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+# RFCP Phase 2.1: Desktop Application (Windows, Linux, macOS)
+
+**Date:** January 31, 2025  
+**Type:** Packaging & Distribution  
+**Estimated:** 16-20 hours  
+**Priority:** HIGH — main product delivery
+
+---
+
+## 🎯 Goal
+
+Package RFCP as standalone desktop application for Windows, Linux, and macOS. Fully offline after initial region download. No VPS, no MongoDB, no internet required.
+
+---
+
+## 📊 Target Specs
+
+| Metric | Target |
+|--------|--------|
+| Installer size | 200-300 MB |
+| Installed size | 500MB - 1GB (without map data) |
+| With Ukraine region | ~3.5 GB |
+| **Platforms** | **Windows 10/11, Ubuntu 22.04+, macOS 12+** |
+| Offline | Full offline after region download |
+| GPU | Optional CUDA acceleration (Win/Linux) |
+
+---
+
+## 🏗️ Architecture
+
+```
+┌─────────────────────────────────────────────────┐
+│              RFCP Desktop App                   │
+├─────────────────────────────────────────────────┤
+│  ┌─────────────────────────────────────────┐    │
+│  │         Electron Shell                  │    │
+│  │    (Chromium + Node.js runtime)         │    │
+│  └──────────────────┬──────────────────────┘    │
+│                     │                           │
+│  ┌──────────────────▼──────────────────────┐    │
+│  │       React Frontend (bundled)          │    │
+│  └──────────────────┬──────────────────────┘    │
+│                     │ http://localhost:8888     │
+│  ┌──────────────────▼──────────────────────┐    │
+│  │    FastAPI Backend (PyInstaller exe)    │    │
+│  │    ┌────────────────────────────────┐   │    │
+│  │    │  Propagation Engine            │   │    │
+│  │    │  ├── CPU (NumPy/SciPy)         │   │    │
+│  │    │  └── GPU (CuPy) [optional]     │   │    │
+│  │    └────────────────────────────────┘   │    │
+│  └──────────────────┬──────────────────────┘    │
+│                     │                           │
+│  ┌──────────────────▼──────────────────────┐    │
+│  │         Local Data Store                │    │
+│  │  ├── SQLite (projects, settings)        │    │
+│  │  ├── SRTM tiles (~25MB each)            │    │
+│  │  ├── OSM cache (buildings, water, veg)  │    │
+│  │  └── Map tiles (optional offline maps)  │    │
+│  └─────────────────────────────────────────┘    │
+└─────────────────────────────────────────────────┘
+```
+
+---
+
+## 📁 Project Structure
+
+```
+rfcp/
+├── frontend/                 # React (existing)
+├── backend/                  # FastAPI (existing)
+├── desktop/                  # NEW — Electron app
+│   ├── main.js               # Electron main process
+│   ├── preload.js            # Context bridge
+│   ├── splash.html           # Loading screen
+│   ├── package.json          # Electron deps + build config
+│   └── assets/
+│       ├── icon.ico          # Windows icon (256x256)
+│       ├── icon.png          # Linux icon (512x512)
+│       └── icon.icns         # macOS icon
+├── installer/                # NEW — Build scripts
+│   ├── build-win.sh          # Windows build script
+│   ├── build-linux.sh        # Linux build script
+│   ├── build-mac.sh          # macOS build script
+│   ├── build-all.sh          # Build all platforms
+│   └── rfcp-server.spec      # PyInstaller spec
+├── docs/
+├── scripts/
+└── CLAUDE.md
+```
+
+---
+
+## 📁 Installed Directory Structure
+
+### Windows
+```
+C:\Program Files\RFCP\
+├── RFCP.exe                 # Electron app
+├── resources/
+│   ├── app.asar             # Frontend bundle
+│   └── backend/
+│       └── rfcp-server.exe  # PyInstaller bundle
+└── Uninstall RFCP.exe
+
+%APPDATA%\RFCP\              # User data
+├── rfcp.db                  # SQLite database
+├── terrain/                 # SRTM tiles
+├── osm/                     # OSM cache
+└── projects/                # User projects
+```
+
+### Linux
+```
+/opt/RFCP/                   # AppImage extracts here
+├── rfcp                     # Main binary
+└── resources/
+    └── ...
+
+~/.local/share/RFCP/         # User data
+├── rfcp.db
+├── terrain/
+├── osm/
+└── projects/
+```
+
+### macOS
+```
+/Applications/RFCP.app/      # App bundle
+└── Contents/
+    ├── MacOS/rfcp           # Main binary
+    ├── Resources/
+    │   ├── backend/
+    │   └── frontend/
+    └── Info.plist
+
+~/Library/Application Support/RFCP/  # User data
+├── rfcp.db
+├── terrain/
+├── osm/
+└── projects/
+```
+
+---
+
+## ✅ Tasks
+
+### Task 2.1.1: Project Setup (1-2 hours)
+
+**Create `desktop/package.json`:**
+```json
+{
+  "name": "rfcp-desktop",
+  "version": "1.6.1",
+  "description": "RF Coverage Planner - Tactical Communications",
+  "main": "main.js",
+  "author": "UMTC Project",
+  "license": "MIT",
+  "scripts": {
+    "start": "electron .",
+    "dev": "NODE_ENV=development electron .",
+    "build": "electron-builder",
+    "build:win": "electron-builder --win",
+    "build:linux": "electron-builder --linux",
+    "build:mac": "electron-builder --mac",
+    "build:all": "electron-builder --win --linux --mac"
+  },
+  "dependencies": {
+    "electron-store": "^8.1.0"
+  },
+  "devDependencies": {
+    "electron": "^28.0.0",
+    "electron-builder": "^24.9.0"
+  },
+  "build": {
+    "appId": "one.eliah.rfcp",
+    "productName": "RFCP",
+    "copyright": "Copyright © 2025 UMTC Project",
+    "directories": {
+      "output": "dist",
+      "buildResources": "assets"
+    },
+    "files": [
+      "main.js",
+      "preload.js",
+      "splash.html"
+    ],
+    "extraResources": [
+      {
+        "from": "../frontend/dist",
+        "to": "frontend"
+      },
+      {
+        "from": "./backend-dist/${os}",
+        "to": "backend"
+      }
+    ],
+    "win": {
+      "target": ["nsis"],
+      "icon": "assets/icon.ico"
+    },
+    "nsis": {
+      "oneClick": false,
+      "allowToChangeInstallationDirectory": true,
+      "createDesktopShortcut": true,
+      "createStartMenuShortcut": true,
+      "shortcutName": "RFCP"
+    },
+    "linux": {
+      "target": ["AppImage", "deb"],
