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+# Build Process Documentation
+
+## Overview
+
+Pokedex.Online uses a multi-stage build process for frontend and backend components.
+
+## Prerequisites
+
+- Node.js 20+ (LTS)
+- npm 10+
+- Docker & Docker Compose (for containerized builds)
+
+## Build Scripts
+
+### Frontend Build
+
+```bash
+# Build frontend only
+npm run build:frontend
+
+# Output: dist/ directory with optimized Vue.js app
+```
+
+**What it does:**
+- Compiles Vue 3 components
+- Bundles JavaScript with Vite (uses Rollup)
+- Minifies with Terser
+- Generates source maps
+- Splits vendor chunks for better caching
+- Optimizes CSS with code splitting
+- Processes assets (images, fonts)
+
+**Build Optimizations:**
+- **Code Splitting**: Separate chunks for Vue, Highlight.js, Virtual Scroller
+- **Tree Shaking**: Removes unused code
+- **Minification**: Reduces bundle size
+- **Source Maps**: Enables production debugging
+- **Asset Optimization**: Inlines small assets, optimizes images
+
+### Backend Build
+
+```bash
+# Build backend (validation only - Node.js doesn't need compilation)
+npm run build:backend
+```
+
+**What it does:**
+- Validates environment configuration
+- Checks dependencies are installed
+- No actual compilation (Node.js runs directly)
+
+### Full Build
+
+```bash
+# Build both frontend and backend
+npm run build
+
+# Then verify the build
+npm run build:verify
+```
+
+### Build Verification
+
+```bash
+npm run build:verify
+```
+
+**Checks:**
+- ✅ dist/ directory exists
+- ✅ index.html present
+- ✅ JavaScript bundles created
+- ✅ CSS files generated
+- ✅ Assets directory populated
+- ⚠️  Warns on large bundles (>1MB)
+- 📊 Shows total build size
+
+## Build Output
+
+### Frontend (`dist/`)
+
+```
+dist/
+├── index.html              # Entry point
+├── assets/
+│   ├── vue-vendor.*.js    # Vue + Vue Router chunk
+│   ├── highlight.*.js     # Highlight.js chunk
+│   ├── virtual-scroller.*.js  # Virtual Scroller chunk
+│   ├── index.*.js         # Main app bundle
+│   ├── index.*.css        # Compiled styles
+│   └── *.{png,svg,ico}    # Optimized assets
+└── vite.svg               # App icon
+```
+
+**Expected Sizes:**
+- Total: 2-3 MB (uncompressed)
+- vue-vendor chunk: ~500 KB
+- Main bundle: ~300-500 KB
+- Highlight.js: ~200-400 KB
+- CSS: ~50-100 KB
+
+### Backend (No build output)
+
+Backend runs directly from source in production container.
+
+## Docker Build
+
+### Build Production Images
+
+```bash
+# Build both containers
+npm run docker:build
+
+# Or manually
+docker compose -f docker-compose.production.yml build
+```
+
+**Images created:**
+- `pokedex-frontend`: Nginx + built static files
+- `pokedex-backend`: Node.js + Express server
+
+### Frontend Dockerfile (`Dockerfile.frontend`)
+
+```dockerfile
+FROM nginx:alpine
+COPY dist /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 80 443
+```
+
+### Backend Dockerfile (`server/Dockerfile`)
+
+```dockerfile
+FROM node:20-alpine
+WORKDIR /app
+COPY package*.json ./
+RUN npm ci --only=production
+COPY . .
+EXPOSE 3000
+CMD ["node", "oauth-proxy.js"]
+```
+
+## Development vs Production
+
+### Development Build
+
+```bash
+npm run dev        # Hot reload, no optimization
+npm run dev:full   # Frontend + Backend with hot reload
+```
+
+**Features:**
+- Hot Module Replacement (HMR)
+- Fast rebuilds
+- Detailed error messages
+- No minification
+- Source maps enabled
+
+### Production Build
+
+```bash
+npm run build           # Full optimization
+npm run build:verify    # Validate build
+```
+
+**Features:**
+- Minified code
+- Tree shaking
+- Code splitting
+- Asset optimization
+- Production source maps
+- Vendor chunk splitting
+
+## Build Configuration
+
+### Vite Config (`vite.config.js`)
+
+```javascript
+build: {
+  target: 'es2015',           // Browser compatibility
+  minify: 'terser',           // Minifier
+  sourcemap: true,            // Source maps
+  rollupOptions: {
+    output: {
+      manualChunks: {         // Chunk splitting
+        'vue-vendor': ['vue', 'vue-router'],
+        'highlight': ['highlight.js'],
+        'virtual-scroller': ['vue-virtual-scroller']
+      }
+    }
+  },
+  chunkSizeWarningLimit: 600, // 600KB warning limit
+  cssCodeSplit: true,         // Split CSS per chunk
+  assetsInlineLimit: 10240    // Inline <10KB assets
+}
+```
+
+## Troubleshooting
+
+### Build Fails
+
+```bash
+# Clean and rebuild
+rm -rf dist node_modules
+npm install
+npm run build
+```
+
+### Build Verification Fails
+
+**Missing index.html:**
+- Check Vite config
+- Verify `index.html` exists in project root
+
+**No JavaScript bundles:**
+- Check for build errors
+- Verify Vue plugin is configured
+
+**Large bundle warnings:**
+- Review `manualChunks` configuration
+- Consider lazy loading components
+- Check for unnecessary dependencies
+
+### Out of Memory
+
+```bash
+# Increase Node.js memory
+NODE_OPTIONS="--max-old-space-size=4096" npm run build
+```
+
+### Slow Builds
+
+**Solutions:**
+- Enable Vite cache
+- Reduce bundle size with lazy loading
+- Use faster disk (SSD)
+- Upgrade Node.js version
+
+## Performance Tips
+
+1. **Lazy Load Routes**: Split Vue Router routes into separate chunks
+2. **Optimize Images**: Use WebP format, compress before build
+3. **Tree Shaking**: Ensure imports are ES modules
+4. **Bundle Analysis**: Use `rollup-plugin-visualizer`
+5. **CDN Assets**: Consider CDN for large vendor libraries
+
+## CI/CD Integration
+
+```yaml
+# Example GitHub Actions
+- name: Install dependencies
+  run: npm ci
+  
+- name: Run tests
+  run: npm run test:run
+  
+- name: Build frontend
+  run: npm run build:frontend
+  
+- name: Verify build
+  run: npm run build:verify
+  
+- name: Build Docker images
+  run: npm run docker:build
+```
+
+## Environment Variables
+
+### Build-time Variables
+
+No build-time environment variables required for frontend.
+
+### Runtime Variables (Backend)
+
+See `server/.env.example` for required variables:
+- `NODE_ENV`
+- `PORT`
+- `CHALLONGE_CLIENT_ID`
+- `CHALLONGE_CLIENT_SECRET`
+- `SESSION_SECRET`
+
+## Next Steps
+
+After successful build:
+
+1. **Local Testing**: `npm run docker:up`
+2. **Deployment**: `npm run deploy:internal` or `npm run deploy:external`
+3. **Monitoring**: Check logs with `npm run docker:logs`