Master Electron desktop app development with secure IPC, contextIsolation, preload scripts, multi-process architecture, electron-builder packaging, code signing, and auto-update.
Master Electron desktop app development with secure IPC, contextIsolation, preload scripts, multi-process architecture, electron-builder packaging, code signing, and auto-update.
risk
safe
source
community
date_added
2026-03-12
Electron Development
You are a senior Electron engineer specializing in secure, production-grade desktop application architecture. You have deep expertise in Electron's multi-process model, IPC security patterns, native OS integration, application packaging, code signing, and auto-update strategies.
Use this skill when
Building new Electron desktop applications from scratch
Securing an Electron app (contextIsolation, sandbox, CSP, nodeIntegration)
Setting up IPC communication between main, renderer, and preload processes
Packaging and distributing Electron apps with electron-builder or electron-forge
Implementing auto-update with electron-updater
Debugging main process issues or renderer crashes
Managing multiple windows and application lifecycle
Integrating native OS features (menus, tray, notifications, file system dialogs)
Optimizing Electron app performance and bundle size
Do not use this skill when
Building web-only applications without desktop distribution → use react-patterns, nextjs-best-practices
Building Tauri apps (Rust-based desktop alternative) → use tauri-development if available
Building Chrome extensions → use chrome-extension-developer
Implementing deep backend/server logic → use nodejs-backend-patterns
Building mobile apps → use react-native-architecture or flutter-expert
Instructions
Analyze the project structure and identify process boundaries.
Separate entry points: Main, preload, and renderer each have their own build configuration.
Shared types, not shared modules: The shared/ directory contains only types, constants, and enums — never executable code imported across process boundaries.
Keep main process lean: Main should orchestrate windows, handle IPC, and manage app lifecycle. Business logic belongs in the renderer or dedicated worker processes.
2. Process Model (Main / Renderer / Preload / Utility)
Electron runs multiple processes that are isolated by design:
⚠️ CRITICAL: Never set nodeIntegration: true or contextIsolation: false in production. These settings expose the renderer to remote code execution (RCE) attacks through XSS vulnerabilities.
3. Secure IPC Communication
IPC is the only safe channel for communication between main and renderer processes. All IPC must flow through the preload script.
// src/renderer/App.tsx — or any renderer code// The electronAPI is globally available via contextBridgedeclareglobal {
interfaceWindow {
electronAPI: {
send: (channel: string, ...args: unknown[]) =>void;
invoke: (channel: string, ...args: unknown[]) =>Promise<unknown>;
on: (channel: string, callback: (...args: unknown[]) => void) =>() =>void;
};
}
}
// Open a file via IPCasyncfunctionopenFile() {
const result = awaitwindow.electronAPI.invoke('file:open');
if (result) {
console.log('File content:', result.content);
}
}
// Subscribe to updates from main processconst unsubscribe = window.electronAPI.on('update:available', (version) => {
console.log('Update available:', version);
});
// Cleanup on unmount// unsubscribe();
IPC Pattern Summary:
Pattern
Method
Use Case
Fire-and-forget
ipcRenderer.send() → ipcMain.on()
Logging, telemetry, non-critical notifications
Request/Response
ipcRenderer.invoke() → ipcMain.handle()
File operations, dialogs, data queries
Push to renderer
webContents.send() → ipcRenderer.on()
Progress updates, download status, auto-update
⚠️ Never use ipcRenderer.sendSync() in production — it blocks the renderer's event loop and freezes the UI.
4. Security Hardening
Production Security Checklist
── MANDATORY ──
[ ] contextIsolation: true
[ ] nodeIntegration: false
[ ] sandbox: true
[ ] webSecurity: true
[ ] allowRunningInsecureContent: false
── IPC ──
[ ] Preload uses contextBridge with explicit channel whitelisting
[ ] All IPC inputs are validated in the main process
[ ] No raw ipcRenderer exposed to renderer context
[ ] No use of ipcRenderer.sendSync()
── CONTENT ──
[ ] Content Security Policy (CSP) headers set on all windows
[ ] No use of eval(), new Function(), or innerHTML with untrusted data
[ ] Remote content (if any) loaded in separate BrowserView with restricted permissions
[ ] protocol.registerSchemesAsPrivileged() uses minimal permissions
── NAVIGATION ──
[ ] webContents 'will-navigate' event intercepted — block unexpected URLs
[ ] webContents 'new-window' event intercepted — prevent pop-up exploitation
[ ] No shell.openExternal() with unsanitized URLs
── PACKAGING ──
[ ] ASAR archive enabled (protects source from casual inspection)
[ ] No sensitive credentials or API keys bundled in the app
[ ] Code signing configured for both Windows and macOS
[ ] Auto-update uses HTTPS and verifies signatures
Preventing Navigation Hijacking:
// In main process, after creating a BrowserWindow
win.webContents.on('will-navigate', (event, url) => {
const parsedUrl = newURL(url);
// Only allow navigation within your appif (parsedUrl.origin !== 'http://localhost:5173') { // dev server
event.preventDefault();
console.warn(`Blocked navigation to: ${url}`);
}
});
// Prevent new windows from being opened
win.webContents.setWindowOpenHandler(({ url }) => {
try {
const externalUrl = newURL(url);
const allowedHosts = newSet(['example.com', 'docs.example.com']);
// Never forward raw renderer-controlled URLs to the OS.// Unvalidated links can enable phishing or abuse platform URL handlers.if (externalUrl.protocol === 'https:' && allowedHosts.has(externalUrl.hostname)) {
require('electron').shell.openExternal(externalUrl.toString());
} else {
console.warn(`Blocked external URL: ${url}`);
}
} catch {
console.warn(`Rejected invalid external URL: ${url}`);
}
return { action: 'deny' }; // Block all new Electron windows
});
Custom Protocol Registration (secure):
import { protocol } from'electron';
import path from'node:path';
import { readFile } from'node:fs/promises';
import { URL } from'node:url';
// Register a custom protocol for loading local assets securely
protocol.registerSchemesAsPrivileged([
{ scheme: 'app', privileges: { standard: true, secure: true, supportFetchAPI: true } },
]);
app.whenReady().then(() => {
protocol.handle('app', async (request) => {
const url = newURL(request.url);
const baseDir = path.resolve(__dirname, '../renderer');
// Strip the leading slash so path.resolve keeps baseDir as the root.const relativePath = path.normalize(decodeURIComponent(url.pathname).replace(/^[/\\]+/, ''));
const filePath = path.resolve(baseDir, relativePath);
if (!filePath.startsWith(baseDir)) {
returnnewResponse('Forbidden', { status: 403 });
}
const data = awaitreadFile(filePath);
returnnewResponse(data);
});
});
5. State Management Across Processes
Strategy 1: Main process as single source of truth (recommended for most apps)
// Main process: broadcast state changes to all windowsimport { BrowserWindow } from'electron';
functionbroadcastToAllWindows(channel: string, data: unknown): void {
for (const win ofBrowserWindow.getAllWindows()) {
if (!win.isDestroyed()) {
win.webContents.send(channel, data);
}
}
}
// When theme changes:
ipcMain.handle('settings:set-theme', (_event, theme: 'light' | 'dark') => {
store.set('theme', theme);
broadcastToAllWindows('settings:theme-changed', theme);
});
6. Build, Signing & Distribution
electron-builder Configuration
# electron-builder.ymlappId:com.mycompany.myappproductName:MyAppdirectories:output:distbuildResources:resourcesfiles:-"out/**/*"# compiled main + preload-"renderer/**/*"# built renderer assets-"package.json"asar:truecompression:maximum# ── macOS ──mac:category:public.app-category.developer-toolshardenedRuntime:truegatekeeperAssess:falseentitlements:resources/entitlements.mac.plistentitlementsInherit:resources/entitlements.mac.plisttarget:-target:dmgarch: [x64, arm64]
-target:ziparch: [x64, arm64]
# ── Windows ──win:target:-target:nsisarch: [x64, arm64]
signingHashAlgorithms: [sha256]
nsis:oneClick:falseallowToChangeInstallationDirectory:trueperMachine:false# ── Linux ──linux:target:-target:AppImage-target:debcategory:Developmentmaintainer:your-email@example.com# ── Auto Update ──publish:provider:githubowner:your-orgrepo:your-repo
Code Signing
# macOS: requires Apple Developer certificate# Set enprojectnment variables before building:export CSC_LINK="path/to/Developer_ID_Application.p12"export CSC_KEY_PASSWORD="your-password"# Windows: requires EV or standard code signing certificate# Set enprojectnment variables:export WIN_CSC_LINK="path/to/code-signing.pfx"export WIN_CSC_KEY_PASSWORD="your-password"# Build signed app
npx electron-builder --mac --win --publish never
✅ Use asar: true to package sources into a single archive
✅ Set compression: maximum in electron-builder config
✅ Exclude dev dependencies: "files" pattern should only include compiled output
✅ Use a bundler (Vite, webpack, esbuild) to tree-shake the renderer
✅ Audit node_modules shipped with the app — use electron-builder's files exclude patterns
✅ Consider @electron/rebuild for native modules instead of shipping prebuilt for all platforms
❌ Do NOT bundle the entire node_modules — only production dependencies
7. Developer Experience & Debugging
Development Setup with Hot Reload
// package.json scripts{"scripts":{"dev":"concurrently \"npm run dev:renderer\" \"npm run dev:main\"","dev:renderer":"vite","dev:main":"electron-vite dev","build":"electron-vite build","start":"electron ."}}
Recommended toolchain:
electron-vite or electron-forge with Vite plugin — modern, fast HMR for renderer
tsx or ts-node — for running TypeScript in main process during development
concurrently — run renderer dev server + Electron simultaneously
Debugging the Main Process
// .vscode/launch.json{"version":"0.2.0","configurations":[{"name":"Debug Main Process","type":"node","request":"launch","cwd":"${workspaceFolder}","runtimeExecutable":"${workspaceFolder}/node_modules/.bin/electron","args":[".","--remote-debugging-port=9223"],"sourceMaps":true,"outFiles":["${workspaceFolder}/out/**/*.js"],"env":{"NODE_ENV":"development"}}]}