+      "icon": "assets/icon.png",
+      "category": "Science"
+    },
+    "mac": {
+      "target": ["dmg", "zip"],
+      "icon": "assets/icon.icns",
+      "category": "public.app-category.developer-tools",
+      "hardenedRuntime": false,
+      "gatekeeperAssess": false
+    },
+    "dmg": {
+      "title": "RFCP Installer",
+      "backgroundColor": "#1a1a2e",
+      "contents": [
+        { "x": 130, "y": 220 },
+        { "x": 410, "y": 220, "type": "link", "path": "/Applications" }
+      ]
+    }
+  }
+}
+```
+
+---
+
+### Task 2.1.2: Electron Main Process (3-4 hours)
+
+**desktop/main.js:**
+```javascript
+const { app, BrowserWindow, ipcMain, dialog, shell } = require('electron');
+const { spawn, execSync } = require('child_process');
+const path = require('path');
+const fs = require('fs');
+const Store = require('electron-store');
+
+const store = new Store();
+let mainWindow;
+let splashWindow;
+let backendProcess;
+
+// Paths
+const isDev = process.env.NODE_ENV === 'development';
+
+const getResourcePath = (relativePath) => {
+  if (isDev) {
+    return path.join(__dirname, '..', relativePath);
+  }
+  return path.join(process.resourcesPath, relativePath);
+};
+
+const getDataPath = () => {
+  return path.join(app.getPath('userData'), 'data');
+};
+
+// Get backend executable name based on platform
+const getBackendExeName = () => {
+  switch (process.platform) {
+    case 'win32':
+      return 'rfcp-server.exe';
+    case 'darwin':
+      return 'rfcp-server';
+    case 'linux':
+      return 'rfcp-server';
+    default:
+      return 'rfcp-server';
+  }
+};
+
+// Ensure data directories exist
+function ensureDataDirs() {
+  const dirs = ['terrain', 'osm', 'projects', 'cache'];
+  const dataPath = getDataPath();
+  
+  dirs.forEach(dir => {
+    const fullPath = path.join(dataPath, dir);
+    if (!fs.existsSync(fullPath)) {
+      fs.mkdirSync(fullPath, { recursive: true });
+    }
+  });
+  
+  return dataPath;
+}
+
+// Create splash window
+function createSplashWindow() {
+  splashWindow = new BrowserWindow({
+    width: 400,
+    height: 300,
+    frame: false,
+    transparent: true,
+    alwaysOnTop: true,
+    resizable: false,
+    webPreferences: {
+      nodeIntegration: true,
+      contextIsolation: false
+    }
+  });
+  
+  splashWindow.loadFile(path.join(__dirname, 'splash.html'));
+  splashWindow.center();
+}
+
+// Start Python backend
+async function startBackend() {
+  const dataPath = ensureDataDirs();
+  
+  const env = {
+    ...process.env,
+    RFCP_DATA_PATH: dataPath,
+    RFCP_DATABASE_URL: `sqlite:///${path.join(dataPath, 'rfcp.db')}`,
+    RFCP_HOST: '127.0.0.1',
+    RFCP_PORT: '8888',
+  };
+
+  if (isDev) {
+    // Development: run uvicorn
+    const pythonCmd = process.platform === 'win32' ? 'python' : 'python3';
+    backendProcess = spawn(pythonCmd, [
+      '-m', 'uvicorn', 
+      'app.main:app', 
+      '--host', '127.0.0.1',
+      '--port', '8888',
+      '--reload'
+    ], {
+      cwd: path.join(__dirname, '..', 'backend'),
+      env,
+      stdio: ['ignore', 'pipe', 'pipe']
+    });
+  } else {
+    // Production: run PyInstaller bundle
+    const backendExe = path.join(
+      getResourcePath('backend'),
+      getBackendExeName()
+    );
+    
+    // Make executable on Unix
+    if (process.platform !== 'win32') {
+      try {
+        fs.chmodSync(backendExe, '755');
+      } catch (e) {
+        console.log('chmod failed:', e);
+      }
+    }
+    
+    backendProcess = spawn(backendExe, [], {
+      env,
+      stdio: ['ignore', 'pipe', 'pipe']
+    });
+  }
+
+  // Log backend output
+  backendProcess.stdout?.on('data', (data) => {
+    console.log(`[Backend] ${data}`);
+  });
+
+  backendProcess.stderr?.on('data', (data) => {
+    console.error(`[Backend Error] ${data}`);
+  });
+
+  backendProcess.on('error', (err) => {
+    console.error('Failed to start backend:', err);
+    dialog.showErrorBox('Backend Error', `Failed to start backend: ${err.message}`);
+  });
+
+  // Wait for backend to be ready
+  return new Promise((resolve) => {
+    const maxAttempts = 60;  // 30 seconds
+    let attempts = 0;
+    
+    const checkBackend = setInterval(async () => {
+      attempts++;
+      
+      try {
+        const response = await fetch('http://127.0.0.1:8888/api/health/');
+        if (response.ok) {
+          clearInterval(checkBackend);
+          console.log('Backend ready!');
+          resolve(true);
+        }
+      } catch (e) {
+        // Not ready yet
+      }
+      
+      if (attempts >= maxAttempts) {
+        clearInterval(checkBackend);
+        console.error('Backend failed to start in time');
+        resolve(false);
+      }
+    }, 500);
+  });
+}
+
+// Create main window
+function createMainWindow() {
+  const windowState = store.get('windowState', {
+    width: 1400,
+    height: 900
+  });
+
+  mainWindow = new BrowserWindow({
+    width: windowState.width,
+    height: windowState.height,
+    x: windowState.x,
+    y: windowState.y,
+    minWidth: 1024,
+    minHeight: 768,
+    show: false,
+    webPreferences: {
+      nodeIntegration: false,
+      contextIsolation: true,
+      preload: path.join(__dirname, 'preload.js')
+    },
+    icon: path.join(__dirname, 'assets', 
+      process.platform === 'win32' ? 'icon.ico' : 'icon.png'
+    ),
+    title: 'RFCP - RF Coverage Planner',
+    titleBarStyle: process.platform === 'darwin' ? 'hiddenInset' : 'default',
+  });
+
+  // Save window state on close
+  mainWindow.on('close', () => {
+    const bounds = mainWindow.getBounds();
+    store.set('windowState', bounds);
+  });
+
+  // Load frontend
+  if (isDev) {
+    mainWindow.loadURL('http://localhost:5173');
+    mainWindow.webContents.openDevTools();
+  } else {
+    mainWindow.loadFile(path.join(getResourcePath('frontend'), 'index.html'));
+  }
+
+  mainWindow.once('ready-to-show', () => {
+    if (splashWindow) {
+      splashWindow.close();
+      splashWindow = null;
+    }
+    mainWindow.show();
+  });
+
+  mainWindow.on('closed', () => {
