Prebundle mac native helpers and avoid runtime Swift compile in packaged app

.github/workflows/release.yml

@@ -44,6 +44,9 @@ jobs:
       - name: Install app dependencies
         run: npx electron-builder install-app-deps
 
+      - name: Build native macOS helpers
+        run: npm run build:native-helpers
+
       - name: Build macOS x64
         run: |
           npx tsc
@@ -77,6 +80,9 @@ jobs:
       - name: Install app dependencies
         run: npx electron-builder install-app-deps
 
+      - name: Build native macOS helpers
+        run: npm run build:native-helpers
+
       - name: Build macOS arm64
         run: |
           npx tsc

electron/ipc/handlers.ts

@@ -3,6 +3,7 @@ import { execFile, spawn, spawnSync } from 'node:child_process'
 import type { ChildProcessWithoutNullStreams } from 'node:child_process'
 
 import fs from 'node:fs/promises'
+import { constants as fsConstants } from 'node:fs'
 import { createRequire } from 'node:module'
 import path from 'node:path'
 import { promisify } from 'node:util'
@@ -202,6 +203,14 @@ function getNativeCaptureHelperSourcePath() {
   return resolveUnpackedAppPath('electron', 'native', 'ScreenCaptureKitRecorder.swift')
 }
 
+function getNativeArchTag() {
+  return process.arch === 'arm64' ? 'darwin-arm64' : 'darwin-x64'
+}
+
+function getPrebundledNativeHelperPath(binaryName: string) {
+  return resolveUnpackedAppPath('electron', 'native', 'bin', getNativeArchTag(), binaryName)
+}
+
 function getNativeCaptureHelperBinaryPath() {
   return path.join(app.getPath('userData'), 'native-tools', 'openscreen-screencapturekit-helper')
 }
@@ -247,7 +256,26 @@ type NativeMacWindowSource = {
 let cachedNativeMacWindowSources: NativeMacWindowSource[] | null = null
 let cachedNativeMacWindowSourcesAtMs = 0
 
-async function ensureSwiftHelperBinary(sourcePath: string, binaryPath: string, label: string) {
+async function ensureSwiftHelperBinary(
+  sourcePath: string,
+  binaryPath: string,
+  label: string,
+  prebundledBinaryName?: string,
+) {
+  if (prebundledBinaryName) {
+    const prebundledPath = getPrebundledNativeHelperPath(prebundledBinaryName)
+    try {
+      await fs.access(prebundledPath, fsConstants.X_OK)
+      return prebundledPath
+    } catch {
+      if (app.isPackaged) {
+        throw new Error(
+          `${label} is missing from this app build (${prebundledPath}). Reinstall or update the app.`
+        )
+      }
+    }
+  }
+
   const helperDir = path.dirname(binaryPath)
 
   await fs.mkdir(helperDir, { recursive: true })
@@ -284,7 +312,8 @@ async function ensureNativeCaptureHelperBinary() {
   return ensureSwiftHelperBinary(
     getNativeCaptureHelperSourcePath(),
     getNativeCaptureHelperBinaryPath(),
-    'native ScreenCaptureKit helper'
+    'native ScreenCaptureKit helper',
+    'openscreen-screencapturekit-helper'
   )
 }
 
@@ -292,7 +321,8 @@ async function ensureNativeWindowListBinary() {
   return ensureSwiftHelperBinary(
     getNativeWindowListSourcePath(),
     getNativeWindowListBinaryPath(),
-    'native ScreenCaptureKit window list helper'
+    'native ScreenCaptureKit window list helper',
+    'openscreen-window-list'
   )
 }
 
@@ -348,7 +378,8 @@ async function getSystemCursorAssets() {
   const binaryPath = await ensureSwiftHelperBinary(
     sourcePath,
     getSystemCursorHelperBinaryPath(),
-    'system cursor helper'
+    'system cursor helper',
+    'openscreen-system-cursors'
   )
 
   const { stdout } = await execFileAsync(binaryPath, [], { timeout: 15000, maxBuffer: 20 * 1024 * 1024 })
@@ -748,7 +779,8 @@ async function ensureNativeCursorMonitorBinary() {
   return ensureSwiftHelperBinary(
     getNativeCursorMonitorSourcePath(),
     getNativeCursorMonitorBinaryPath(),
-    'native cursor monitor helper'
+    'native cursor monitor helper',
+    'openscreen-native-cursor-monitor'
   )
 }
 

package.json

@@ -17,13 +17,14 @@
 	"scripts": {
 		"dev": "vite",
 		"postinstall": "npm run rebuild:native",
-		"build": "tsc && vite build && electron-builder",
+		"build": "npm run build:native-helpers && tsc && vite build && electron-builder",
 		"lint": "biome check .",
 		"lint:fix": "biome check --write .",
 		"format": "biome format --write .",
 		"preview": "vite preview",
 		"rebuild:native": "electron-rebuild --force --only uiohook-napi",
-		"build:mac": "tsc && vite build && electron-builder --mac",
+		"build:native-helpers": "node scripts/build-native-helpers.mjs",
+		"build:mac": "npm run build:native-helpers && tsc && vite build && electron-builder --mac",
 		"build:win": "tsc && vite build && electron-builder --win",
 		"build:linux": "tsc && vite build && electron-builder --linux",
 		"test": "vitest --run",

scripts/build-native-helpers.mjs

@@ -0,0 +1,59 @@
+import { spawnSync } from 'node:child_process';
+import { chmod, mkdir } from 'node:fs/promises';
+import path from 'node:path';
+
+const projectRoot = process.cwd();
+const nativeRoot = path.join(projectRoot, 'electron', 'native');
+
+if (process.platform !== 'darwin') {
+  console.log('[build-native-helpers] Skipping: host platform is not macOS.');
+  process.exit(0);
+}
+
+const archTag = process.arch === 'arm64' ? 'darwin-arm64' : 'darwin-x64';
+const outputDir = path.join(nativeRoot, 'bin', archTag);
+
+const helpers = [
+  {
+    source: 'ScreenCaptureKitRecorder.swift',
+    output: 'openscreen-screencapturekit-helper',
+  },
+  {
+    source: 'ScreenCaptureKitWindowList.swift',
+    output: 'openscreen-window-list',
+  },
+  {
+    source: 'SystemCursorAssets.swift',
+    output: 'openscreen-system-cursors',
+  },
+  {
+    source: 'NativeCursorMonitor.swift',
+    output: 'openscreen-native-cursor-monitor',
+  },
+];
+
+const swiftcCheck = spawnSync('swiftc', ['--version'], { encoding: 'utf8' });
+if (swiftcCheck.status !== 0) {
+  const details = [swiftcCheck.stderr, swiftcCheck.stdout].filter(Boolean).join('\n').trim();
+  throw new Error(details || 'swiftc is unavailable; install Xcode Command Line Tools.');
+}
+
+await mkdir(outputDir, { recursive: true });
+
+for (const helper of helpers) {
+  const sourcePath = path.join(nativeRoot, helper.source);
+  const outputPath = path.join(outputDir, helper.output);
+
+  const result = spawnSync('swiftc', ['-O', sourcePath, '-o', outputPath], {
+    encoding: 'utf8',
+    timeout: 120000,
+  });
+
+  if (result.status !== 0) {
+    const details = [result.stderr, result.stdout].filter(Boolean).join('\n').trim();
+    throw new Error(details || `Failed to compile ${helper.source}`);
+  }
+
+  await chmod(outputPath, 0o755);
+  console.log(`[build-native-helpers] Built ${helper.output} -> ${outputPath}`);
+}