diff --git a/package.json b/package.json
index efd7a11..7533f32 100644
--- a/package.json
+++ b/package.json
@@ -3,8 +3,8 @@
 	"description": "radius server for google LDAP and TTLS",
 	"version": "0.0.1",
 	"scripts": {
-		"debug": "DEBUG=radius:* ../node/node dist/app.js",
-		"start": "../node/node dist/app.js",
+		"debug": "DEBUG=radius:* node dist/app.js",
+		"start": "node dist/app.js",
 		"build": "tsc",
 		"dev": "ts-node src/app.ts",
 		"test": "mocha -r ts-node/register __tests__/**/*.test.ts",
diff --git a/src/app.ts b/src/app.ts
index 3592a73..e43888d 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -4,11 +4,20 @@ import { RadiusService } from './radius/RadiusService';
 import * as config from '../config';
 import { Authentication } from './auth';
 import { IAuthentication } from './types/Authentication';
+import { startTLSServer } from './tls/crypt';
 
 console.log(`Listener Port: ${config.port || 1812}`);
 console.log(`RADIUS Secret: ${config.secret}`);
 console.log(`Auth Mode: ${config.authentication}`);
 
+/* test node version */
+const testSocket = startTLSServer();
+if (typeof (testSocket.tls as any).exportKeyingMaterial !== 'function') {
+	console.error('UNSUPPORTED NODE VERSION FOUND!!')
+	console.log('run "sudo npx n nightly" to get nightly build of node js.');
+	process.exit(-1);
+}
+
 (async () => {
 	/* configure auth mechansim */
 	let auth: IAuthentication;