+    mainWindow = null;
+  });
+
+  // Handle external links
+  mainWindow.webContents.setWindowOpenHandler(({ url }) => {
+    shell.openExternal(url);
+    return { action: 'deny' };
+  });
+}
+
+// App lifecycle
+app.whenReady().then(async () => {
+  createSplashWindow();
+  
+  const backendStarted = await startBackend();
+  
+  if (!backendStarted) {
+    const result = await dialog.showMessageBox({
+      type: 'error',
+      title: 'Startup Error',
+      message: 'Failed to start backend server.',
+      detail: 'Please check logs and try again. Click "Show Logs" to open the log folder.',
+      buttons: ['Quit', 'Show Logs']
+    });
+    
+    if (result.response === 1) {
+      shell.openPath(app.getPath('logs'));
+    }
+    
+    app.quit();
+    return;
+  }
+  
+  createMainWindow();
+});
+
+app.on('window-all-closed', () => {
+  if (backendProcess) {
+    backendProcess.kill();
+    backendProcess = null;
+  }
+  
+  if (process.platform !== 'darwin') {
+    app.quit();
+  }
+});
+
+app.on('activate', () => {
+  if (mainWindow === null) {
+    createMainWindow();
+  }
+});
+
+app.on('before-quit', () => {
+  if (backendProcess) {
+    backendProcess.kill();
+  }
+});
+
+// IPC Handlers
+ipcMain.handle('get-data-path', () => getDataPath());
+ipcMain.handle('get-app-version', () => app.getVersion());
+ipcMain.handle('get-platform', () => process.platform);
+
+ipcMain.handle('get-gpu-info', async () => {
+  // TODO: Implement GPU detection
+  return {
+    available: false,
+    name: null,
+    cudaVersion: null
+  };
+});
+
+ipcMain.handle('select-directory', async () => {
+  const result = await dialog.showOpenDialog(mainWindow, {
+    properties: ['openDirectory']
+  });
+  return result.filePaths[0] || null;
+});
+
+ipcMain.handle('select-file', async (event, options) => {
+  const result = await dialog.showOpenDialog(mainWindow, {
+    properties: ['openFile'],
+    filters: options?.filters || []
+  });
+  return result.filePaths[0] || null;
+});
+
+ipcMain.handle('save-file', async (event, options) => {
+  const result = await dialog.showSaveDialog(mainWindow, {
+    defaultPath: options?.defaultPath,
+    filters: options?.filters || []
+  });
+  return result.filePath || null;
+});
+
+ipcMain.handle('get-setting', (event, key) => store.get(key));
+ipcMain.handle('set-setting', (event, key, value) => store.set(key, value));
+
+ipcMain.handle('open-external', (event, url) => shell.openExternal(url));
+ipcMain.handle('open-path', (event, path) => shell.openPath(path));
+```
+
+---
+
+### Task 2.1.3: Preload Script (1 hour)
+
+**desktop/preload.js:**
+```javascript
+const { contextBridge, ipcRenderer } = require('electron');
+
+contextBridge.exposeInMainWorld('rfcp', {
+  // System info
+  getDataPath: () => ipcRenderer.invoke('get-data-path'),
+  getAppVersion: () => ipcRenderer.invoke('get-app-version'),
+  getPlatform: () => ipcRenderer.invoke('get-platform'),
+  getGpuInfo: () => ipcRenderer.invoke('get-gpu-info'),
+  
+  // Dialogs
+  selectDirectory: () => ipcRenderer.invoke('select-directory'),
+  selectFile: (options) => ipcRenderer.invoke('select-file', options),
+  saveFile: (options) => ipcRenderer.invoke('save-file', options),
+  
+  // Settings (persistent)
+  getSetting: (key) => ipcRenderer.invoke('get-setting', key),
+  setSetting: (key, value) => ipcRenderer.invoke('set-setting', key, value),
+  
+  // Shell
+  openExternal: (url) => ipcRenderer.invoke('open-external', url),
+  openPath: (path) => ipcRenderer.invoke('open-path', path),
+  
+  // Platform info
+  platform: process.platform,
+  isDesktop: true,
+  isMac: process.platform === 'darwin',
+  isWindows: process.platform === 'win32',
+  isLinux: process.platform === 'linux',
+});
+```
+
+---
+
+### Task 2.1.4: Splash Screen (30 min)
+
+**desktop/splash.html:**
+```html
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="UTF-8">
+  <title>RFCP Loading</title>
+  <style>
+    * { margin: 0; padding: 0; box-sizing: border-box; }
+    
+    body {
+      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+      background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
+      color: white;
+      height: 100vh;
+      display: flex;
+      flex-direction: column;
+      align-items: center;
+      justify-content: center;
+      -webkit-app-region: drag;
+      user-select: none;
+      border-radius: 12px;
+    }
+    
+    .logo {
+      font-size: 48px;
+      font-weight: bold;
+      margin-bottom: 8px;
+      background: linear-gradient(90deg, #00d4ff, #00ff88);
+      -webkit-background-clip: text;
+      -webkit-text-fill-color: transparent;
+    }
+    
+    .subtitle {
+      font-size: 14px;
+      color: #888;
+      margin-bottom: 30px;
+    }
+    
+    .loader {
+      width: 200px;
+      height: 4px;
+      background: #333;
+      border-radius: 2px;
+      overflow: hidden;
+    }
+    
+    .loader-bar {
+      height: 100%;
+      width: 30%;
+      background: linear-gradient(90deg, #00d4ff, #00ff88);
+      border-radius: 2px;
+      animation: loading 1.5s ease-in-out infinite;
+    }
+    
+    @keyframes loading {
+      0% { transform: translateX(-100%); }
+      100% { transform: translateX(400%); }
+    }
+    
+    .status {
+      margin-top: 15px;
+      font-size: 12px;
+      color: #666;
+    }
+    
+    .version {
+      position: absolute;
+      bottom: 15px;
+      font-size: 11px;
+      color: #444;
+    }
+  </style>
+</head>
+<body>
+  <div class="logo">RFCP</div>
+  <div class="subtitle">RF Coverage Planner</div>
+  <div class="loader">
+    <div class="loader-bar"></div>
+  </div>
+  <div class="status">Starting backend server...</div>
+  <div class="version">v1.6.1</div>
+</body>
+</html>
+```
+
+---
+
+### Task 2.1.5: PyInstaller Backend Bundle (3-4 hours)
+
+**backend/run_server.py (new entry point):**
+```python
+"""Entry point for PyInstaller bundle"""
+import os
+import sys
+
+# Set base path for PyInstaller
+if getattr(sys, 'frozen', False):
+    # Running as compiled
