Unexpected identifier on async Error on Azure DevOps Custom pipelines task

if you have followed Microsoft’s “Add a custom pipelines task extension” it does a great Job on giving you the basics of how you can create a new NodeJS custom pipelines task, and it gives a very good starting point for your custom pipelines task. it even comes with mocha tests with, “azure-pipelines-task-lib/mock-test” which help you to mock how task will run as a task.

if you are using any library which their js files uses async await, or some of the new Node capabilities you may get

async {merthod name}(request) { 
^^^^^^^^^^^^^^^^ 
SyntaxError: Unexpected identifier

if you have this problem
task.json file:

{
 "$schema": "https://raw.githubusercontent.com/Microsoft/azure-pipelines-task-lib/master/tasks.schema.json",
 "id": "{{taskguid}}",
 "name": "{{taskname}}",
 "friendlyName": "{{taskfriendlyname}}",
 "description": "{{taskdescription}}",
 "helpMarkDown": "",
 "category": "Utility",
 "author": "{{taskauthor}}",
 "version": {
     "Major": 0,
     "Minor": 1,
     "Patch": 0
 },
 "instanceNameFormat": "Echo $(samplestring)",
 "inputs": [
     {
         "name": "samplestring",
         "type": "string",
         "label": "Sample String",
         "defaultValue": "",
         "required": true,
         "helpMarkDown": "A sample string"
     }
 ],
 "execution": {
     "Node": {
         "target": "index.js"
     }
 }
 }

Update execution.Node to Node10 or Node16 in task.json like

  "execution": {
    "Node10": {
      "target": "index.js",
      "argumentFormat": ""
    },
    "Node16": {
      ""target": "index.js",
      "argumentFormat": ""
    }

This will allow you to use Node10 or Node16 Functionalities in your task