Add CI with cross-platform build matrix

.github/workflows/ci.yml

@@ -0,0 +1,37 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version-file: '.nvmrc'
+
+      - run: npm ci
+      - run: npm run build:js
+      - run: npm test
+      - run: npm run build:bundle
+      - run: npm run build:sea
+
+      - name: Smoke test the binary (Unix)
+        if: runner.os != 'Windows'
+        run: ./dist/hello CI
+
+      - name: Smoke test the binary (Windows)
+        if: runner.os == 'Windows'
+        run: .\dist\hello.exe CI

build-sea.js

@@ -16,24 +16,35 @@ try {
   execSync('node --build-sea sea-config.json', { stdio: 'inherit' });
 } catch (error) {
   console.error('\nFailed to build the SEA binary.');
-  console.error(`node --build-sea requires Node.js 24 "Krypton" LTS or newer — you are running ${process.version}.`);
-  console.error('Switch with: nvm install lts/krypton && nvm use lts/krypton');
+  console.error(`node --build-sea requires Node.js 25.5+ — you are running ${process.version}.`);
+  console.error('As of this writing it only ships on the Node 26 "Current" release line (not yet backported to the 24 LTS line). Switch with: nvm install 26 && nvm use 26');
   process.exit(1);
 }
 
-// Step 2: Sign the binary (macOS specific; required for the binary to run
+// Step 2: sea-config.json's "output" is a plain "dist/hello" with no
+// extension. On Windows that isn't directly runnable -- the file itself is
+// still a valid PE binary (it started as a copy of node.exe), so a plain
+// rename to add .exe is enough; no need to rebuild anything.
+let outputPath = 'dist/hello';
+if (process.platform === 'win32') {
+  const exePath = 'dist/hello.exe';
+  fs.renameSync(outputPath, exePath);
+  outputPath = exePath;
+}
+
+// Step 3: Sign the binary (macOS specific; required for the binary to run
 // without a Gatekeeper prompt on Apple Silicon)
 if (process.platform === 'darwin') {
   console.log('Signing the binary (macOS ad-hoc signature)...');
   try {
-    execSync('codesign --sign - dist/hello');
+    execSync(`codesign --sign - ${outputPath}`);
   } catch (error) {
     console.error('Failed to sign binary:', error.message);
     process.exit(1);
   }
 } else if (process.platform === 'win32') {
-  console.log('On Windows, sign dist/hello.exe yourself if you need a trusted binary:');
-  console.log('  signtool sign /fd SHA256 dist\\hello.exe');
+  console.log(`On Windows, sign ${outputPath} yourself if you need a trusted binary:`);
+  console.log(`  signtool sign /fd SHA256 ${outputPath}`);
 }
 
-console.log('SEA binary creation complete! The executable is ready: ./dist/hello');
+console.log(`SEA binary creation complete! The executable is ready: ./${outputPath}`);