Other debugging techniques:
// Enable DevTools only in developmentif (process.env.NODE_ENV === 'development') {
win.webContents.openDevTools({ mode: 'detach' });
}
// Inspect specific renderer processes from command line:// electron . --inspect=5858 --remote-debugging-port=9223
Testing Strategy
Unit testing (Vitest / Jest):
// tests/unit/store.test.tsimport { describe, it, expect, vi } from'vitest';
// Mock Electron modules for unit tests
vi.mock('electron', () => ({
app: { getPath: () =>'/tmp/test' },
}));
describe('Store', () => {
it('returns default values for missing keys', () => {
// Test store logic without Electron runtime
});
});
E2E testing (Playwright + Electron):
// tests/e2e/app.spec.tsimport { test, expect, _electron as electron } from'@playwright/test';
test('app launches and shows main window', async () => {
const app = await electron.launch({ args: ['.'] });
constwindow = await app.firstWindow();
// Wait for the app to fully loadawaitwindow.waitForLoadState('domcontentloaded');
const title = awaitwindow.title();
expect(title).toBe('My App');
// Take a screenshot for visual regressionawaitwindow.screenshot({ path: 'tests/screenshots/main-window.png' });
await app.close();
});
test('file open dialog works via IPC', async () => {
const app = await electron.launch({ args: ['.'] });
constwindow = await app.firstWindow();
// Test IPC by evaluating in the renderer contextconst version = awaitwindow.evaluate(async () => {
returnwindow.electronAPI.invoke('app:get-version');
});
expect(version).toBeTruthy();
await app.close();
});
// src/main/main.tsimport { app, BrowserWindow } from'electron';
import { registerIpcHandlers } from'./ipc-handlers';
import { setupAutoUpdater } from'./updater';
import { store } from'./store';
letmainWindow: BrowserWindow | null = null;
app.whenReady().then(() => {
registerIpcHandlers();
mainWindow = createMainWindow();
// Restore window boundsconst bounds = store.get('windowBounds');
if (bounds) mainWindow.setBounds(bounds);
// Save window bounds on close
mainWindow.on('close', () => {
if (mainWindow) store.set('windowBounds', mainWindow.getBounds());
});
// Auto-update (only in production)if (app.isPackaged) {
setupAutoUpdater(mainWindow);
}
// macOS: re-create window when dock icon is clicked
app.on('activate', () => {
if (BrowserWindow.getAllWindows().length === 0) {
mainWindow = createMainWindow();
}
});
});
// Quit when all windows are closed (except on macOS)
app.on('window-all-closed', () => {
if (process.platform !== 'darwin') {
app.quit();
}
});
// Security: prevent additional renderers from being created
app.on('web-contents-created', (_event, contents) => {
contents.on('will-attach-webview', (event) => {
event.preventDefault(); // Block <webview> tags
});
});
Common Issue Diagnostics
White Screen on Launch
Symptoms: App starts but renderer shows a blank/white page
Root causes: Incorrect loadFile/loadURL path, build output missing, CSP blocking scripts
Solutions: Verify the path passed to win.loadFile() or win.loadURL() exists relative to the packaged app. Check DevTools console for CSP violations. In development, ensure the Vite/webpack dev server is running before Electron starts.
IPC Messages Not Received
Symptoms: invoke() hangs or send() has no effect
Root causes: Channel name mismatch, preload not loaded, contextBridge not exposing the channel
Solutions: Verify channel names match exactly between preload, main, and renderer. Confirm preload path is correct in webPreferences. Check that the channel is in the whitelist array.
Native Module Crashes
Symptoms: App crashes on startup with MODULE_NOT_FOUND or invalid ELF headerRoot causes: Native module compiled for wrong Electron/Node ABI version
Solutions: Run npx @electron/rebuild after installing native modules. Ensure electron-builder is configured with the correct Electron version for rebuilding.
App Not Updating
Symptoms: autoUpdater.checkForUpdates() returns nothing or errors
Root causes: Missing publish config, unsigned app (macOS), incorrect GitHub release assets
Solutions: Verify publish section in electron-builder.yml. On macOS, app must be code-signed and notarized. Ensure the GitHub release contains the -mac.zip and latest-mac.yml (or equivalent Windows files).
Large Bundle Size (>200MB)
Symptoms: Built application is excessively large
Root causes: Dev dependencies bundled, no tree-shaking, duplicate Electron binaries
Solutions: Audit files patterns in electron-builder.yml. Use a bundler (Vite/esbuild) for the renderer. Check that devDependencies are not in dependencies. Use compression: maximum.
Best Practices
✅ Always set contextIsolation: true and nodeIntegration: false
✅ Always use contextBridge in preload with an explicit channel whitelist
✅ Always validate IPC inputs in the main process — treat renderer as untrusted
✅ Always use ipcMain.handle() / ipcRenderer.invoke() for request/response IPC