+    os.chdir(os.path.dirname(sys.executable))
+
+import uvicorn
+from app.main import app
+
+if __name__ == '__main__':
+    host = os.environ.get('RFCP_HOST', '127.0.0.1')
+    port = int(os.environ.get('RFCP_PORT', '8888'))
+    
+    uvicorn.run(
+        app,
+        host=host,
+        port=port,
+        log_level='info',
+    )
+```
+
+**installer/rfcp-server.spec:**
+```python
+# -*- mode: python ; coding: utf-8 -*-
+import sys
+from pathlib import Path
+
+block_cipher = None
+backend_path = Path('../backend')
+
+a = Analysis(
+    [str(backend_path / 'run_server.py')],
+    pathex=[str(backend_path)],
+    binaries=[],
+    datas=[
+        (str(backend_path / 'app'), 'app'),
+    ],
+    hiddenimports=[
+        'uvicorn.logging',
+        'uvicorn.protocols.http',
+        'uvicorn.protocols.http.auto',
+        'uvicorn.protocols.http.h11_impl',
+        'uvicorn.protocols.websockets',
+        'uvicorn.protocols.websockets.auto',
+        'uvicorn.lifespan',
+        'uvicorn.lifespan.on',
+        'uvicorn.lifespan.off',
+        'httpx',
+        'h11',
+        'numpy',
+        'scipy',
+        'scipy.special',
+        'scipy.interpolate',
+        'aiosqlite',
+        'sqlalchemy',
+        'sqlalchemy.dialects.sqlite',
+    ],
+    hookspath=[],
+    hooksconfig={},
+    runtime_hooks=[],
+    excludes=['tkinter', 'matplotlib', 'PIL', 'pandas', 'IPython'],
+    win_no_prefer_redirects=False,
+    win_private_assemblies=False,
+    cipher=block_cipher,
+    noarchive=False,
+)
+
+pyz = PYZ(a.pure, a.zipped_data, cipher=block_cipher)
+
+exe = EXE(
+    pyz,
+    a.scripts,
+    a.binaries,
+    a.zipfiles,
+    a.datas,
+    [],
+    name='rfcp-server',
+    debug=False,
+    bootloader_ignore_signals=False,
+    strip=False,
+    upx=True,
+    upx_exclude=[],
+    runtime_tmpdir=None,
+    console=False,  # No console window
+    disable_windowed_traceback=False,
+    target_arch=None,
+    codesign_identity=None,
+    entitlements_file=None,
+    icon='../desktop/assets/icon.ico' if sys.platform == 'win32' else None,
+)
+```
+
+---
+
+### Task 2.1.6: Build Scripts (2-3 hours)
+
+**installer/build-win.sh:**
+```bash
+#!/bin/bash
+set -e
+
+echo "========================================="
+echo "  RFCP Desktop Build (Windows)"
+echo "========================================="
+
+cd "$(dirname "$0")/.."
+
+# 1. Build frontend
+echo "[1/4] Building frontend..."
+cd frontend
+npm ci
+npm run build
+cd ..
+
+# 2. Build backend with PyInstaller
+echo "[2/4] Building backend..."
+cd backend
+python -m pip install -r requirements.txt
+python -m pip install pyinstaller
+cd ../installer
+python -m PyInstaller rfcp-server.spec --clean --noconfirm
+mkdir -p ../desktop/backend-dist/win32
+cp dist/rfcp-server.exe ../desktop/backend-dist/win32/
+cd ..
+
+# 3. Build Electron app
+echo "[3/4] Building Electron app..."
+cd desktop
+npm ci
+npm run build:win
+cd ..
+
+# 4. Done
+echo "[4/4] Build complete!"
+echo ""
+echo "Output: desktop/dist/"
+ls -la desktop/dist/*.exe 2>/dev/null || echo "Build artifacts in desktop/dist/"
+```
+
+**installer/build-linux.sh:**
+```bash
+#!/bin/bash
+set -e
+
+echo "========================================="
+echo "  RFCP Desktop Build (Linux)"
+echo "========================================="
+
+cd "$(dirname "$0")/.."
+
+# 1. Build frontend
+echo "[1/4] Building frontend..."
+cd frontend
+npm ci
+npm run build
+cd ..
+
+# 2. Build backend with PyInstaller
+echo "[2/4] Building backend..."
+cd backend
+python3 -m pip install -r requirements.txt
+python3 -m pip install pyinstaller
+cd ../installer
+python3 -m PyInstaller rfcp-server.spec --clean --noconfirm
+mkdir -p ../desktop/backend-dist/linux
+cp dist/rfcp-server ../desktop/backend-dist/linux/
+cd ..
+
+# 3. Build Electron app
+echo "[3/4] Building Electron app..."
+cd desktop
+npm ci
+npm run build:linux
+cd ..
+
+# 4. Done
+echo "[4/4] Build complete!"
+ls -la desktop/dist/*.AppImage 2>/dev/null || echo "AppImage in desktop/dist/"
+ls -la desktop/dist/*.deb 2>/dev/null || echo "Deb in desktop/dist/"
+```
+
+**installer/build-mac.sh:**
+```bash
+#!/bin/bash
+set -e
+
+echo "========================================="
+echo "  RFCP Desktop Build (macOS)"
+echo "========================================="
+
+cd "$(dirname "$0")/.."
+
+# Check if running on macOS
+if [[ "$(uname)" != "Darwin" ]]; then
+    echo "Error: This script must run on macOS"
+    exit 1
+fi
+
+# 1. Build frontend
+echo "[1/4] Building frontend..."
+cd frontend
+npm ci
+npm run build
+cd ..
+
+# 2. Build backend with PyInstaller
+echo "[2/4] Building backend..."
+cd backend
+python3 -m pip install -r requirements.txt
+python3 -m pip install pyinstaller
+cd ../installer
+python3 -m PyInstaller rfcp-server.spec --clean --noconfirm
+mkdir -p ../desktop/backend-dist/darwin
+cp dist/rfcp-server ../desktop/backend-dist/darwin/
+cd ..
+
+# 3. Create .icns icon if not exists
+if [ ! -f desktop/assets/icon.icns ]; then
+    echo "Creating macOS icon..."
+    mkdir -p icon.iconset
+    sips -z 16 16     desktop/assets/icon.png --out icon.iconset/icon_16x16.png
+    sips -z 32 32     desktop/assets/icon.png --out icon.iconset/icon_16x16@2x.png
+    sips -z 32 32     desktop/assets/icon.png --out icon.iconset/icon_32x32.png
+    sips -z 64 64     desktop/assets/icon.png --out icon.iconset/icon_32x32@2x.png
+    sips -z 128 128   desktop/assets/icon.png --out icon.iconset/icon_128x128.png
+    sips -z 256 256   desktop/assets/icon.png --out icon.iconset/icon_128x128@2x.png
+    sips -z 256 256   desktop/assets/icon.png --out icon.iconset/icon_256x256.png
+    sips -z 512 512   desktop/assets/icon.png --out icon.iconset/icon_256x256@2x.png
+    sips -z 512 512   desktop/assets/icon.png --out icon.iconset/icon_512x512.png
+    sips -z 1024 1024 desktop/assets/icon.png --out icon.iconset/icon_512x512@2x.png
+    iconutil -c icns icon.iconset -o desktop/assets/icon.icns
+    rm -rf icon.iconset
+fi
+
+# 4. Build Electron app
+echo "[3/4] Building Electron app..."
