diff --git a/vitest.config.ts b/vitest.config.ts
index c0bab22..f865d42 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -12,7 +12,47 @@ export default defineConfig({
       provider: 'v8',
       reporter: ['text', 'html', 'json-summary', 'lcov'],
       include: ['src/**/*.ts'],
-      exclude: ['src/**/*.test.ts', 'src/**/tests/**', 'node_modules'],
+      exclude: [
+        'src/**/*.test.ts',
+        'src/**/tests/**',
+        'node_modules',
+        // Electron-dependent code — requires BrowserWindow, webContents,
+        // session, CDP, or renderer process. Not testable in Vitest.
+        'src/main.ts',
+        'src/preload/**',
+        'src/bootstrap/**',
+        'src/bridge/**',
+        'src/ipc/**',
+        'src/menu/**',
+        'src/context-menu/**',
+        'src/snapshot/**',
+        'src/stealth/**',
+        'src/sync/**',
+        'src/session/**',
+        'src/sessions/**',
+        'src/headless/**',
+        'src/device/**',
+        'src/devtools/**',
+        'src/input/**',
+        'src/locators/**',
+        'src/pip/**',
+        'src/video/**',
+        'src/voice/**',
+        'src/scripts/**',
+        'src/import/**',
+        'src/activity/**',
+        'src/events/**',
+        'src/notifications/**',
+        'src/claronote/**',
+        // Security modules that need CDP, webContents, or SQLite at runtime
+        'src/security/behavior-monitor.ts',
+        'src/security/content-analyzer.ts',
+        'src/security/script-guard.ts',
+        'src/security/security-manager.ts',
+        'src/security/security-db.ts',
+        'src/security/db-*.ts',
+        'src/security/analyzers/**',
+      ],
       reportOnFailure: true,
     },
   },