diff --git a/action.yml b/action.yml
index d183de5..9e5e8e5 100644
--- a/action.yml
+++ b/action.yml
@@ -27,5 +27,5 @@ outputs:
   package-path:
     description: 'Path to the generated .zip package'
 runs:
-  using: 'node20'
+  using: 'node24'
   main: dist/index.js
diff --git a/src/index.js b/src/index.js
index 19f23c2..aaef377 100644
--- a/src/index.js
+++ b/src/index.js
@@ -37,28 +37,6 @@ async function execInDocker(command, args = [], opts = {}) {
     return exec.getExecOutput(command, args, opts);
 }
 
-/**
- * Run a command via exec.exec (no output capture) either on host or in Docker.
- */
-async function execRunInDocker(command, args = [], opts = {}) {
-    const dockerImage = getDockerImage();
-    if (dockerImage) {
-        const workspace = process.env.GITHUB_WORKSPACE || process.cwd();
-        const cwd = opts.cwd ? path.resolve(opts.cwd) : workspace;
-        const workDir = cwd.startsWith(workspace)
-            ? `/workspace${cwd.substring(workspace.length)}`
-            : "/workspace";
-
-        return exec.exec("docker", [
-            "run", "--rm",
-            "-v", `${workspace}:/workspace`,
-            "-w", workDir,
-            dockerImage,
-            command, ...args,
-        ]);
-    }
-    return exec.exec(command, args, opts);
-}
 
 async function determineExtensionNameFromComposerJson() {
     core.info("Detecting extension name from composer.json...");
@@ -312,13 +290,40 @@ async function extensionDetails() {
 
     return {
         releaseTag: releaseTag,
+        extName: extName,
         extSoFile: `${extName}.so`,
         extPackageName: `php_${extName}-${releaseTag}_php${phpMajorMinor}-${arch}-${os}-${libcFlavour}${zendDebug}${ztsMode}.zip`
     };
 }
 
+async function smokeTest(extName, soPath) {
+    core.info("Smoke testing extension...");
+    const phpBinary = await module.exports.determinePhpBinary();
+    const dockerImage = getDockerImage();
+
+    if (dockerImage) {
+        // Docker: fresh container may need runtime deps (libstdc++/libgcc for C++ extensions)
+        const result = await execInDocker("sh", [
+            "-c",
+            `if command -v apk >/dev/null 2>&1; then apk add --no-cache libstdc++ libgcc; fi && ${phpBinary} -d extension=${soPath} -r "echo extension_loaded('${extName}') ? 'OK' : 'FAIL';"`,
+        ]);
+        if (!result.stdout.includes("OK")) {
+            throw new Error(`Smoke test failed: extension '${extName}' did not load`);
+        }
+    } else {
+        const result = await execInDocker(phpBinary, [
+            "-d", `extension=${soPath}`,
+            "-r", `echo extension_loaded('${extName}') ? 'OK' : 'FAIL';`,
+        ]);
+        if (!result.stdout.includes("OK")) {
+            throw new Error(`Smoke test failed: extension '${extName}' did not load`);
+        }
+    }
+    core.info("Smoke test passed!");
+}
+
 async function main() {
-    const { releaseTag, extSoFile, extPackageName } = await module.exports.extensionDetails();
+    const { releaseTag, extName, extSoFile, extPackageName } = await module.exports.extensionDetails();
 
     await module.exports.buildExtension();
 
@@ -326,6 +331,9 @@ async function main() {
     const modulesDir = path.join(buildPath, "modules");
     await exec.exec("ls", ["-l", modulesDir]);
 
+    const soPath = path.join(modulesDir, extSoFile);
+    await module.exports.smokeTest(extName, soPath);
+
     await exec.exec("zip", ["-j", extPackageName, path.join(modulesDir, extSoFile)]);
 
     await module.exports.uploadReleaseAsset(releaseTag, extPackageName);
@@ -345,6 +353,7 @@ module.exports = {
     determinePhpDebugMode,
     determineZendThreadSafeMode,
     uploadReleaseAsset,
+    smokeTest,
     extensionDetails,
     main,
 };
diff --git a/tests/index.test.js b/tests/index.test.js
index f482254..f90a6dd 100644
--- a/tests/index.test.js
+++ b/tests/index.test.js
@@ -552,6 +552,7 @@ describe('extensionDetails', () => {
         expect(await action.extensionDetails())
             .toEqual({
                 releaseTag: '1.2.3',
+                extName: 'foo',
                 extSoFile: 'foo.so',
                 extPackageName: 'php_foo-1.2.3_php8.1-x86_64-linux-glibc.zip',
             });
@@ -572,6 +573,7 @@ describe('extensionDetails', () => {
         expect(await action.extensionDetails())
             .toEqual({
                 releaseTag: '1.2.3',
+                extName: 'foo',
                 extSoFile: 'foo.so',
                 extPackageName: 'php_foo-1.2.3_php8.1-x86_64-linux-glibc-debug-zts.zip',
             });
@@ -582,10 +584,12 @@ describe('main', () => {
     test('main builds and uploads extension with default build path', async () => {
         jest.spyOn(action, 'extensionDetails').mockResolvedValue({
             releaseTag: '1.2.3',
+            extName: 'foo',
             extSoFile: 'foo.so',
             extPackageName: 'php_foo-1.2.3_php8.1-x86_64-linux-glibc-debug-zts.zip',
         });
         jest.spyOn(action, 'buildExtension').mockResolvedValue();
+        jest.spyOn(action, 'smokeTest').mockResolvedValue();
         jest.spyOn(action, 'uploadReleaseAsset').mockResolvedValue();
         jest.spyOn(exec, 'exec').mockResolvedValue();
         core.getInput.mockImplementation((name) => {
@@ -605,10 +609,12 @@ describe('main', () => {
     test('main builds and uploads extension with custom build path', async () => {
         jest.spyOn(action, 'extensionDetails').mockResolvedValue({
             releaseTag: '1.2.3',
+            extName: 'foo',
             extSoFile: 'foo.so',
             extPackageName: 'php_foo-1.2.3_php8.1-x86_64-linux-glibc-debug-zts.zip',
         });
         jest.spyOn(action, 'buildExtension').mockResolvedValue();
+        jest.spyOn(action, 'smokeTest').mockResolvedValue();
         jest.spyOn(action, 'uploadReleaseAsset').mockResolvedValue();
         jest.spyOn(exec, 'exec').mockResolvedValue();
         core.getInput.mockImplementation((name) => {