+cd desktop
+npm ci
+npm run build:mac
+cd ..
+
+# 5. Done
+echo "[4/4] Build complete!"
+ls -la desktop/dist/*.dmg 2>/dev/null || echo "DMG in desktop/dist/"
+```
+
+---
+
+### Task 2.1.7: Frontend Desktop Detection (1 hour)
+
+**frontend/src/lib/desktop.ts:**
+```typescript
+interface RFCPDesktop {
+  getDataPath: () => Promise<string>;
+  getAppVersion: () => Promise<string>;
+  getPlatform: () => Promise<string>;
+  getGpuInfo: () => Promise<{
+    available: boolean;
+    name: string | null;
+    cudaVersion: string | null;
+  }>;
+  selectDirectory: () => Promise<string | null>;
+  selectFile: (options?: { filters?: Array<{ name: string; extensions: string[] }> }) => Promise<string | null>;
+  saveFile: (options?: { defaultPath?: string; filters?: Array<{ name: string; extensions: string[] }> }) => Promise<string | null>;
+  getSetting: (key: string) => Promise<any>;
+  setSetting: (key: string, value: any) => Promise<void>;
+  openExternal: (url: string) => Promise<void>;
+  openPath: (path: string) => Promise<void>;
+  platform: string;
+  isDesktop: boolean;
+  isMac: boolean;
+  isWindows: boolean;
+  isLinux: boolean;
+}
+
+declare global {
+  interface Window {
+    rfcp?: RFCPDesktop;
+  }
+}
+
+export const isDesktop = (): boolean => {
+  return window.rfcp?.isDesktop === true;
+};
+
+export const getDesktopApi = (): RFCPDesktop | null => {
+  return window.rfcp || null;
+};
+
+export const getApiBaseUrl = (): string => {
+  if (isDesktop()) {
+    return 'http://127.0.0.1:8888';
+  }
+  return import.meta.env.VITE_API_URL || 'https://api.rfcp.eliah.one';
+};
+
+export const isMac = (): boolean => {
+  return window.rfcp?.isMac === true;
+};
+```
+
+**Update frontend/src/services/api.ts:**
+```typescript
+import { getApiBaseUrl } from '../lib/desktop';
+
+const API_BASE = getApiBaseUrl();
+// ... rest remains same
+```
+
+---
+
+## 🧪 Testing
+
+### Development Testing
+```bash
+# Terminal 1: Backend
+cd backend
+uvicorn app.main:app --host 127.0.0.1 --port 8888 --reload
+
+# Terminal 2: Frontend  
+cd frontend
+npm run dev
+
+# Terminal 3: Electron
+cd desktop
+npm run dev
+```
+
+### Build Testing
+
+**Windows:**
+```bash
+cd installer
+./build-win.sh
+# Test: desktop/dist/RFCP Setup 1.6.1.exe
+```
+
+**Linux:**
+```bash
+cd installer
+./build-linux.sh
+# Test: desktop/dist/RFCP-1.6.1.AppImage
+```
+
+**macOS (run on Mac):**
+```bash
+cd installer
+./build-mac.sh
+# Test: desktop/dist/RFCP-1.6.1.dmg
+```
+
+### Checklist
+- [ ] Installer runs without errors
+- [ ] Backend starts automatically (check splash → main window)
+- [ ] Frontend loads in Electron window
+- [ ] Coverage calculation works
+- [ ] Data persists between sessions (SQLite)
+- [ ] Window state persists (size, position)
+- [ ] File dialogs work (import/export)
+- [ ] External links open in browser
+
+---
+
+## 📦 Deliverables
+
+| Platform | File | Size |
+|----------|------|------|
+| Windows | `RFCP-Setup-1.6.1.exe` | ~250MB |
+| Linux | `RFCP-1.6.1.AppImage` | ~200MB |
+| Linux | `RFCP-1.6.1.deb` | ~200MB |
+| macOS | `RFCP-1.6.1.dmg` | ~220MB |
+| macOS | `RFCP-1.6.1-mac.zip` | ~210MB |
+
+---
+
+## 🔜 Future (2.2+)
+
+- [ ] First-run region download wizard
+- [ ] GPU acceleration toggle in settings  
+- [ ] Auto-updater (electron-updater)
+- [ ] Portable mode (no install, run from USB)
+- [ ] Code signing (Windows/macOS)
+- [ ] Notarization (macOS)
+
+---
+
+## 📝 Notes
+
+- **macOS signing:** Without Apple Developer account ($99/yr), users see "unverified developer" warning. They can bypass via System Preferences → Security.
+- **SQLite** replaces MongoDB — simpler, no server needed
+- **SRTM tiles** ~25MB each, Ukraine needs ~120 tiles = ~3GB
+- **Icons:** Need 512x512 PNG source, scripts generate .ico and .icns
+
+---
+
+**Ready for Claude Code** 🚀
diff --git a/RFCP-Phase-2.1-Desktop-Installer.md b/RFCP-Phase-2.1-Desktop-Installer.md
deleted file mode 100644
index 2f9f546..0000000
--- a/RFCP-Phase-2.1-Desktop-Installer.md
+++ /dev/null
@@ -1,730 +0,0 @@
-# RFCP Phase 2.1: Desktop Application & Installer
-
-**Date:** January 31, 2025  
-**Type:** Packaging & Distribution  
-**Estimated:** 20-30 hours  
-**Priority:** After frontend-backend integration (1.5)
-
----
-
-## 🎯 Goal
-
-Package RFCP as standalone desktop application with installer for Windows and Linux. Fully offline capable after initial setup.
