VsCode launch task after Parcel

[jonlepage]

Hey guys, how i can launch Parcel than launch another script after server launch?
Am trying here to make a tasks launcher with my scripts Parcel before and after launch my script for nwjs+ debugger , but not succeed.

Anybody have some suggestion code to share for try the best approach ?

This is my script in package.json

  "scripts": {
    "postinstall": "cd ./node_modules/nw  &&  npm install --nwjs_build_type=sdk",

    "start": "node scripts/copy.js && parcel src/index.html ",
    "start-nw": "nw dist/ --remote-debugging-port=9229",

    "build": "parcel build src/index.html --out-dir build",
    "build-nwjs": "nwbuild --platforms win64,osx64,linux64 --buildDir ./build dist"
  },

this is my launch.json for now

{
  "version": "0.2.0",
  "configurations": [
    {
      "name": "Launch Parcel",
      "command": "npm start",
      "request": "launch",
      "type": "node-terminal"
    },
    {
      "name": "Launch NWjs",
      "type": "nwjs",
      "request": "launch",
      "runtimeExecutable": "${workspaceRoot}\\node_modules\\nw\\nwjs\\nw.exe",
      "webRoot": "${workspaceRoot}/dist",
      "port": 9222,
      "reloadAfterAttached": true
    }
  ],
  "compounds": [
    {
      "name": "Full-Dev",
      "configurations": ["Launch Parcel", "Launch NWjs"]
    }
  ]
}

i can execute with success in terminal
npm start
then when is ready
npm run start-nw
then F12 to attach vscode to nwjs app
HotReload also work fine here !

But i want be able to run this with only one key (f12) to run Parcel , nwjs, than attache to Vscode !?

Anybody have similar example, Nwjs or Elelectron.
The issue is if i use "preLaunchTask": "npm: start" the process never end, because parcel start a server and never tell "hey am ready" to process.
I think i need a great example to understand.
ps: sorry for poor English :)