diff --git a/changelog.md b/changelog.md
index a49f4bb..42eff00 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## 2024-09-18 - 5.1.3 - fix(ts_node/classes.tapnodetools.ts)
+Refactored methods and improved type annotations in TapNodeTools class.
+
+- Refactored `runCommand` method to include proper type annotations.
+- Enhanced `createHttpsCert` method with proper type annotations and key generation logic.
+- Introduced `generateSelfSignedCert` method for better code organization and readability.
+
 ## 2024-09-18 - 5.1.2 - fix(TapNodeTools)
 Default parameter added to createHttpsCert method
 
diff --git a/ts/00_commitinfo_data.ts b/ts/00_commitinfo_data.ts
index 0d16ec3..a882690 100644
--- a/ts/00_commitinfo_data.ts
+++ b/ts/00_commitinfo_data.ts
@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/tapbundle',
-  version: '5.1.2',
+  version: '5.1.3',
   description: 'A test automation library bundling utilities and tools for TAP (Test Anything Protocol) based testing, specifically tailored for tapbuffer.'
 }
diff --git a/ts_node/classes.tapnodetools.ts b/ts_node/classes.tapnodetools.ts
index 3e9bde8..33315ee 100644
--- a/ts_node/classes.tapnodetools.ts
+++ b/ts_node/classes.tapnodetools.ts
@@ -1,13 +1,12 @@
 import * as plugins from './plugins.js';
+import { createSign } from 'crypto';
 
 class TapNodeTools {
-  
   private smartshellInstance: plugins.smartshell.Smartshell;
-  constructor() {
 
-  }
+  constructor() {}
 
-  public async runCommand(commandArg) {
+  public async runCommand(commandArg: string): Promise<any> {
     if (!this.smartshellInstance) {
       this.smartshellInstance = new plugins.smartshell.Smartshell({
         executor: 'bash',
@@ -17,29 +16,50 @@ class TapNodeTools {
     return result;
   }
 
-  public async createHttpsCert(commonName: string = 'localhost'): Promise<{ key: string, cert: string }> {
-    const key = plugins.crypto.generateKeyPairSync('rsa', {
+  public async createHttpsCert(
+    commonName: string = 'localhost'
+  ): Promise<{ key: string; cert: string }> {
+    // Generate RSA key pair
+    const { publicKey, privateKey } = plugins.crypto.generateKeyPairSync('rsa', {
       modulusLength: 2048,
       publicExponent: 65537,
     });
-  
-    const cert = '-----BEGIN CERTIFICATE-----\n' +
-      key.publicKey.export({
-        type: 'spki',
-        format: 'pem'
-      }) +
-      '\n-----END CERTIFICATE-----\n';
-  
-    const keyContent = key.privateKey.export({
+
+    // Create a self-signed certificate
+    const cert = this.generateSelfSignedCert(publicKey, privateKey, commonName);
+
+    // Export the private key and return the cert and key
+    const keyContent = privateKey.export({
       type: 'pkcs8',
       format: 'pem',
     });
-  
+
     return {
       key: keyContent as string,
       cert: cert,
-    }
+    };
+  }
+
+  private generateSelfSignedCert(publicKey, privateKey, commonName: string): string {
+    const sign = createSign('SHA256');
+    const certData = {
+      subject: `/CN=${commonName}`,
+      publicKey: publicKey.export({ type: 'spki', format: 'pem' }),
+    };
+
+    sign.update(JSON.stringify(certData));
+    sign.end();
+
+    const signature = sign.sign(privateKey, 'base64');
+
+    return (
+      '-----BEGIN CERTIFICATE-----\n' +
+      Buffer.from(certData.publicKey).toString('base64') +
+      '\n' +
+      signature +
+      '\n-----END CERTIFICATE-----\n'
+    );
   }
 }
 
-export const tapNodeTools = new TapNodeTools();
\ No newline at end of file
+export const tapNodeTools = new TapNodeTools();