-
----
-
-## 📊 Target Specs
-
-| Metric | Target |
-|--------|--------|
-| Installer size | 200-300 MB |
-| Installed size | 500MB - 1GB |
-| Platforms | Windows 10/11, Ubuntu 22.04+ |
-| Offline | Full offline after region download |
-| GPU | Optional, configurable in settings |
-
----
-
-## 🏗️ Architecture
-
-```
-┌─────────────────────────────────────────────┐
-│              RFCP Desktop App               │
-├─────────────────────────────────────────────┤
-│  ┌─────────────────────────────────────┐    │
-│  │         Electron Shell              │    │
-│  │  (Chromium + Node.js runtime)       │    │
-│  └──────────────┬──────────────────────┘    │
-│                 │                           │
-│  ┌──────────────▼──────────────────────┐    │
-│  │       React Frontend (UI)           │    │
-│  │   localhost:5173 (dev) / bundled    │    │
-│  └──────────────┬──────────────────────┘    │
-│                 │ HTTP API                  │
-│  ┌──────────────▼──────────────────────┐    │
-│  │    FastAPI Backend (Python)         │    │
-│  │       localhost:8888                │    │
-│  │  ┌────────────────────────────┐     │    │
-│  │  │  Propagation Engine        │     │    │
-│  │  │  ├── CPU (default)         │     │    │
-│  │  │  └── GPU (optional/CUDA)   │     │    │
-│  │  └────────────────────────────┘     │    │
-│  └──────────────┬──────────────────────┘    │
-│                 │                           │
-│  ┌──────────────▼──────────────────────┐    │
-│  │         Local Data Store            │    │
-│  │  ├── SQLite (projects, settings)    │    │
-│  │  ├── SRTM tiles (elevation)         │    │
-│  │  └── OSM cache (buildings, roads)   │    │
-│  └─────────────────────────────────────┘    │
-└─────────────────────────────────────────────┘
-```
-
----
-
-## 📁 Directory Structure
-
-### Development
-```
-rfcp/
-├── electron/
-│   ├── main.js              # Electron main process
-│   ├── preload.js           # Context bridge
-│   ├── package.json         # Electron deps
-│   └── build/               # electron-builder config
-│       ├── icon.ico
-│       ├── icon.png
-│       └── installer.nsh    # NSIS customization
-├── frontend/                # React (existing)
-├── backend/                 # FastAPI (existing)
-└── scripts/
-    ├── build-windows.sh
-    ├── build-linux.sh
-    └── package-python.sh
-```
-
-### Installed (Windows)
-```
-C:\Program Files\RFCP\
-├── RFCP.exe                 # Electron app
-├── resources/
-│   ├── app.asar             # Frontend bundle
-│   └── backend/
-│       ├── rfcp-server.exe  # PyInstaller bundle
-│       └── app/             # Python code
-├── data/
-│   ├── rfcp.db              # SQLite database
-│   ├── srtm/                # Elevation tiles
-│   ├── osm/                 # OSM cache
-│   └── projects/            # User projects
-├── python/                  # Embedded Python (if not PyInstaller)
-└── Uninstall RFCP.exe
-```
-
-### Installed (Linux)
-```
-/opt/rfcp/
-├── rfcp                     # AppImage or binary
-├── resources/
-│   └── ...
-└── data/
-    └── ...
-
-~/.local/share/rfcp/         # User data
-├── rfcp.db
-├── srtm/
-├── osm/
-└── projects/
-```
-
----
-
-## ✅ Tasks
-
-### Task 2.1.1: Electron Shell (4-6 hours)
-
-**electron/main.js:**
-```javascript
-const { app, BrowserWindow, ipcMain } = require('electron');
-const { spawn } = require('child_process');
-const path = require('path');
-const fs = require('fs');
-
-let mainWindow;
-let backendProcess;
-
-// Paths
-const isDev = process.env.NODE_ENV === 'development';
-const backendPath = isDev 
-    ? path.join(__dirname, '../backend')
-    : path.join(process.resourcesPath, 'backend');
-
-const dataPath = isDev
-    ? path.join(__dirname, '../data')
-    : path.join(app.getPath('userData'), 'data');
-
-// Ensure data directories exist
-function ensureDataDirs() {
-    const dirs = ['srtm', 'osm', 'projects'];
-    dirs.forEach(dir => {
-        const fullPath = path.join(dataPath, dir);
-        if (!fs.existsSync(fullPath)) {
-            fs.mkdirSync(fullPath, { recursive: true });
-        }
-    });
-}
-
-// Start Python backend
-function startBackend() {
-    const pythonExe = isDev 
-        ? 'python'
-        : path.join(process.resourcesPath, 'backend', 'rfcp-server.exe');
-    
-    const env = {
-        ...process.env,
-        RFCP_DATA_PATH: dataPath,
-        RFCP_PORT: '8888'
-    };
-
-    if (isDev) {
-        backendProcess = spawn(pythonExe, ['-m', 'uvicorn', 'app.main:app', '--port', '8888'], {
-            cwd: backendPath,
-            env
-        });
-    } else {
-        backendProcess = spawn(pythonExe, [], { env });
-    }
-
-    backendProcess.stdout.on('data', (data) => {
-        console.log(`Backend: ${data}`);
-    });
-
-    backendProcess.stderr.on('data', (data) => {
-        console.error(`Backend Error: ${data}`);
-    });
-
-    return new Promise((resolve) => {
-        // Wait for backend to be ready
-        const checkBackend = setInterval(async () => {
-            try {
-                const response = await fetch('http://localhost:8888/api/health/');
-                if (response.ok) {
-                    clearInterval(checkBackend);
-                    resolve();
-                }
-            } catch (e) {
-                // Not ready yet
-            }
-        }, 500);
-
-        // Timeout after 30s
-        setTimeout(() => {
-            clearInterval(checkBackend);
-            resolve(); // Continue anyway
-        }, 30000);
-    });
-}
-
-// Create window
-async function createWindow() {
-    ensureDataDirs();
-    
-    // Show splash while loading
-    const splash = new BrowserWindow({
-        width: 400,
-        height: 300,
-        frame: false,
-        alwaysOnTop: true,
-        transparent: true
-    });
-    splash.loadFile('splash.html');
-
-    // Start backend
-    await startBackend();
-
-    // Create main window
-    mainWindow = new BrowserWindow({
-        width: 1400,
-        height: 900,
-        minWidth: 1024,
-        minHeight: 768,
-        webPreferences: {
-            nodeIntegration: false,
-            contextIsolation: true,
-            preload: path.join(__dirname, 'preload.js')
-        },
-        icon: path.join(__dirname, 'build/icon.png'),
-        title: 'RFCP - RF Coverage Planner'
-    });
-
-    // Load frontend
-    if (isDev) {
-        mainWindow.loadURL('http://localhost:5173');
