.env.example b/frontend-pd/.env.example
new file mode 100644
index 0000000..a690c66
--- /dev/null
+++ b/frontend-pd/.env.example
@@ -0,0 +1,14 @@
+# PD League Frontend Configuration
+# Copy to .env and update with your values
+
+# API Configuration
+NUXT_PUBLIC_API_URL=http://localhost:8000
+NUXT_PUBLIC_WS_URL=http://localhost:8000
+
+# Discord OAuth (public client ID only - safe to expose)
+NUXT_PUBLIC_DISCORD_CLIENT_ID=your-discord-client-id
+NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3001/auth/callback
+
+# Vite Dev Server - Allowed external hosts (comma-separated)
+# Add your domain here for external access during development
+NUXT_ALLOWED_HOSTS=localhost,127.0.0.1
diff --git a/frontend-pd/CLAUDE.md b/frontend-pd/CLAUDE.md
index d7173d2..01672b2 100644
--- a/frontend-pd/CLAUDE.md
+++ b/frontend-pd/CLAUDE.md
@@ -257,16 +257,24 @@ export const useGameStore = defineStore('game', () => {
 ## Configuration
 
 ### Environment Variables
-Create `.env` file with:
+Copy `.env.example` to `.env` and configure:
+
 ```bash
-NUXT_PUBLIC_LEAGUE_ID=pd
-NUXT_PUBLIC_LEAGUE_NAME=Paper Dynasty
+# API endpoints
 NUXT_PUBLIC_API_URL=http://localhost:8000
 NUXT_PUBLIC_WS_URL=http://localhost:8000
+
+# Discord OAuth (public client ID - safe to expose)
 NUXT_PUBLIC_DISCORD_CLIENT_ID=your-client-id
 NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3001/auth/callback
+
+# Vite dev server allowed hosts (comma-separated)
+# Add your domain for external access
+NUXT_ALLOWED_HOSTS=localhost,127.0.0.1
 ```
 
+**Note**: `NUXT_ALLOWED_HOSTS` is read in `nuxt.config.ts` to configure Vite's `allowedHosts`. Required when accessing dev server through a reverse proxy or external domain.
+
 ### Nuxt Config
 ```typescript
 // nuxt.config.ts
diff --git a/frontend-pd/nuxt.config.ts b/frontend-pd/nuxt.config.ts
index ad069b3..3600613 100644
--- a/frontend-pd/nuxt.config.ts
+++ b/frontend-pd/nuxt.config.ts
@@ -16,6 +16,14 @@ export default defineNuxtConfig({
 
   devtools: { enabled: true },
 
+  // Vite config for external hostname access
+  // Configure NUXT_ALLOWED_HOSTS env var for your domains (comma-separated)
+  vite: {
+    server: {
+      allowedHosts: process.env.NUXT_ALLOWED_HOSTS?.split(',') || ['localhost', '127.0.0.1']
+    }
+  },
+
   typescript: {
     strict: true,
     typeCheck: true
diff --git a/frontend-sba/.env.example b/frontend-sba/.env.example
new file mode 100644
index 0000000..9722fc6
--- /dev/null
+++ b/frontend-sba/.env.example
@@ -0,0 +1,14 @@
+# SBA League Frontend Configuration
+# Copy to .env and update with your values
+
+# API Configuration
+NUXT_PUBLIC_API_URL=http://localhost:8000
+NUXT_PUBLIC_WS_URL=http://localhost:8000
+
+# Discord OAuth (public client ID only - safe to expose)
+NUXT_PUBLIC_DISCORD_CLIENT_ID=your-discord-client-id
+NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3000/auth/callback
+
+# Vite Dev Server - Allowed external hosts (comma-separated)
+# Add your domain here for external access during development
+NUXT_ALLOWED_HOSTS=localhost,127.0.0.1
diff --git a/frontend-sba/CLAUDE.md b/frontend-sba/CLAUDE.md
index 9a7032d..634f77f 100644
--- a/frontend-sba/CLAUDE.md
+++ b/frontend-sba/CLAUDE.md
@@ -58,14 +58,25 @@ npm run lint         # Lint code
 
 ## Configuration
 
-### Environment Variables (.env)
+### Environment Variables
+Copy `.env.example` to `.env` and configure:
+
 ```bash
-NUXT_PUBLIC_LEAGUE_ID=sba
+# API endpoints
 NUXT_PUBLIC_API_URL=http://localhost:8000
 NUXT_PUBLIC_WS_URL=http://localhost:8000
+
+# Discord OAuth (public client ID - safe to expose)
 NUXT_PUBLIC_DISCORD_CLIENT_ID=your-client-id
+NUXT_PUBLIC_DISCORD_REDIRECT_URI=http://localhost:3000/auth/callback
+
+# Vite dev server allowed hosts (comma-separated)
+# Add your domain for external access
+NUXT_ALLOWED_HOSTS=localhost,127.0.0.1
 ```
 
+**Note**: `NUXT_ALLOWED_HOSTS` is read in `nuxt.config.ts` to configure Vite's `allowedHosts`. Required when accessing dev server through a reverse proxy or external domain.
+
 ### League Theme
 - Primary: #1e40af (SBA Blue)
 - Secondary: #dc2626 (SBA Red)
diff --git a/frontend-sba/nuxt.config.ts b/frontend-sba/nuxt.config.ts
index 61225fd..6c48db6 100644
--- a/frontend-sba/nuxt.config.ts
+++ b/frontend-sba/nuxt.config.ts
@@ -31,9 +31,10 @@ export default defineNuxtConfig({
   },
 
   // Vite config for external hostname access
+  // Configure NUXT_ALLOWED_HOSTS env var for your domains (comma-separated)
   vite: {
     server: {
-      allowedHosts: ['gameplay-demo.manticorum.com', 'localhost', '127.0.0.1']
+      allowedHosts: process.env.NUXT_ALLOWED_HOSTS?.split(',') || ['localhost', '127.0.0.1']
     }
   },