-        mainWindow.webContents.openDevTools();
-    } else {
-        mainWindow.loadFile(path.join(process.resourcesPath, 'frontend', 'index.html'));
-    }
-
-    // Close splash
-    splash.close();
-
-    mainWindow.on('closed', () => {
-        mainWindow = null;
-    });
-}
-
-// App lifecycle
-app.whenReady().then(createWindow);
-
-app.on('window-all-closed', () => {
-    if (backendProcess) {
-        backendProcess.kill();
-    }
-    if (process.platform !== 'darwin') {
-        app.quit();
-    }
-});
-
-app.on('activate', () => {
-    if (mainWindow === null) {
-        createWindow();
-    }
-});
-
-// IPC handlers
-ipcMain.handle('get-data-path', () => dataPath);
-ipcMain.handle('get-gpu-info', () => {
-    // Detect GPU availability
-    // Could use node-gpu or check CUDA
-    return {
-        available: false, // TODO: implement detection
-        name: null
-    };
-});
-```
-
-**electron/preload.js:**
-```javascript
-const { contextBridge, ipcRenderer } = require('electron');
-
-contextBridge.exposeInMainWorld('rfcp', {
-    getDataPath: () => ipcRenderer.invoke('get-data-path'),
-    getGpuInfo: () => ipcRenderer.invoke('get-gpu-info'),
-    platform: process.platform,
-    version: require('./package.json').version
-});
-```
-
----
-
-### Task 2.1.2: Python Packaging (4-6 hours)
-
-**PyInstaller spec file (rfcp-server.spec):**
-```python
-# -*- mode: python ; coding: utf-8 -*-
-
-block_cipher = None
-
-a = Analysis(
-    ['app/main.py'],
-    pathex=[],
-    binaries=[],
-    datas=[
-        ('app', 'app'),
-    ],
-    hiddenimports=[
-        'uvicorn.logging',
-        'uvicorn.protocols.http',
-        'uvicorn.protocols.http.auto',
-        'uvicorn.protocols.websockets',
-        'uvicorn.protocols.websockets.auto',
-        'uvicorn.lifespan.on',
-        'uvicorn.lifespan.off',
-    ],
-    hookspath=[],
-    hooksconfig={},
-    runtime_hooks=[],
-    excludes=[],
-    win_no_prefer_redirects=False,
-    win_private_assemblies=False,
-    cipher=block_cipher,
-    noarchive=False,
-)
-
-pyz = PYZ(a.pure, a.zipped_data, cipher=block_cipher)
-
-exe = EXE(
-    pyz,
-    a.scripts,
-    a.binaries,
-    a.zipfiles,
-    a.datas,
-    [],
-    name='rfcp-server',
-    debug=False,
-    bootloader_ignore_signals=False,
-    strip=False,
-    upx=True,
-    upx_exclude=[],
-    runtime_tmpdir=None,
-    console=True,  # False for production
-    disable_windowed_traceback=False,
-    argv_emulation=False,
-    target_arch=None,
-    codesign_identity=None,
-    entitlements_file=None,
-    icon='../electron/build/icon.ico'
-)
-```
-
-**Build script (scripts/package-python.sh):**
-```bash
-#!/bin/bash
-set -e
-
-cd backend
-
-# Create venv for packaging
-python -m venv build_env
-source build_env/bin/activate  # or build_env\Scripts\activate on Windows
-
-# Install deps
-pip install -r requirements.txt
-pip install pyinstaller
-
-# Build
-pyinstaller rfcp-server.spec --clean
-
-# Output in dist/rfcp-server.exe
-echo "Built: dist/rfcp-server.exe"
-```
-
----
-
-### Task 2.1.3: Electron Builder Config (3-4 hours)
-
-**electron/package.json:**
-```json
-{
-  "name": "rfcp",
-  "version": "1.0.0",
-  "description": "RF Coverage Planner for Tactical Communications",
-  "main": "main.js",
-  "author": "UMTC Project",
-  "license": "MIT",
-  "scripts": {
-    "start": "electron .",
-    "build:win": "electron-builder --win",
-    "build:linux": "electron-builder --linux",
-    "build:all": "electron-builder --win --linux"
-  },
-  "devDependencies": {
-    "electron": "^28.0.0",
-    "electron-builder": "^24.9.0"
-  },
-  "build": {
-    "appId": "one.eliah.rfcp",
-    "productName": "RFCP",
-    "copyright": "Copyright © 2025 UMTC Project",
-    "directories": {
-      "output": "dist",
-      "buildResources": "build"
-    },
-    "files": [
-      "main.js",
-      "preload.js",
-      "splash.html"
-    ],
-    "extraResources": [
-      {
-        "from": "../frontend/dist",
-        "to": "frontend"
-      },
-      {
-        "from": "../backend/dist/rfcp-server",
-        "to": "backend"
-      }
-    ],
-    "win": {
-      "target": [
-        {
-          "target": "nsis",
-          "arch": ["x64"]
-        }
-      ],
-      "icon": "build/icon.ico"
-    },
-    "nsis": {
-      "oneClick": false,
-      "allowToChangeInstallationDirectory": true,
-      "installerIcon": "build/icon.ico",
-      "uninstallerIcon": "build/icon.ico",
-      "installerHeaderIcon": "build/icon.ico",
-      "createDesktopShortcut": true,
-      "createStartMenuShortcut": true,
-      "shortcutName": "RFCP"
-    },
-    "linux": {
-      "target": [
-        "AppImage",
-        "deb"
-      ],
-      "icon": "build/icon.png",
-      "category": "Science"
-    }
-  }
-}
-```
-
----
-
-### Task 2.1.4: First Run & Region Selection (4-6 hours)
-
-**First run wizard:**
-```
-┌─────────────────────────────────────────┐
-│     Welcome to RFCP                     │
-│     RF Coverage Planner                 │
-├─────────────────────────────────────────┤
-│                                         │
-│  Select your region for offline maps:   │
-│                                         │
-│  ┌─────────────────────────────────┐    │
-│  │ [x] Ukraine (~2.5 GB)           │    │
-│  │ [ ] Poland (~1.8 GB)            │    │
-│  │ [ ] Germany (~2.1 GB)           │    │
-│  │ [ ] Custom bounding box...      │    │
-│  └─────────────────────────────────┘    │
-│                                         │
-│  Data includes:                         │
-│  • Terrain elevation (SRTM 30m)         │
-│  • Building footprints (OSM)            │
-│  • Road network (OSM)                   │
-│  • Base map tiles                       │
-│                                         │
-│  [ ] Download now                       │
-│  [ ] Download later (online mode)       │
-│                                         │
-│            [Continue →]                 │
-└─────────────────────────────────────────┘
-```
-
-**Region download API endpoint:**
-```python
-@router.post("/regions/download")
-async def download_region(region: str, background_tasks: BackgroundTasks):
-    """Start region download in background"""
-    
-    REGIONS = {
-        "ukraine": {
-            "bbox": [44.0, 22.0, 52.5, 40.5],  # S, W, N, E
-            "srtm_tiles": ["N44E022", "N44E023", ...],  # ~120 tiles
-            "estimated_size": 2.5 * 1024 * 1024 * 1024  # 2.5 GB
-        },
-        # ...
-    }
-    
-    if region not in REGIONS:
-        raise HTTPException(400, "Unknown region")
-    
-    task_id = str(uuid4())
-    background_tasks.add_task(download_region_data, task_id, REGIONS[region])
-    
-    return {"task_id": task_id, "status": "started"}
-
-@router.get("/regions/progress/{task_id}")
-async def get_download_progress(task_id: str):
-    """Get download progress"""
-    return {
-        "task_id": task_id,
-        "status": "downloading",  # started, downloading, extracting, done, error
-        "progress": 45.5,  # percentage
-        "current_file": "N48E035.hgt",
-        "downloaded_mb": 1250,
-        "total_mb": 2500
-    }
-```
-
----
-
-### Task 2.1.5: Settings - GPU Configuration (2-3 hours)
-
-**Settings panel addition:**
-```typescript
-// frontend/src/components/settings/PerformanceSettings.tsx
-
-interface PerformanceSettingsProps {
-  gpuInfo: {
-    available: boolean;
-    name: string | null;
-    memory: number | null;
-  };
-}
-
-export function PerformanceSettings({ gpuInfo }: PerformanceSettingsProps) {
-  const [useGpu, setUseGpu] = useState(false);
-  const [maxWorkers, setMaxWorkers] = useState(4);
-
-  return (
-    <div className="settings-section">
-      <h3>Performance</h3>
-      
-      <div className="setting-item">
-        <label>
-          <input 
-            type="checkbox" 
-            checked={useGpu}
-            onChange={(e) => setUseGpu(e.target.checked)}
-            disabled={!gpuInfo.available}
-          />
-          Use GPU acceleration (CUDA)
-        </label>
-        {gpuInfo.available ? (
-          <span className="hint">Detected: {gpuInfo.name}</span>
-        ) : (
-          <span className="hint warning">No compatible GPU detected</span>
-        )}
-      </div>
-
-      <div className="setting-item">
-        <label>CPU Workers</label>
-        <input 
-          type="range" 
-          min="1" 
-          max="16" 
-          value={maxWorkers}
-          onChange={(e) => setMaxWorkers(Number(e.target.value))}
-        />
-        <span>{maxWorkers} threads</span>
-      </div>
-
-      <div className="setting-item">
-        <label>Default Propagation Model</label>
-        <select>
-          <option value="fast">Fast (terrain only)</option>
-          <option value="standard">Standard (+ buildings)</option>
-          <option value="detailed">Detailed (+ dominant path)</option>
-          <option value="full">Full (all models)</option>
-        </select>
-      </div>
-    </div>
-  );
-}
-```
-
-**Backend GPU detection:**
-```python
-# app/services/gpu_service.py
-
-def detect_gpu() -> dict:
-    """Detect available GPU for CUDA"""
-    result = {
-        "available": False,
-        "name": None,
-        "memory": None,
-        "cuda_version": None
-    }
-    
-    try:
-        import cupy as cp
-        device = cp.cuda.Device(0)
-        props = cp.cuda.runtime.getDeviceProperties(0)
-        
-        result["available"] = True
-        result["name"] = props["name"].decode()
-        result["memory"] = props["totalGlobalMem"] // (1024**3)  # GB
-        result["cuda_version"] = cp.cuda.runtime.runtimeGetVersion()
-    except ImportError:
-        pass  # CuPy not installed
-    except Exception as e:
-        print(f"GPU detection error: {e}")
-    
-    return result
-```
-
----
-
-### Task 2.1.6: Build & Test (3-4 hours)
-
-**Build script (scripts/build-windows.sh):**
-```bash
-#!/bin/bash
-set -e
-
-echo "=== RFCP Windows Build ==="
-
-# 1. Build frontend
-echo "Building frontend..."
-cd frontend
-npm run build
-cd ..
-
-# 2. Build backend
-echo "Building backend..."
-cd backend
-python -m venv build_env
-source build_env/Scripts/activate
-pip install -r requirements.txt
-pip install pyinstaller
-pyinstaller rfcp-server.spec --clean
-cd ..
-
-# 3. Build Electron
-echo "Building Electron app..."
-cd electron
-npm install
-npm run build:win
-cd ..
-
-echo "=== Build complete ==="
-echo "Installer: electron/dist/RFCP Setup*.exe"
-```
-
-**Test checklist:**
-```markdown
-## Install Test
-- [ ] Installer runs without admin (user install)
-- [ ] Installer runs with admin (program files)
-- [ ] Desktop shortcut created
-- [ ] Start menu entry created
-- [ ] Uninstaller works
-
-## First Run
-- [ ] Splash screen appears
-- [ ] Backend starts successfully
-- [ ] Main window loads
-- [ ] Region selection dialog shows
-- [ ] Can skip region download
-
-## Functionality
-- [ ] Map loads (online tiles)
-- [ ] Can create sites
-- [ ] Coverage calculation works
-- [ ] All presets work
-- [ ] Settings persist
-
-## Offline
-- [ ] Works without internet (after region download)
-- [ ] Offline tiles load
-- [ ] Terrain data works
-- [ ] Buildings/roads cached
-
-## Performance
-- [ ] GPU toggle appears (if GPU present)
-- [ ] GPU acceleration works
-- [ ] Memory usage reasonable (<1GB idle)
-```
-
----
-
-## 📦 Deliverables
-
-1. **RFCP-Setup-1.0.0.exe** — Windows installer (~200MB)
-2. **RFCP-1.0.0.AppImage** — Linux portable (~180MB)
-3. **RFCP-1.0.0.deb** — Debian package (~180MB)
-4. **SHA256SUMS** — Checksums file
-5. **README.md** — Installation instructions
-
----
-
-## 🔜 Future Enhancements (2.2+)
-
-- [ ] Auto-updater (electron-updater)
-- [ ] macOS support (.dmg)
-- [ ] Portable mode (no install, run from USB)
-- [ ] Silent install for deployment
-- [ ] MSI installer for enterprise
-- [ ] Code signing (Windows/macOS)
-
----
-
-## 📝 Notes
-
-- SQLite замість MongoDB для локального зберігання (простіше, не потребує сервера)
-- SRTM tiles ~25MB кожен, Україна потребує ~120 tiles = ~3GB
-- OSM дані можна завантажити з Geofabrik (ukraine-latest.osm.pbf ~1.5GB)
-- Map tiles можна кешувати з OpenStreetMap або використати MBTiles
-
----
-
-**Ready for implementation after 1.5** 🚀
diff --git a/backend/requirements.txt b/backend/requirements.txt
index fdd26f9..ec6db3d 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -9,3 +9,5 @@ numpy==1.26.4
 scipy==1.12.0
 requests==2.31.0
 httpx==0.27.0
+aiosqlite>=0.19.0
+sqlalchemy>=2.0.0
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